[ { "sku": "QJ-213-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 213 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 65, "D_mm": 120, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 110, "static_load_kN": 112, "fatigue_load_limit_kN": 4.75, "limiting_speed_rpm": 9500, "max_rpm": 9500, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 213 N2MA is SKF's 65 mm-bore QJ four-point contact ball bearing of the QJ200 series, 65×120×23 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 65×120×23 mm (2.559×4.724×0.906 in), 27.5 mm radial section height, C 110 kN, C0 112 kN, Pu 4.75 kN.SKF publishes only the 9,500 r/min limiting speed for this execution, catalogue mass 1200 g. Load balance: C0 112 kN against C 110 kN gives a 1.02 ratio, typical of a four-point thrust-oriented design; Pu 4.75 kN enters the SKF adjusted-life equation rather than the basic rating life. Speed planning distinguishes the two published ceilings mechanically: the cage and balls tolerate 9,500 r/min and no separate thermal reference is published; at dm ≈ 92.5 mm the corresponding dn is approximately 879k mm·r/min. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 9,500 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "heavy gearbox locating positions", "screw conveyor and extruder thrust positions", "crane travel and hoist drives" ], "failure_modes": [ "cage wear from speed above the limiting value with thin or aged lubricant", "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "electrical pitting on VFD-driven shafts without grounding protection", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Run the QJ as a thrust bearing with radial clearance in the housing, paired with a separate radial bearing; the QJ outer ring must not be radially clamped.", "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "Anti-rotation is built into QJ-213-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-213-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 213 N2MA as the qj slotted execution; the other order numbers of the QJ 213 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-213-N2MA?", "a": "QJ 213 N2MA measures 65 mm bore × 120 mm OD × 23 mm width (2.559 × 4.724 × 0.906 in), mass about 1200 g. SKF 17000 ratings: C 110 kN, C0 112 kN, Pu 4.75 kN, SKF publishes only the 9,500 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." }, { "q": "What minimum axial load does QJ-213-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." } ], "cross_ref": [ { "equiv_sku": "7213-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×120×23 mm envelope, but catalogue C/C0 differ between executions (110/112 kN vs 66.3/54 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7213-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×120×23 mm envelope, but catalogue C/C0 differ between executions (110/112 kN vs 69.5/57 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7213-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×120×23 mm envelope, but catalogue C/C0 differ between executions (110/112 kN vs 69.5/57 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7213-BEGAPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×120×23 mm envelope, but catalogue C/C0 differ between executions (110/112 kN vs 69.5/57 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7213-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×120×23 mm envelope, but catalogue C/C0 differ between executions (110/112 kN vs 69.5/57 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7213-ACCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×120×23 mm envelope, but catalogue C/C0 differ between executions (110/112 kN vs 81.5/65.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-213-N2PHAS", "equiv_brand": "SKF", "level": "full", "note": "Same 65×120×23 mm envelope with catalogue ratings within 10 %; QJ 213 N2PHAS is the PEEK cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "QJ-213-MA", "equiv_brand": "SKF", "level": "full", "note": "Same 65×120×23 mm envelope with catalogue ratings within 10 %; QJ 213 MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7213", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7213 BEP shares the 65×120×23 mm angular-contact envelope, but catalogue C/C0 differ (110/112 kN vs 66.3/54 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-213-N2MA", "QJ 213 N2MA" ], "locale_variants": {} }, { "sku": "QJ-213-MA", "brand": "SKF", "manufacturer_designation": "QJ 213 MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 65, "D_mm": 120, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 110, "static_load_kN": 112, "fatigue_load_limit_kN": 4.75, "limiting_speed_rpm": 9500, "max_rpm": 9500, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 213 MA is SKF's 65 mm-bore QJ four-point contact ball bearing of the QJ200 series, 65×120×23 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 65×120×23 mm (2.559×4.724×0.906 in), 27.5 mm radial section height, C 110 kN, C0 112 kN, Pu 4.75 kN.SKF publishes only the 9,500 r/min limiting speed for this execution, catalogue mass 1200 g. At the printed limiting speed of 9,500 r/min the mean pitch diameter dm ≈ 92.5 mm implies a dn value around 879k mm·r/min; only the limiting speed is published for this execution. The 4.75 kN fatigue load limit is the equivalent-load floor for long-life adjustment; with 110/112 kN ratings and 1200 g mass this execution carries about 1.69 kN of C per millimetre of bore. Bore-to-OD planning: OD 120 over bore 65 is a 1.85× step for this size, and the 23 mm width gives a bore/width ratio of 2.83; use these ratios when housing space around the 65 mm shaft is the first constraint. Plain outer-ring execution: this order number is delivered without N2 locating slots, so anti-rotation is solved in the housing instead — a shoulder dog, a spring-loaded key, a cover feature or an interference-free circlip arrangement. Because the outer ring deliberately runs with radial clearance and a small axial float gap, omitting positive anti-rotation invites seat fretting; the slotted N2 order number is the alternative when the housing can provide engagement pins.", "applications": [ "crane travel and hoist drives", "turret and slewing drives", "paper-machine calender stacks" ], "failure_modes": [ "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "outer-ring creep and seat fretting where a N2-locating-slot bearing is not positively stopped", "outer-ring creep and seat fretting because the plain ring has no N2 slots and relies on housing-provided anti-rotation", "edge loading from shaft deflection or housing misalignment", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "Anti-rotation is NOT built into QJ-213-MA: without N2 slots the housing must provide a dog, keyed cover or other positive stop, since the outer ring runs radially loose by design.", "The MA brass cage of QJ-213-MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 213 MA as the qj plain execution; the other order numbers of the QJ 213 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-213-MA?", "a": "QJ 213 MA measures 65 mm bore × 120 mm OD × 23 mm width (2.559 × 4.724 × 0.906 in), mass about 1200 g. SKF 17000 ratings: C 110 kN, C0 112 kN, Pu 4.75 kN, SKF publishes only the 9,500 r/min limiting speed for this execution." }, { "q": "What does the MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What minimum axial load does QJ-213-MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." } ], "cross_ref": [ { "equiv_sku": "7213-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×120×23 mm envelope, but catalogue C/C0 differ between executions (110/112 kN vs 66.3/54 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7213-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×120×23 mm envelope, but catalogue C/C0 differ between executions (110/112 kN vs 69.5/57 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7213-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×120×23 mm envelope, but catalogue C/C0 differ between executions (110/112 kN vs 69.5/57 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7213-BEGAPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×120×23 mm envelope, but catalogue C/C0 differ between executions (110/112 kN vs 69.5/57 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7213-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×120×23 mm envelope, but catalogue C/C0 differ between executions (110/112 kN vs 69.5/57 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7213-ACCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×120×23 mm envelope, but catalogue C/C0 differ between executions (110/112 kN vs 81.5/65.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-213-N2PHAS", "equiv_brand": "SKF", "level": "full", "note": "Same 65×120×23 mm envelope with catalogue ratings within 10 %; QJ 213 N2PHAS is the PEEK cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "QJ-213-N2MA", "equiv_brand": "SKF", "level": "full", "note": "Same 65×120×23 mm envelope with catalogue ratings within 10 %; QJ 213 N2MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7213", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7213 BEP shares the 65×120×23 mm angular-contact envelope, but catalogue C/C0 differ (110/112 kN vs 66.3/54 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-213-MA", "QJ 213 MA" ], "locale_variants": {} }, { "sku": "QJ-313-N2PHAS", "brand": "SKF", "manufacturer_designation": "QJ 313 N2PHAS", "series": "QJ300-series", "type": "angular_contact", "d_mm": 65, "D_mm": 140, "B_mm": 33, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer", "dynamic_load_kN": 176, "static_load_kN": 156, "fatigue_load_limit_kN": 6.55, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 2700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 313 N2PHAS is SKF's 65 mm-bore QJ four-point contact ball bearing of the QJ300 series, 65×140×33 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. glass-fibre reinforced PEEK cage, outer-ring-centred with lubrication grooves in the guiding surfaces (suffix PHAS), for very high-speed oil-air or grease lubrication. Envelope 65×140×33 mm (2.559×5.512×1.299 in), 37.5 mm radial section height, C 176 kN, C0 156 kN, Pu 6.55 kN.SKF publishes only the 8,500 r/min limiting speed for this execution, catalogue mass 2700 g. At the printed limiting speed of 8,500 r/min the mean pitch diameter dm ≈ 102.5 mm implies a dn value around 871k mm·r/min; only the limiting speed is published for this execution. The 6.55 kN fatigue load limit is the equivalent-load floor for long-life adjustment; with 176/156 kN ratings and 2700 g mass this execution carries about 2.71 kN of C per millimetre of bore. Bore-to-OD planning: OD 140 over bore 65 is a 2.15× step for this size, and the 33 mm width gives a bore/width ratio of 1.97; use these ratios when housing space around the 65 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "crane travel and hoist drives", "turret and slewing drives", "paper-machine calender stacks" ], "failure_modes": [ "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "outer-ring creep and seat fretting where a N2-locating-slot bearing is not positively stopped", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "edge loading from shaft deflection or housing misalignment", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "Anti-rotation is built into QJ-313-N2PHAS: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The PHAS PEEK cage of QJ-313-N2PHAS is outer-ring-centred with lubrication grooves: feed clean oil-air or appropriate grease to the guide land and inspect groove filling at overhaul.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 313 N2PHAS as the qj slotted execution; the other order numbers of the QJ 313 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-313-N2PHAS?", "a": "QJ 313 N2PHAS measures 65 mm bore × 140 mm OD × 33 mm width (2.559 × 5.512 × 1.299 in), mass about 2700 g. SKF 17000 ratings: C 176 kN, C0 156 kN, Pu 6.55 kN, SKF publishes only the 8,500 r/min limiting speed for this execution." }, { "q": "What does the N2PHAS suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. glass-fibre reinforced PEEK cage, outer-ring-centred with lubrication grooves in the guiding surfaces (suffix PHAS), for very high-speed oil-air or grease lubrication." }, { "q": "What minimum axial load does QJ-313-N2PHAS require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." } ], "cross_ref": [ { "equiv_sku": "7313-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×140×33 mm envelope, but catalogue C/C0 differ between executions (176/156 kN vs 108/80 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7313-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×140×33 mm envelope, but catalogue C/C0 differ between executions (176/156 kN vs 116/86.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7313-BECBPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×140×33 mm envelope, but catalogue C/C0 differ between executions (176/156 kN vs 116/86.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7313-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×140×33 mm envelope, but catalogue C/C0 differ between executions (176/156 kN vs 116/86.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7313-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×140×33 mm envelope, but catalogue C/C0 differ between executions (176/156 kN vs 116/86.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7313-ACCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×140×33 mm envelope, but catalogue C/C0 differ between executions (176/156 kN vs 132/96.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-313-MA", "equiv_brand": "SKF", "level": "full", "note": "Same 65×140×33 mm envelope with catalogue ratings within 10 %; QJ 313 MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7313", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7313 BEP shares the 65×140×33 mm angular-contact envelope, but catalogue C/C0 differ (176/156 kN vs 108/80 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-313-N2PHAS", "QJ 313 N2PHAS" ], "locale_variants": {} }, { "sku": "QJ-313-MA", "brand": "SKF", "manufacturer_designation": "QJ 313 MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 65, "D_mm": 140, "B_mm": 33, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 176, "static_load_kN": 156, "fatigue_load_limit_kN": 6.55, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 2700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 313 MA is SKF's 65 mm-bore QJ four-point contact ball bearing of the QJ300 series, 65×140×33 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 65×140×33 mm (2.559×5.512×1.299 in), 37.5 mm radial section height, C 176 kN, C0 156 kN, Pu 6.55 kN.SKF publishes only the 8,500 r/min limiting speed for this execution, catalogue mass 2700 g. The 6.55 kN fatigue load limit is the equivalent-load floor for long-life adjustment; with 176/156 kN ratings and 2700 g mass this execution carries about 2.71 kN of C per millimetre of bore. Sizing arithmetic on the 65 mm bore: 176 kN C divided by the 37.5 mm radial section height gives 4.7 kN per section millimetre; the 2700 g mass and 4 % Pu/C share frame the light-load floor for the adjusted-life check. Bore-to-OD planning: OD 140 over bore 65 is a 2.15× step for this size, and the 33 mm width gives a bore/width ratio of 1.97; use these ratios when housing space around the 65 mm shaft is the first constraint. Plain outer-ring execution: this order number is delivered without N2 locating slots, so anti-rotation is solved in the housing instead — a shoulder dog, a spring-loaded key, a cover feature or an interference-free circlip arrangement. Because the outer ring deliberately runs with radial clearance and a small axial float gap, omitting positive anti-rotation invites seat fretting; the slotted N2 order number is the alternative when the housing can provide engagement pins.", "applications": [ "crane travel and hoist drives", "turret and slewing drives", "paper-machine calender stacks" ], "failure_modes": [ "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "false brinelling while the shaft stands with pure radial load and no minimum axial load", "outer-ring creep and seat fretting because the plain ring has no N2 slots and relies on housing-provided anti-rotation", "raceway staining from water in the lubricant during idle periods", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Run the QJ as a thrust bearing with radial clearance in the housing, paired with a separate radial bearing; the QJ outer ring must not be radially clamped.", "Without N2 slots, provide another positive anti-rotation feature for the radially loose outer ring", "Run the QJ as a thrust bearing with radial clearance in the housing, paired with a separate radial bearing; the QJ outer ring must not be radially clamped.", "Anti-rotation is NOT built into QJ-313-MA: without N2 slots the housing must provide a dog, keyed cover or other positive stop, since the outer ring runs radially loose by design.", "The MA brass cage of QJ-313-MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 313 MA as the qj plain execution; the other order numbers of the QJ 313 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-313-MA?", "a": "QJ 313 MA measures 65 mm bore × 140 mm OD × 33 mm width (2.559 × 5.512 × 1.299 in), mass about 2700 g. SKF 17000 ratings: C 176 kN, C0 156 kN, Pu 6.55 kN, SKF publishes only the 8,500 r/min limiting speed for this execution." }, { "q": "What does the MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." }, { "q": "What does QJ mean in QJ 313 MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." } ], "cross_ref": [ { "equiv_sku": "7313-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×140×33 mm envelope, but catalogue C/C0 differ between executions (176/156 kN vs 108/80 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7313-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×140×33 mm envelope, but catalogue C/C0 differ between executions (176/156 kN vs 116/86.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7313-BECBPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×140×33 mm envelope, but catalogue C/C0 differ between executions (176/156 kN vs 116/86.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7313-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×140×33 mm envelope, but catalogue C/C0 differ between executions (176/156 kN vs 116/86.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7313-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×140×33 mm envelope, but catalogue C/C0 differ between executions (176/156 kN vs 116/86.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7313-ACCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×140×33 mm envelope, but catalogue C/C0 differ between executions (176/156 kN vs 132/96.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-313-N2PHAS", "equiv_brand": "SKF", "level": "full", "note": "Same 65×140×33 mm envelope with catalogue ratings within 10 %; QJ 313 N2PHAS is the PEEK cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7313", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7313 BEP shares the 65×140×33 mm angular-contact envelope, but catalogue C/C0 differ (176/156 kN vs 108/80 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-313-MA", "QJ 313 MA" ], "locale_variants": {} }, { "sku": "QJ-214-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 214 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 70, "D_mm": 125, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 120, "static_load_kN": 122, "fatigue_load_limit_kN": 5.2, "limiting_speed_rpm": 9000, "max_rpm": 9000, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 214 N2MA is SKF's 70 mm-bore QJ four-point contact ball bearing of the QJ200 series, 70×125×24 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 70×125×24 mm (2.756×4.921×0.945 in), 27.5 mm radial section height, C 120 kN, C0 122 kN, Pu 5.2 kN.SKF publishes only the 9,000 r/min limiting speed for this execution, catalogue mass 1300 g. Speed planning distinguishes the two published ceilings mechanically: the cage and balls tolerate 9,000 r/min and no separate thermal reference is published; at dm ≈ 97.5 mm the corresponding dn is approximately 878k mm·r/min. At the printed limiting speed of 9,000 r/min the mean pitch diameter dm ≈ 97.5 mm implies a dn value around 878k mm·r/min; only the limiting speed is published for this execution. Bore-to-OD planning: OD 125 over bore 70 is a 1.79× step for this size, and the 24 mm width gives a bore/width ratio of 2.92; use these ratios when housing space around the 70 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "paper-machine calender stacks", "heavy gearbox locating positions", "screw conveyor and extruder thrust positions" ], "failure_modes": [ "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "outer-ring creep and seat fretting where a N2-locating-slot bearing is not positively stopped", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "mounting score marks when the bearing is cocked over a burr or keyway", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "Anti-rotation is built into QJ-214-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-214-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 214 N2MA as the qj slotted execution; the other order numbers of the QJ 214 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-214-N2MA?", "a": "QJ 214 N2MA measures 70 mm bore × 125 mm OD × 24 mm width (2.756 × 4.921 × 0.945 in), mass about 1300 g. SKF 17000 ratings: C 120 kN, C0 122 kN, Pu 5.2 kN, SKF publishes only the 9,000 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What minimum axial load does QJ-214-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." } ], "cross_ref": [ { "equiv_sku": "7214-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 67.6/56 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7214-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 72/60 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7214-BECBPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 72/60 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7214-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 72/60 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7214-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 75/64 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7214-ACCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 83/68 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-214-MA", "equiv_brand": "SKF", "level": "full", "note": "Same 70×125×24 mm envelope with catalogue ratings within 10 %; QJ 214 MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "QJ-214-N2PHAS", "equiv_brand": "SKF", "level": "full", "note": "Same 70×125×24 mm envelope with catalogue ratings within 10 %; QJ 214 N2PHAS is the PEEK cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7214", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7214 BEP shares the 70×125×24 mm angular-contact envelope, but catalogue C/C0 differ (120/122 kN vs 67.6/56 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-214-N2MA", "QJ 214 N2MA" ], "locale_variants": {} }, { "sku": "QJ-214-MA", "brand": "SKF", "manufacturer_designation": "QJ 214 MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 70, "D_mm": 125, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 120, "static_load_kN": 122, "fatigue_load_limit_kN": 5.2, "limiting_speed_rpm": 9000, "max_rpm": 9000, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 214 MA is SKF's 70 mm-bore QJ four-point contact ball bearing of the QJ200 series, 70×125×24 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 70×125×24 mm (2.756×4.921×0.945 in), 27.5 mm radial section height, C 120 kN, C0 122 kN, Pu 5.2 kN.SKF publishes only the 9,000 r/min limiting speed for this execution, catalogue mass 1300 g. Load balance: C0 122 kN against C 120 kN gives a 1.02 ratio, typical of a four-point thrust-oriented design; Pu 5.2 kN enters the SKF adjusted-life equation rather than the basic rating life. Mass and section check: 1300 g inside the 70×125×24 mm outline leaves a 27.5 mm radial section, and the 122 kN static rating is 1.02× the dynamic rating — plan static safety and minimum load against those numbers rather than against sister executions. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 9,000 r/min limiting value is the single published ceiling. Plain outer-ring execution: this order number is delivered without N2 locating slots, so anti-rotation is solved in the housing instead — a shoulder dog, a spring-loaded key, a cover feature or an interference-free circlip arrangement. Because the outer ring deliberately runs with radial clearance and a small axial float gap, omitting positive anti-rotation invites seat fretting; the slotted N2 order number is the alternative when the housing can provide engagement pins.", "applications": [ "paper-machine calender stacks", "heavy gearbox locating positions", "screw conveyor and extruder thrust positions" ], "failure_modes": [ "outer-ring creep and seat fretting where a N2-locating-slot bearing is not positively stopped", "axial over-travel when the outer ring is clamped instead of left with radial clearance and a small end-play gap", "outer-ring creep and seat fretting because the plain ring has no N2 slots and relies on housing-provided anti-rotation", "electrical pitting on VFD-driven shafts without grounding protection", "raceway staining from water in the lubricant during idle periods" ], "pitfalls": [ "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Without N2 slots, provide another positive anti-rotation feature for the radially loose outer ring", "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Anti-rotation is NOT built into QJ-214-MA: without N2 slots the housing must provide a dog, keyed cover or other positive stop, since the outer ring runs radially loose by design.", "The MA brass cage of QJ-214-MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 214 MA as the qj plain execution; the other order numbers of the QJ 214 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-214-MA?", "a": "QJ 214 MA measures 70 mm bore × 125 mm OD × 24 mm width (2.756 × 4.921 × 0.945 in), mass about 1300 g. SKF 17000 ratings: C 120 kN, C0 122 kN, Pu 5.2 kN, SKF publishes only the 9,000 r/min limiting speed for this execution." }, { "q": "What does the MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." }, { "q": "What minimum axial load does QJ-214-MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." } ], "cross_ref": [ { "equiv_sku": "7214-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 67.6/56 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7214-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 72/60 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7214-BECBPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 72/60 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7214-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 72/60 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7214-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 75/64 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7214-ACCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 83/68 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-214-N2MA", "equiv_brand": "SKF", "level": "full", "note": "Same 70×125×24 mm envelope with catalogue ratings within 10 %; QJ 214 N2MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "QJ-214-N2PHAS", "equiv_brand": "SKF", "level": "full", "note": "Same 70×125×24 mm envelope with catalogue ratings within 10 %; QJ 214 N2PHAS is the PEEK cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7214", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7214 BEP shares the 70×125×24 mm angular-contact envelope, but catalogue C/C0 differ (120/122 kN vs 67.6/56 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-214-MA", "QJ 214 MA" ], "locale_variants": {} }, { "sku": "QJ-214-N2PHAS", "brand": "SKF", "manufacturer_designation": "QJ 214 N2PHAS", "series": "QJ200-series", "type": "angular_contact", "d_mm": 70, "D_mm": 125, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer", "dynamic_load_kN": 120, "static_load_kN": 122, "fatigue_load_limit_kN": 5.2, "limiting_speed_rpm": 9000, "max_rpm": 9000, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 214 N2PHAS is SKF's 70 mm-bore QJ four-point contact ball bearing of the QJ200 series, 70×125×24 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. glass-fibre reinforced PEEK cage, outer-ring-centred with lubrication grooves in the guiding surfaces (suffix PHAS), for very high-speed oil-air or grease lubrication. Envelope 70×125×24 mm (2.756×4.921×0.945 in), 27.5 mm radial section height, C 120 kN, C0 122 kN, Pu 5.2 kN.SKF publishes only the 9,000 r/min limiting speed for this execution, catalogue mass 1300 g. Selection figures for QJ 214 N2PHAS: the static-to-dynamic ratio C0/C is 1.02, Pu 5.2 kN is about 4 % of C, and catalogue mass works out to roughly 19 g per millimetre of bore. Load balance: C0 122 kN against C 120 kN gives a 1.02 ratio, typical of a four-point thrust-oriented design; Pu 5.2 kN enters the SKF adjusted-life equation rather than the basic rating life. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 9,000 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "crane travel and hoist drives", "turret and slewing drives", "paper-machine calender stacks" ], "failure_modes": [ "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "outer-ring creep and seat fretting where a N2-locating-slot bearing is not positively stopped", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "brinelling from pressing the ring home through the balls or from static overload", "brinelling from pressing the ring home through the balls or from static overload" ], "pitfalls": [ "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "Anti-rotation is built into QJ-214-N2PHAS: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The PHAS PEEK cage of QJ-214-N2PHAS is outer-ring-centred with lubrication grooves: feed clean oil-air or appropriate grease to the guide land and inspect groove filling at overhaul.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 214 N2PHAS as the qj slotted execution; the other order numbers of the QJ 214 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-214-N2PHAS?", "a": "QJ 214 N2PHAS measures 70 mm bore × 125 mm OD × 24 mm width (2.756 × 4.921 × 0.945 in), mass about 1300 g. SKF 17000 ratings: C 120 kN, C0 122 kN, Pu 5.2 kN, SKF publishes only the 9,000 r/min limiting speed for this execution." }, { "q": "What does the N2PHAS suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. glass-fibre reinforced PEEK cage, outer-ring-centred with lubrication grooves in the guiding surfaces (suffix PHAS), for very high-speed oil-air or grease lubrication." }, { "q": "What does QJ mean in QJ 214 N2PHAS?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." } ], "cross_ref": [ { "equiv_sku": "7214-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 67.6/56 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7214-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 72/60 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7214-BECBPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 72/60 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7214-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 72/60 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7214-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 75/64 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7214-ACCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×125×24 mm envelope, but catalogue C/C0 differ between executions (120/122 kN vs 83/68 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-214-N2MA", "equiv_brand": "SKF", "level": "full", "note": "Same 70×125×24 mm envelope with catalogue ratings within 10 %; QJ 214 N2MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "QJ-214-MA", "equiv_brand": "SKF", "level": "full", "note": "Same 70×125×24 mm envelope with catalogue ratings within 10 %; QJ 214 MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7214", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7214 BEP shares the 70×125×24 mm angular-contact envelope, but catalogue C/C0 differ (120/122 kN vs 67.6/56 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-214-N2PHAS", "QJ 214 N2PHAS" ], "locale_variants": {} }, { "sku": "QJ-314-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 314 N2MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 70, "D_mm": 150, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 200, "static_load_kN": 180, "fatigue_load_limit_kN": 7.35, "limiting_speed_rpm": 8000, "max_rpm": 8000, "weight_g": 3150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 314 N2MA is SKF's 70 mm-bore QJ four-point contact ball bearing of the QJ300 series, 70×150×35 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 70×150×35 mm (2.756×5.906×1.378 in), 40.0 mm radial section height, C 200 kN, C0 180 kN, Pu 7.35 kN.SKF publishes only the 8,000 r/min limiting speed for this execution, catalogue mass 3150 g. The 7.35 kN fatigue load limit is the equivalent-load floor for long-life adjustment; with 200/180 kN ratings and 3150 g mass this execution carries about 2.86 kN of C per millimetre of bore. Selection figures for QJ 314 N2MA: the static-to-dynamic ratio C0/C is 0.90, Pu 7.35 kN is about 4 % of C, and catalogue mass works out to roughly 45 g per millimetre of bore. Bore-to-OD planning: OD 150 over bore 70 is a 2.14× step for this size, and the 35 mm width gives a bore/width ratio of 2.00; use these ratios when housing space around the 70 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "turret and slewing drives", "paper-machine calender stacks", "heavy gearbox locating positions" ], "failure_modes": [ "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "false brinelling while the shaft stands with pure radial load and no minimum axial load", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "raceway staining from water in the lubricant during idle periods", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "The MA machined brass cage is outer-ring-centred — inspect its guide clearance when servicing", "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Anti-rotation is built into QJ-314-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-314-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 314 N2MA as the qj slotted execution; the other order numbers of the QJ 314 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-314-N2MA?", "a": "QJ 314 N2MA measures 70 mm bore × 150 mm OD × 35 mm width (2.756 × 5.906 × 1.378 in), mass about 3150 g. SKF 17000 ratings: C 200 kN, C0 180 kN, Pu 7.35 kN, SKF publishes only the 8,000 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." }, { "q": "What does QJ mean in QJ 314 N2MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." } ], "cross_ref": [ { "equiv_sku": "7314-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 119/90 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 127/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-BECBPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 127/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 127/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-BEGAPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 127/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 127/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-ACCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 143/110 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-314-MA", "equiv_brand": "SKF", "level": "full", "note": "Same 70×150×35 mm envelope with catalogue ratings within 10 %; QJ 314 MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "QJ-314-N2PHAS", "equiv_brand": "SKF", "level": "full", "note": "Same 70×150×35 mm envelope with catalogue ratings within 10 %; QJ 314 N2PHAS is the PEEK cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7314", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7314 BEP shares the 70×150×35 mm angular-contact envelope, but catalogue C/C0 differ (200/180 kN vs 119/90 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-314-N2MA", "QJ 314 N2MA" ], "locale_variants": {} }, { "sku": "QJ-314-MA", "brand": "SKF", "manufacturer_designation": "QJ 314 MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 70, "D_mm": 150, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 200, "static_load_kN": 180, "fatigue_load_limit_kN": 7.35, "limiting_speed_rpm": 8000, "max_rpm": 8000, "weight_g": 3150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 314 MA is SKF's 70 mm-bore QJ four-point contact ball bearing of the QJ300 series, 70×150×35 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 70×150×35 mm (2.756×5.906×1.378 in), 40.0 mm radial section height, C 200 kN, C0 180 kN, Pu 7.35 kN.SKF publishes only the 8,000 r/min limiting speed for this execution, catalogue mass 3150 g. Selection figures for QJ 314 MA: the static-to-dynamic ratio C0/C is 0.90, Pu 7.35 kN is about 4 % of C, and catalogue mass works out to roughly 45 g per millimetre of bore. Load balance: C0 180 kN against C 200 kN gives a 0.90 ratio, typical of a four-point thrust-oriented design; Pu 7.35 kN enters the SKF adjusted-life equation rather than the basic rating life. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 8,000 r/min limiting value is the single published ceiling. Plain outer-ring execution: this order number is delivered without N2 locating slots, so anti-rotation is solved in the housing instead — a shoulder dog, a spring-loaded key, a cover feature or an interference-free circlip arrangement. Because the outer ring deliberately runs with radial clearance and a small axial float gap, omitting positive anti-rotation invites seat fretting; the slotted N2 order number is the alternative when the housing can provide engagement pins.", "applications": [ "heavy gearbox locating positions", "screw conveyor and extruder thrust positions", "crane travel and hoist drives" ], "failure_modes": [ "axial over-travel when the outer ring is clamped instead of left with radial clearance and a small end-play gap", "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "outer-ring creep and seat fretting because the plain ring has no N2 slots and relies on housing-provided anti-rotation", "brinelling from pressing the ring home through the balls or from static overload", "brinelling from pressing the ring home through the balls or from static overload" ], "pitfalls": [ "Run the QJ as a thrust bearing with radial clearance in the housing, paired with a separate radial bearing; the QJ outer ring must not be radially clamped.", "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "The MA machined brass cage is outer-ring-centred — inspect its guide clearance when servicing", "Anti-rotation is NOT built into QJ-314-MA: without N2 slots the housing must provide a dog, keyed cover or other positive stop, since the outer ring runs radially loose by design.", "The MA brass cage of QJ-314-MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 314 MA as the qj plain execution; the other order numbers of the QJ 314 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-314-MA?", "a": "QJ 314 MA measures 70 mm bore × 150 mm OD × 35 mm width (2.756 × 5.906 × 1.378 in), mass about 3150 g. SKF 17000 ratings: C 200 kN, C0 180 kN, Pu 7.35 kN, SKF publishes only the 8,000 r/min limiting speed for this execution." }, { "q": "What does the MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What does QJ mean in QJ 314 MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." } ], "cross_ref": [ { "equiv_sku": "7314-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 119/90 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 127/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-BECBPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 127/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 127/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-BEGAPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 127/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 127/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-ACCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 143/110 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-314-N2MA", "equiv_brand": "SKF", "level": "full", "note": "Same 70×150×35 mm envelope with catalogue ratings within 10 %; QJ 314 N2MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "QJ-314-N2PHAS", "equiv_brand": "SKF", "level": "full", "note": "Same 70×150×35 mm envelope with catalogue ratings within 10 %; QJ 314 N2PHAS is the PEEK cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7314", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7314 BEP shares the 70×150×35 mm angular-contact envelope, but catalogue C/C0 differ (200/180 kN vs 119/90 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-314-MA", "QJ 314 MA" ], "locale_variants": {} }, { "sku": "QJ-314-N2PHAS", "brand": "SKF", "manufacturer_designation": "QJ 314 N2PHAS", "series": "QJ300-series", "type": "angular_contact", "d_mm": 70, "D_mm": 150, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer", "dynamic_load_kN": 200, "static_load_kN": 180, "fatigue_load_limit_kN": 7.35, "limiting_speed_rpm": 8000, "max_rpm": 8000, "weight_g": 3150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 314 N2PHAS is SKF's 70 mm-bore QJ four-point contact ball bearing of the QJ300 series, 70×150×35 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. glass-fibre reinforced PEEK cage, outer-ring-centred with lubrication grooves in the guiding surfaces (suffix PHAS), for very high-speed oil-air or grease lubrication. Envelope 70×150×35 mm (2.756×5.906×1.378 in), 40.0 mm radial section height, C 200 kN, C0 180 kN, Pu 7.35 kN.SKF publishes only the 8,000 r/min limiting speed for this execution, catalogue mass 3150 g. Load balance: C0 180 kN against C 200 kN gives a 0.90 ratio, typical of a four-point thrust-oriented design; Pu 7.35 kN enters the SKF adjusted-life equation rather than the basic rating life. Mass and section check: 3150 g inside the 70×150×35 mm outline leaves a 40.0 mm radial section, and the 180 kN static rating is 0.90× the dynamic rating — plan static safety and minimum load against those numbers rather than against sister executions. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 8,000 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "paper-machine calender stacks", "heavy gearbox locating positions", "screw conveyor and extruder thrust positions" ], "failure_modes": [ "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "false brinelling while the shaft stands with pure radial load and no minimum axial load", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "electrical pitting on VFD-driven shafts without grounding protection", "raceway staining from water in the lubricant during idle periods" ], "pitfalls": [ "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "The PHAS PEEK outer-ring-centred cage with lubrication grooves suits the highest speeds with oil-air lubrication", "Anti-rotation is built into QJ-314-N2PHAS: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The PHAS PEEK cage of QJ-314-N2PHAS is outer-ring-centred with lubrication grooves: feed clean oil-air or appropriate grease to the guide land and inspect groove filling at overhaul.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 314 N2PHAS as the qj slotted execution; the other order numbers of the QJ 314 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-314-N2PHAS?", "a": "QJ 314 N2PHAS measures 70 mm bore × 150 mm OD × 35 mm width (2.756 × 5.906 × 1.378 in), mass about 3150 g. SKF 17000 ratings: C 200 kN, C0 180 kN, Pu 7.35 kN, SKF publishes only the 8,000 r/min limiting speed for this execution." }, { "q": "What does the N2PHAS suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. glass-fibre reinforced PEEK cage, outer-ring-centred with lubrication grooves in the guiding surfaces (suffix PHAS), for very high-speed oil-air or grease lubrication." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." }, { "q": "What minimum axial load does QJ-314-N2PHAS require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." } ], "cross_ref": [ { "equiv_sku": "7314-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 119/90 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 127/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-BECBPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 127/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 127/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-BEGAPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 127/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 127/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7314-ACCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×150×35 mm envelope, but catalogue C/C0 differ between executions (200/180 kN vs 143/110 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-314-N2MA", "equiv_brand": "SKF", "level": "full", "note": "Same 70×150×35 mm envelope with catalogue ratings within 10 %; QJ 314 N2MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "QJ-314-MA", "equiv_brand": "SKF", "level": "full", "note": "Same 70×150×35 mm envelope with catalogue ratings within 10 %; QJ 314 MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7314", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7314 BEP shares the 70×150×35 mm angular-contact envelope, but catalogue C/C0 differ (200/180 kN vs 119/90 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-314-N2PHAS", "QJ 314 N2PHAS" ], "locale_variants": {} }, { "sku": "QJ-215-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 215 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 75, "D_mm": 130, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 125, "static_load_kN": 132, "fatigue_load_limit_kN": 5.6, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 1450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 215 N2MA is SKF's 75 mm-bore QJ four-point contact ball bearing of the QJ200 series, 75×130×25 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 75×130×25 mm (2.953×5.118×0.984 in), 27.5 mm radial section height, C 125 kN, C0 132 kN, Pu 5.6 kN.SKF publishes only the 8,500 r/min limiting speed for this execution, catalogue mass 1450 g. Sizing arithmetic on the 75 mm bore: 125 kN C divided by the 27.5 mm radial section height gives 4.5 kN per section millimetre; the 1450 g mass and 4 % Pu/C share frame the light-load floor for the adjusted-life check. Envelope economics: the 25 mm width over a 27.5 mm section yields 0.91 mm of ring width per section millimetre, and the bearing weighs 1450 g for 125 kN of dynamic capacity — about 12 g per rated kN. Bore-to-OD planning: OD 130 over bore 75 is a 1.73× step for this size, and the 25 mm width gives a bore/width ratio of 3.00; use these ratios when housing space around the 75 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "paper-machine calender stacks", "heavy gearbox locating positions", "screw conveyor and extruder thrust positions" ], "failure_modes": [ "cage wear from speed above the limiting value with thin or aged lubricant", "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "fretting corrosion on a loose rotating shaft seat", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "Anti-rotation is built into QJ-215-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-215-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 215 N2MA as the qj slotted execution; the other order numbers of the QJ 215 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-215-N2MA?", "a": "QJ 215 N2MA measures 75 mm bore × 130 mm OD × 25 mm width (2.953 × 5.118 × 0.984 in), mass about 1450 g. SKF 17000 ratings: C 125 kN, C0 132 kN, Pu 5.6 kN, SKF publishes only the 8,500 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." }, { "q": "What does QJ mean in QJ 215 N2MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." } ], "cross_ref": [ { "equiv_sku": "7215-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×130×25 mm envelope, but catalogue C/C0 differ between executions (125/132 kN vs 70.2/60 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7215-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×130×25 mm envelope, but catalogue C/C0 differ between executions (125/132 kN vs 73.5/65.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7215-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×130×25 mm envelope, but catalogue C/C0 differ between executions (125/132 kN vs 73.5/65.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7215-BECBPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×130×25 mm envelope, but catalogue C/C0 differ between executions (125/132 kN vs 73.5/65.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7215-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×130×25 mm envelope, but catalogue C/C0 differ between executions (125/132 kN vs 76.5/69.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-215-MA", "equiv_brand": "SKF", "level": "full", "note": "Same 75×130×25 mm envelope with catalogue ratings within 10 %; QJ 215 MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "QJ-215-N2PHAS", "equiv_brand": "SKF", "level": "full", "note": "Same 75×130×25 mm envelope with catalogue ratings within 10 %; QJ 215 N2PHAS is the PEEK cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7215", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7215 BEP shares the 75×130×25 mm angular-contact envelope, but catalogue C/C0 differ (125/132 kN vs 70.2/60 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-215-N2MA", "QJ 215 N2MA" ], "locale_variants": {} }, { "sku": "QJ-215-MA", "brand": "SKF", "manufacturer_designation": "QJ 215 MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 75, "D_mm": 130, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 125, "static_load_kN": 132, "fatigue_load_limit_kN": 5.6, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 1450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 215 MA is SKF's 75 mm-bore QJ four-point contact ball bearing of the QJ200 series, 75×130×25 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 75×130×25 mm (2.953×5.118×0.984 in), 27.5 mm radial section height, C 125 kN, C0 132 kN, Pu 5.6 kN.SKF publishes only the 8,500 r/min limiting speed for this execution, catalogue mass 1450 g. Envelope economics: the 25 mm width over a 27.5 mm section yields 0.91 mm of ring width per section millimetre, and the bearing weighs 1450 g for 125 kN of dynamic capacity — about 12 g per rated kN. Mass and section check: 1450 g inside the 75×130×25 mm outline leaves a 27.5 mm radial section, and the 132 kN static rating is 1.06× the dynamic rating — plan static safety and minimum load against those numbers rather than against sister executions. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 8,500 r/min limiting value is the single published ceiling. Plain outer-ring execution: this order number is delivered without N2 locating slots, so anti-rotation is solved in the housing instead — a shoulder dog, a spring-loaded key, a cover feature or an interference-free circlip arrangement. Because the outer ring deliberately runs with radial clearance and a small axial float gap, omitting positive anti-rotation invites seat fretting; the slotted N2 order number is the alternative when the housing can provide engagement pins.", "applications": [ "heavy gearbox locating positions", "screw conveyor and extruder thrust positions", "crane travel and hoist drives" ], "failure_modes": [ "axial over-travel when the outer ring is clamped instead of left with radial clearance and a small end-play gap", "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "outer-ring creep and seat fretting because the plain ring has no N2 slots and relies on housing-provided anti-rotation", "hard-particle indentation of the asymmetric raceway in unfiltered oil", "hard-particle indentation of the asymmetric raceway in unfiltered oil" ], "pitfalls": [ "Without N2 slots, provide another positive anti-rotation feature for the radially loose outer ring", "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Anti-rotation is NOT built into QJ-215-MA: without N2 slots the housing must provide a dog, keyed cover or other positive stop, since the outer ring runs radially loose by design.", "The MA brass cage of QJ-215-MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 215 MA as the qj plain execution; the other order numbers of the QJ 215 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-215-MA?", "a": "QJ 215 MA measures 75 mm bore × 130 mm OD × 25 mm width (2.953 × 5.118 × 0.984 in), mass about 1450 g. SKF 17000 ratings: C 125 kN, C0 132 kN, Pu 5.6 kN, SKF publishes only the 8,500 r/min limiting speed for this execution." }, { "q": "What does the MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What does QJ mean in QJ 215 MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." } ], "cross_ref": [ { "equiv_sku": "7215-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×130×25 mm envelope, but catalogue C/C0 differ between executions (125/132 kN vs 70.2/60 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7215-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×130×25 mm envelope, but catalogue C/C0 differ between executions (125/132 kN vs 73.5/65.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7215-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×130×25 mm envelope, but catalogue C/C0 differ between executions (125/132 kN vs 73.5/65.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7215-BECBPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×130×25 mm envelope, but catalogue C/C0 differ between executions (125/132 kN vs 73.5/65.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7215-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×130×25 mm envelope, but catalogue C/C0 differ between executions (125/132 kN vs 76.5/69.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-215-N2MA", "equiv_brand": "SKF", "level": "full", "note": "Same 75×130×25 mm envelope with catalogue ratings within 10 %; QJ 215 N2MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "QJ-215-N2PHAS", "equiv_brand": "SKF", "level": "full", "note": "Same 75×130×25 mm envelope with catalogue ratings within 10 %; QJ 215 N2PHAS is the PEEK cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7215", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7215 BEP shares the 75×130×25 mm angular-contact envelope, but catalogue C/C0 differ (125/132 kN vs 70.2/60 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-215-MA", "QJ 215 MA" ], "locale_variants": {} }, { "sku": "QJ-215-N2PHAS", "brand": "SKF", "manufacturer_designation": "QJ 215 N2PHAS", "series": "QJ200-series", "type": "angular_contact", "d_mm": 75, "D_mm": 130, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer", "dynamic_load_kN": 125, "static_load_kN": 132, "fatigue_load_limit_kN": 5.6, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 1450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 215 N2PHAS is SKF's 75 mm-bore QJ four-point contact ball bearing of the QJ200 series, 75×130×25 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. glass-fibre reinforced PEEK cage, outer-ring-centred with lubrication grooves in the guiding surfaces (suffix PHAS), for very high-speed oil-air or grease lubrication. Envelope 75×130×25 mm (2.953×5.118×0.984 in), 27.5 mm radial section height, C 125 kN, C0 132 kN, Pu 5.6 kN.SKF publishes only the 8,500 r/min limiting speed for this execution, catalogue mass 1450 g. Mass and section check: 1450 g inside the 75×130×25 mm outline leaves a 27.5 mm radial section, and the 132 kN static rating is 1.06× the dynamic rating — plan static safety and minimum load against those numbers rather than against sister executions. Load balance: C0 132 kN against C 125 kN gives a 1.06 ratio, typical of a four-point thrust-oriented design; Pu 5.6 kN enters the SKF adjusted-life equation rather than the basic rating life. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 8,500 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "heavy gearbox locating positions", "screw conveyor and extruder thrust positions", "crane travel and hoist drives" ], "failure_modes": [ "cage wear from speed above the limiting value with thin or aged lubricant", "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "The PHAS PEEK outer-ring-centred cage with lubrication grooves suits the highest speeds with oil-air lubrication", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Anti-rotation is built into QJ-215-N2PHAS: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The PHAS PEEK cage of QJ-215-N2PHAS is outer-ring-centred with lubrication grooves: feed clean oil-air or appropriate grease to the guide land and inspect groove filling at overhaul.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 215 N2PHAS as the qj slotted execution; the other order numbers of the QJ 215 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-215-N2PHAS?", "a": "QJ 215 N2PHAS measures 75 mm bore × 130 mm OD × 25 mm width (2.953 × 5.118 × 0.984 in), mass about 1450 g. SKF 17000 ratings: C 125 kN, C0 132 kN, Pu 5.6 kN, SKF publishes only the 8,500 r/min limiting speed for this execution." }, { "q": "What does the N2PHAS suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. glass-fibre reinforced PEEK cage, outer-ring-centred with lubrication grooves in the guiding surfaces (suffix PHAS), for very high-speed oil-air or grease lubrication." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." }, { "q": "What minimum axial load does QJ-215-N2PHAS require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." } ], "cross_ref": [ { "equiv_sku": "7215-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×130×25 mm envelope, but catalogue C/C0 differ between executions (125/132 kN vs 70.2/60 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7215-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×130×25 mm envelope, but catalogue C/C0 differ between executions (125/132 kN vs 73.5/65.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7215-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×130×25 mm envelope, but catalogue C/C0 differ between executions (125/132 kN vs 73.5/65.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7215-BECBPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×130×25 mm envelope, but catalogue C/C0 differ between executions (125/132 kN vs 73.5/65.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7215-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×130×25 mm envelope, but catalogue C/C0 differ between executions (125/132 kN vs 76.5/69.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-215-N2MA", "equiv_brand": "SKF", "level": "full", "note": "Same 75×130×25 mm envelope with catalogue ratings within 10 %; QJ 215 N2MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "QJ-215-MA", "equiv_brand": "SKF", "level": "full", "note": "Same 75×130×25 mm envelope with catalogue ratings within 10 %; QJ 215 MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7215", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7215 BEP shares the 75×130×25 mm angular-contact envelope, but catalogue C/C0 differ (125/132 kN vs 70.2/60 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-215-N2PHAS", "QJ 215 N2PHAS" ], "locale_variants": {} }, { "sku": "QJ-315-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 315 N2MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 75, "D_mm": 160, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 216, "static_load_kN": 200, "fatigue_load_limit_kN": 7.8, "limiting_speed_rpm": 7500, "max_rpm": 7500, "weight_g": 3900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 315 N2MA is SKF's 75 mm-bore QJ four-point contact ball bearing of the QJ300 series, 75×160×37 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 75×160×37 mm (2.953×6.299×1.457 in), 42.5 mm radial section height, C 216 kN, C0 200 kN, Pu 7.8 kN.SKF publishes only the 7,500 r/min limiting speed for this execution, catalogue mass 3900 g. At the printed limiting speed of 7,500 r/min the mean pitch diameter dm ≈ 117.5 mm implies a dn value around 881k mm·r/min; only the limiting speed is published for this execution. Speed planning distinguishes the two published ceilings mechanically: the cage and balls tolerate 7,500 r/min and no separate thermal reference is published; at dm ≈ 117.5 mm the corresponding dn is approximately 881k mm·r/min. Bore-to-OD planning: OD 160 over bore 75 is a 2.13× step for this size, and the 37 mm width gives a bore/width ratio of 2.03; use these ratios when housing space around the 75 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "heavy gearbox locating positions", "screw conveyor and extruder thrust positions", "crane travel and hoist drives" ], "failure_modes": [ "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "outer-ring creep and seat fretting where a N2-locating-slot bearing is not positively stopped", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "edge loading from shaft deflection or housing misalignment", "mounting score marks when the bearing is cocked over a burr or keyway" ], "pitfalls": [ "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Anti-rotation is built into QJ-315-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-315-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 315 N2MA as the qj slotted execution; the other order numbers of the QJ 315 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-315-N2MA?", "a": "QJ 315 N2MA measures 75 mm bore × 160 mm OD × 37 mm width (2.953 × 6.299 × 1.457 in), mass about 3900 g. SKF 17000 ratings: C 216 kN, C0 200 kN, Pu 7.8 kN, SKF publishes only the 7,500 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What minimum axial load does QJ-315-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." } ], "cross_ref": [ { "equiv_sku": "7315-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×160×37 mm envelope, but catalogue C/C0 differ between executions (216/200 kN vs 125/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7315-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×160×37 mm envelope, but catalogue C/C0 differ between executions (216/200 kN vs 132/104 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7315-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×160×37 mm envelope, but catalogue C/C0 differ between executions (216/200 kN vs 132/104 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7315-BEGAPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×160×37 mm envelope, but catalogue C/C0 differ between executions (216/200 kN vs 132/104 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7315-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×160×37 mm envelope, but catalogue C/C0 differ between executions (216/200 kN vs 132/104 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-315-N2PHAS", "equiv_brand": "SKF", "level": "full", "note": "Same 75×160×37 mm envelope with catalogue ratings within 10 %; QJ 315 N2PHAS is the PEEK cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7315", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7315 BEP shares the 75×160×37 mm angular-contact envelope, but catalogue C/C0 differ (216/200 kN vs 125/98 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-315-N2MA", "QJ 315 N2MA" ], "locale_variants": {} }, { "sku": "QJ-315-N2PHAS", "brand": "SKF", "manufacturer_designation": "QJ 315 N2PHAS", "series": "QJ300-series", "type": "angular_contact", "d_mm": 75, "D_mm": 160, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer", "dynamic_load_kN": 216, "static_load_kN": 200, "fatigue_load_limit_kN": 7.8, "limiting_speed_rpm": 7500, "max_rpm": 7500, "weight_g": 3900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 315 N2PHAS is SKF's 75 mm-bore QJ four-point contact ball bearing of the QJ300 series, 75×160×37 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. glass-fibre reinforced PEEK cage, outer-ring-centred with lubrication grooves in the guiding surfaces (suffix PHAS), for very high-speed oil-air or grease lubrication. Envelope 75×160×37 mm (2.953×6.299×1.457 in), 42.5 mm radial section height, C 216 kN, C0 200 kN, Pu 7.8 kN.SKF publishes only the 7,500 r/min limiting speed for this execution, catalogue mass 3900 g. Envelope economics: the 37 mm width over a 42.5 mm section yields 0.87 mm of ring width per section millimetre, and the bearing weighs 3900 g for 216 kN of dynamic capacity — about 18 g per rated kN. Mass and section check: 3900 g inside the 75×160×37 mm outline leaves a 42.5 mm radial section, and the 200 kN static rating is 0.93× the dynamic rating — plan static safety and minimum load against those numbers rather than against sister executions. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 7,500 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "turret and slewing drives", "paper-machine calender stacks", "heavy gearbox locating positions" ], "failure_modes": [ "axial over-travel when the outer ring is clamped instead of left with radial clearance and a small end-play gap", "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "hard-particle indentation of the asymmetric raceway in unfiltered oil", "hard-particle indentation of the asymmetric raceway in unfiltered oil" ], "pitfalls": [ "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Run the QJ as a thrust bearing with radial clearance in the housing, paired with a separate radial bearing; the QJ outer ring must not be radially clamped.", "Run the QJ as a thrust bearing with radial clearance in the housing, paired with a separate radial bearing; the QJ outer ring must not be radially clamped.", "Anti-rotation is built into QJ-315-N2PHAS: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The PHAS PEEK cage of QJ-315-N2PHAS is outer-ring-centred with lubrication grooves: feed clean oil-air or appropriate grease to the guide land and inspect groove filling at overhaul.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 315 N2PHAS as the qj slotted execution; the other order numbers of the QJ 315 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-315-N2PHAS?", "a": "QJ 315 N2PHAS measures 75 mm bore × 160 mm OD × 37 mm width (2.953 × 6.299 × 1.457 in), mass about 3900 g. SKF 17000 ratings: C 216 kN, C0 200 kN, Pu 7.8 kN, SKF publishes only the 7,500 r/min limiting speed for this execution." }, { "q": "What does the N2PHAS suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. glass-fibre reinforced PEEK cage, outer-ring-centred with lubrication grooves in the guiding surfaces (suffix PHAS), for very high-speed oil-air or grease lubrication." }, { "q": "What does QJ mean in QJ 315 N2PHAS?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." } ], "cross_ref": [ { "equiv_sku": "7315-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×160×37 mm envelope, but catalogue C/C0 differ between executions (216/200 kN vs 125/98 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7315-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×160×37 mm envelope, but catalogue C/C0 differ between executions (216/200 kN vs 132/104 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7315-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×160×37 mm envelope, but catalogue C/C0 differ between executions (216/200 kN vs 132/104 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7315-BEGAPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×160×37 mm envelope, but catalogue C/C0 differ between executions (216/200 kN vs 132/104 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7315-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 75×160×37 mm envelope, but catalogue C/C0 differ between executions (216/200 kN vs 132/104 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-315-N2MA", "equiv_brand": "SKF", "level": "full", "note": "Same 75×160×37 mm envelope with catalogue ratings within 10 %; QJ 315 N2MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7315", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7315 BEP shares the 75×160×37 mm angular-contact envelope, but catalogue C/C0 differ (216/200 kN vs 125/98 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-315-N2PHAS", "QJ 315 N2PHAS" ], "locale_variants": {} }, { "sku": "QJ-216-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 216 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 80, "D_mm": 140, "B_mm": 26, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 146, "static_load_kN": 156, "fatigue_load_limit_kN": 6.4, "limiting_speed_rpm": 8000, "max_rpm": 8000, "weight_g": 1850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 216 N2MA is SKF's 80 mm-bore QJ four-point contact ball bearing of the QJ200 series, 80×140×26 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 80×140×26 mm (3.15×5.512×1.024 in), 30.0 mm radial section height, C 146 kN, C0 156 kN, Pu 6.4 kN.SKF publishes only the 8,000 r/min limiting speed for this execution, catalogue mass 1850 g. Envelope economics: the 26 mm width over a 30.0 mm section yields 0.87 mm of ring width per section millimetre, and the bearing weighs 1850 g for 146 kN of dynamic capacity — about 13 g per rated kN. Selection figures for QJ 216 N2MA: the static-to-dynamic ratio C0/C is 1.07, Pu 6.4 kN is about 4 % of C, and catalogue mass works out to roughly 23 g per millimetre of bore. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 8,000 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "turret and slewing drives", "paper-machine calender stacks", "heavy gearbox locating positions" ], "failure_modes": [ "false brinelling while the shaft stands with pure radial load and no minimum axial load", "cage wear from speed above the limiting value with thin or aged lubricant", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "hard-particle indentation of the asymmetric raceway in unfiltered oil", "brinelling from pressing the ring home through the balls or from static overload" ], "pitfalls": [ "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Anti-rotation is built into QJ-216-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-216-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 216 N2MA as the qj slotted execution; the other order numbers of the QJ 216 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-216-N2MA?", "a": "QJ 216 N2MA measures 80 mm bore × 140 mm OD × 26 mm width (3.15 × 5.512 × 1.024 in), mass about 1850 g. SKF 17000 ratings: C 146 kN, C0 156 kN, Pu 6.4 kN, SKF publishes only the 8,000 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What does QJ mean in QJ 216 N2MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." } ], "cross_ref": [ { "equiv_sku": "7216-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×140×26 mm envelope, but catalogue C/C0 differ between executions (146/156 kN vs 80.6/69.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7216-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×140×26 mm envelope, but catalogue C/C0 differ between executions (146/156 kN vs 85/75 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7216-BECBPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×140×26 mm envelope, but catalogue C/C0 differ between executions (146/156 kN vs 85/75 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7216-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×140×26 mm envelope, but catalogue C/C0 differ between executions (146/156 kN vs 85/75 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7216-BEGAPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×140×26 mm envelope, but catalogue C/C0 differ between executions (146/156 kN vs 85/75 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7216-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×140×26 mm envelope, but catalogue C/C0 differ between executions (146/156 kN vs 85/75 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-216-MA", "equiv_brand": "SKF", "level": "full", "note": "Same 80×140×26 mm envelope with catalogue ratings within 10 %; QJ 216 MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7216", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7216 BEP shares the 80×140×26 mm angular-contact envelope, but catalogue C/C0 differ (146/156 kN vs 80.6/69.5 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-216-N2MA", "QJ 216 N2MA" ], "locale_variants": {} }, { "sku": "QJ-216-MA", "brand": "SKF", "manufacturer_designation": "QJ 216 MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 80, "D_mm": 140, "B_mm": 26, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 146, "static_load_kN": 156, "fatigue_load_limit_kN": 6.4, "limiting_speed_rpm": 8000, "max_rpm": 8000, "weight_g": 1850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 216 MA is SKF's 80 mm-bore QJ four-point contact ball bearing of the QJ200 series, 80×140×26 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 80×140×26 mm (3.15×5.512×1.024 in), 30.0 mm radial section height, C 146 kN, C0 156 kN, Pu 6.4 kN.SKF publishes only the 8,000 r/min limiting speed for this execution, catalogue mass 1850 g. The 6.4 kN fatigue load limit is the equivalent-load floor for long-life adjustment; with 146/156 kN ratings and 1850 g mass this execution carries about 1.82 kN of C per millimetre of bore. Sizing arithmetic on the 80 mm bore: 146 kN C divided by the 30.0 mm radial section height gives 4.9 kN per section millimetre; the 1850 g mass and 4 % Pu/C share frame the light-load floor for the adjusted-life check. Bore-to-OD planning: OD 140 over bore 80 is a 1.75× step for this size, and the 26 mm width gives a bore/width ratio of 3.08; use these ratios when housing space around the 80 mm shaft is the first constraint. Plain outer-ring execution: this order number is delivered without N2 locating slots, so anti-rotation is solved in the housing instead — a shoulder dog, a spring-loaded key, a cover feature or an interference-free circlip arrangement. Because the outer ring deliberately runs with radial clearance and a small axial float gap, omitting positive anti-rotation invites seat fretting; the slotted N2 order number is the alternative when the housing can provide engagement pins.", "applications": [ "screw conveyor and extruder thrust positions", "crane travel and hoist drives", "turret and slewing drives" ], "failure_modes": [ "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "false brinelling while the shaft stands with pure radial load and no minimum axial load", "outer-ring creep and seat fretting because the plain ring has no N2 slots and relies on housing-provided anti-rotation", "raceway staining from water in the lubricant during idle periods", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "Anti-rotation is NOT built into QJ-216-MA: without N2 slots the housing must provide a dog, keyed cover or other positive stop, since the outer ring runs radially loose by design.", "The MA brass cage of QJ-216-MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 216 MA as the qj plain execution; the other order numbers of the QJ 216 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-216-MA?", "a": "QJ 216 MA measures 80 mm bore × 140 mm OD × 26 mm width (3.15 × 5.512 × 1.024 in), mass about 1850 g. SKF 17000 ratings: C 146 kN, C0 156 kN, Pu 6.4 kN, SKF publishes only the 8,000 r/min limiting speed for this execution." }, { "q": "What does the MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." }, { "q": "What does QJ mean in QJ 216 MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." } ], "cross_ref": [ { "equiv_sku": "7216-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×140×26 mm envelope, but catalogue C/C0 differ between executions (146/156 kN vs 80.6/69.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7216-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×140×26 mm envelope, but catalogue C/C0 differ between executions (146/156 kN vs 85/75 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7216-BECBPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×140×26 mm envelope, but catalogue C/C0 differ between executions (146/156 kN vs 85/75 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7216-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×140×26 mm envelope, but catalogue C/C0 differ between executions (146/156 kN vs 85/75 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7216-BEGAPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×140×26 mm envelope, but catalogue C/C0 differ between executions (146/156 kN vs 85/75 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7216-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×140×26 mm envelope, but catalogue C/C0 differ between executions (146/156 kN vs 85/75 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-216-N2MA", "equiv_brand": "SKF", "level": "full", "note": "Same 80×140×26 mm envelope with catalogue ratings within 10 %; QJ 216 N2MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7216", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7216 BEP shares the 80×140×26 mm angular-contact envelope, but catalogue C/C0 differ (146/156 kN vs 80.6/69.5 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-216-MA", "QJ 216 MA" ], "locale_variants": {} }, { "sku": "QJ-316-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 316 N2MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 80, "D_mm": 170, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 232, "static_load_kN": 228, "fatigue_load_limit_kN": 8.65, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 4600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 316 N2MA is SKF's 80 mm-bore QJ four-point contact ball bearing of the QJ300 series, 80×170×39 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 80×170×39 mm (3.15×6.693×1.535 in), 45.0 mm radial section height, C 232 kN, C0 228 kN, Pu 8.65 kN.SKF publishes only the 7,000 r/min limiting speed for this execution, catalogue mass 4600 g. Load balance: C0 228 kN against C 232 kN gives a 0.98 ratio, typical of a four-point thrust-oriented design; Pu 8.65 kN enters the SKF adjusted-life equation rather than the basic rating life. Speed planning distinguishes the two published ceilings mechanically: the cage and balls tolerate 7,000 r/min and no separate thermal reference is published; at dm ≈ 125.0 mm the corresponding dn is approximately 875k mm·r/min. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 7,000 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "turret and slewing drives", "paper-machine calender stacks", "heavy gearbox locating positions" ], "failure_modes": [ "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "false brinelling while the shaft stands with pure radial load and no minimum axial load", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "electrical pitting on VFD-driven shafts without grounding protection", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Anti-rotation is built into QJ-316-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-316-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 316 N2MA as the qj slotted execution; the other order numbers of the QJ 316 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-316-N2MA?", "a": "QJ 316 N2MA measures 80 mm bore × 170 mm OD × 39 mm width (3.15 × 6.693 × 1.535 in), mass about 4600 g. SKF 17000 ratings: C 232 kN, C0 228 kN, Pu 8.65 kN, SKF publishes only the 7,000 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." }, { "q": "What minimum axial load does QJ-316-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." } ], "cross_ref": [ { "equiv_sku": "7316-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×170×39 mm envelope, but catalogue C/C0 differ between executions (232/228 kN vs 135/110 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7316-BEM", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×170×39 mm envelope, but catalogue C/C0 differ between executions (232/228 kN vs 135/110 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7316-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×170×39 mm envelope, but catalogue C/C0 differ between executions (232/228 kN vs 143/118 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7316-BECBPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×170×39 mm envelope, but catalogue C/C0 differ between executions (232/228 kN vs 143/118 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7316-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×170×39 mm envelope, but catalogue C/C0 differ between executions (232/228 kN vs 143/118 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7316-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×170×39 mm envelope, but catalogue C/C0 differ between executions (232/228 kN vs 143/118 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-316-N2PHAS", "equiv_brand": "SKF", "level": "full", "note": "Same 80×170×39 mm envelope with catalogue ratings within 10 %; QJ 316 N2PHAS is the PEEK cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7316", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7316 BEP shares the 80×170×39 mm angular-contact envelope, but catalogue C/C0 differ (232/228 kN vs 135/110 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-316-N2MA", "QJ 316 N2MA" ], "locale_variants": {} }, { "sku": "QJ-316-N2PHAS", "brand": "SKF", "manufacturer_designation": "QJ 316 N2PHAS", "series": "QJ300-series", "type": "angular_contact", "d_mm": 80, "D_mm": 170, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer", "dynamic_load_kN": 232, "static_load_kN": 228, "fatigue_load_limit_kN": 8.65, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 4600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 316 N2PHAS is SKF's 80 mm-bore QJ four-point contact ball bearing of the QJ300 series, 80×170×39 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. glass-fibre reinforced PEEK cage, outer-ring-centred with lubrication grooves in the guiding surfaces (suffix PHAS), for very high-speed oil-air or grease lubrication. Envelope 80×170×39 mm (3.15×6.693×1.535 in), 45.0 mm radial section height, C 232 kN, C0 228 kN, Pu 8.65 kN.SKF publishes only the 7,000 r/min limiting speed for this execution, catalogue mass 4600 g. The 8.65 kN fatigue load limit is the equivalent-load floor for long-life adjustment; with 232/228 kN ratings and 4600 g mass this execution carries about 2.90 kN of C per millimetre of bore. Sizing arithmetic on the 80 mm bore: 232 kN C divided by the 45.0 mm radial section height gives 5.2 kN per section millimetre; the 4600 g mass and 4 % Pu/C share frame the light-load floor for the adjusted-life check. Bore-to-OD planning: OD 170 over bore 80 is a 2.13× step for this size, and the 39 mm width gives a bore/width ratio of 2.05; use these ratios when housing space around the 80 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "paper-machine calender stacks", "heavy gearbox locating positions", "screw conveyor and extruder thrust positions" ], "failure_modes": [ "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "false brinelling while the shaft stands with pure radial load and no minimum axial load", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "raceway staining from water in the lubricant during idle periods", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "The PHAS PEEK outer-ring-centred cage with lubrication grooves suits the highest speeds with oil-air lubrication", "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "Anti-rotation is built into QJ-316-N2PHAS: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The PHAS PEEK cage of QJ-316-N2PHAS is outer-ring-centred with lubrication grooves: feed clean oil-air or appropriate grease to the guide land and inspect groove filling at overhaul.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 316 N2PHAS as the qj slotted execution; the other order numbers of the QJ 316 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-316-N2PHAS?", "a": "QJ 316 N2PHAS measures 80 mm bore × 170 mm OD × 39 mm width (3.15 × 6.693 × 1.535 in), mass about 4600 g. SKF 17000 ratings: C 232 kN, C0 228 kN, Pu 8.65 kN, SKF publishes only the 7,000 r/min limiting speed for this execution." }, { "q": "What does the N2PHAS suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. glass-fibre reinforced PEEK cage, outer-ring-centred with lubrication grooves in the guiding surfaces (suffix PHAS), for very high-speed oil-air or grease lubrication." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." }, { "q": "What does QJ mean in QJ 316 N2PHAS?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." } ], "cross_ref": [ { "equiv_sku": "7316-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×170×39 mm envelope, but catalogue C/C0 differ between executions (232/228 kN vs 135/110 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7316-BEM", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×170×39 mm envelope, but catalogue C/C0 differ between executions (232/228 kN vs 135/110 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7316-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×170×39 mm envelope, but catalogue C/C0 differ between executions (232/228 kN vs 143/118 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7316-BECBPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×170×39 mm envelope, but catalogue C/C0 differ between executions (232/228 kN vs 143/118 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7316-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×170×39 mm envelope, but catalogue C/C0 differ between executions (232/228 kN vs 143/118 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7316-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 80×170×39 mm envelope, but catalogue C/C0 differ between executions (232/228 kN vs 143/118 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-316-N2MA", "equiv_brand": "SKF", "level": "full", "note": "Same 80×170×39 mm envelope with catalogue ratings within 10 %; QJ 316 N2MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7316", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7316 BEP shares the 80×170×39 mm angular-contact envelope, but catalogue C/C0 differ (232/228 kN vs 135/110 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-316-N2PHAS", "QJ 316 N2PHAS" ], "locale_variants": {} }, { "sku": "QJ-217-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 217 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 85, "D_mm": 150, "B_mm": 28, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 156, "static_load_kN": 173, "fatigue_load_limit_kN": 6.7, "limiting_speed_rpm": 7500, "max_rpm": 7500, "weight_g": 2250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 217 N2MA is SKF's 85 mm-bore QJ four-point contact ball bearing of the QJ200 series, 85×150×28 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 85×150×28 mm (3.346×5.906×1.102 in), 32.5 mm radial section height, C 156 kN, C0 173 kN, Pu 6.7 kN.SKF publishes only the 7,500 r/min limiting speed for this execution, catalogue mass 2250 g. Mass and section check: 2250 g inside the 85×150×28 mm outline leaves a 32.5 mm radial section, and the 173 kN static rating is 1.11× the dynamic rating — plan static safety and minimum load against those numbers rather than against sister executions. At the printed limiting speed of 7,500 r/min the mean pitch diameter dm ≈ 117.5 mm implies a dn value around 881k mm·r/min; only the limiting speed is published for this execution. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 7,500 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "heavy gearbox locating positions", "screw conveyor and extruder thrust positions", "crane travel and hoist drives" ], "failure_modes": [ "cage wear from speed above the limiting value with thin or aged lubricant", "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "raceway staining from water in the lubricant during idle periods" ], "pitfalls": [ "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Anti-rotation is built into QJ-217-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-217-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 217 N2MA as the qj slotted execution; the other order numbers of the QJ 217 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-217-N2MA?", "a": "QJ 217 N2MA measures 85 mm bore × 150 mm OD × 28 mm width (3.346 × 5.906 × 1.102 in), mass about 2250 g. SKF 17000 ratings: C 156 kN, C0 173 kN, Pu 6.7 kN, SKF publishes only the 7,500 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." }, { "q": "What minimum axial load does QJ-217-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." } ], "cross_ref": [ { "equiv_sku": "7217-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 85×150×28 mm envelope, but catalogue C/C0 differ between executions (156/173 kN vs 95.6/83 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7217-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 85×150×28 mm envelope, but catalogue C/C0 differ between executions (156/173 kN vs 102/90 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7217-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 85×150×28 mm envelope, but catalogue C/C0 differ between executions (156/173 kN vs 102/90 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7217-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 85×150×28 mm envelope, but catalogue C/C0 differ between executions (156/173 kN vs 102/90 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-217-MA", "equiv_brand": "SKF", "level": "full", "note": "Same 85×150×28 mm envelope with catalogue ratings within 10 %; QJ 217 MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7217", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7217 BEP shares the 85×150×28 mm angular-contact envelope, but catalogue C/C0 differ (156/173 kN vs 95.6/83 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-217-N2MA", "QJ 217 N2MA" ], "locale_variants": {} }, { "sku": "QJ-217-MA", "brand": "SKF", "manufacturer_designation": "QJ 217 MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 85, "D_mm": 150, "B_mm": 28, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 156, "static_load_kN": 173, "fatigue_load_limit_kN": 6.7, "limiting_speed_rpm": 7500, "max_rpm": 7500, "weight_g": 2250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 217 MA is SKF's 85 mm-bore QJ four-point contact ball bearing of the QJ200 series, 85×150×28 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 85×150×28 mm (3.346×5.906×1.102 in), 32.5 mm radial section height, C 156 kN, C0 173 kN, Pu 6.7 kN.SKF publishes only the 7,500 r/min limiting speed for this execution, catalogue mass 2250 g. Speed planning distinguishes the two published ceilings mechanically: the cage and balls tolerate 7,500 r/min and no separate thermal reference is published; at dm ≈ 117.5 mm the corresponding dn is approximately 881k mm·r/min. Sizing arithmetic on the 85 mm bore: 156 kN C divided by the 32.5 mm radial section height gives 4.8 kN per section millimetre; the 2250 g mass and 4 % Pu/C share frame the light-load floor for the adjusted-life check. Bore-to-OD planning: OD 150 over bore 85 is a 1.76× step for this size, and the 28 mm width gives a bore/width ratio of 3.04; use these ratios when housing space around the 85 mm shaft is the first constraint. Plain outer-ring execution: this order number is delivered without N2 locating slots, so anti-rotation is solved in the housing instead — a shoulder dog, a spring-loaded key, a cover feature or an interference-free circlip arrangement. Because the outer ring deliberately runs with radial clearance and a small axial float gap, omitting positive anti-rotation invites seat fretting; the slotted N2 order number is the alternative when the housing can provide engagement pins.", "applications": [ "heavy gearbox locating positions", "screw conveyor and extruder thrust positions", "crane travel and hoist drives" ], "failure_modes": [ "axial over-travel when the outer ring is clamped instead of left with radial clearance and a small end-play gap", "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "outer-ring creep and seat fretting because the plain ring has no N2 slots and relies on housing-provided anti-rotation", "mounting score marks when the bearing is cocked over a burr or keyway", "mounting score marks when the bearing is cocked over a burr or keyway" ], "pitfalls": [ "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Anti-rotation is NOT built into QJ-217-MA: without N2 slots the housing must provide a dog, keyed cover or other positive stop, since the outer ring runs radially loose by design.", "The MA brass cage of QJ-217-MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 217 MA as the qj plain execution; the other order numbers of the QJ 217 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-217-MA?", "a": "QJ 217 MA measures 85 mm bore × 150 mm OD × 28 mm width (3.346 × 5.906 × 1.102 in), mass about 2250 g. SKF 17000 ratings: C 156 kN, C0 173 kN, Pu 6.7 kN, SKF publishes only the 7,500 r/min limiting speed for this execution." }, { "q": "What does the MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What minimum axial load does QJ-217-MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." } ], "cross_ref": [ { "equiv_sku": "7217-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 85×150×28 mm envelope, but catalogue C/C0 differ between executions (156/173 kN vs 95.6/83 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7217-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 85×150×28 mm envelope, but catalogue C/C0 differ between executions (156/173 kN vs 102/90 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7217-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 85×150×28 mm envelope, but catalogue C/C0 differ between executions (156/173 kN vs 102/90 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7217-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 85×150×28 mm envelope, but catalogue C/C0 differ between executions (156/173 kN vs 102/90 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-217-N2MA", "equiv_brand": "SKF", "level": "full", "note": "Same 85×150×28 mm envelope with catalogue ratings within 10 %; QJ 217 N2MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7217", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7217 BEP shares the 85×150×28 mm angular-contact envelope, but catalogue C/C0 differ (156/173 kN vs 95.6/83 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-217-MA", "QJ 217 MA" ], "locale_variants": {} }, { "sku": "QJ-317-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 317 N2MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 85, "D_mm": 180, "B_mm": 41, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 250, "static_load_kN": 255, "fatigue_load_limit_kN": 8.65, "limiting_speed_rpm": 6700, "max_rpm": 6700, "weight_g": 5450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 317 N2MA is SKF's 85 mm-bore QJ four-point contact ball bearing of the QJ300 series, 85×180×41 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 85×180×41 mm (3.346×7.087×1.614 in), 47.5 mm radial section height, C 250 kN, C0 255 kN, Pu 8.65 kN.SKF publishes only the 6,700 r/min limiting speed for this execution, catalogue mass 5450 g. Selection figures for QJ 317 N2MA: the static-to-dynamic ratio C0/C is 1.02, Pu 8.65 kN is about 3 % of C, and catalogue mass works out to roughly 64 g per millimetre of bore. Envelope economics: the 41 mm width over a 47.5 mm section yields 0.86 mm of ring width per section millimetre, and the bearing weighs 5450 g for 250 kN of dynamic capacity — about 22 g per rated kN. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 6,700 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "turret and slewing drives", "paper-machine calender stacks", "heavy gearbox locating positions" ], "failure_modes": [ "false brinelling while the shaft stands with pure radial load and no minimum axial load", "cage wear from speed above the limiting value with thin or aged lubricant", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "brinelling from pressing the ring home through the balls or from static overload", "hard-particle indentation of the asymmetric raceway in unfiltered oil" ], "pitfalls": [ "Run the QJ as a thrust bearing with radial clearance in the housing, paired with a separate radial bearing; the QJ outer ring must not be radially clamped.", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "The MA machined brass cage is outer-ring-centred — inspect its guide clearance when servicing", "Anti-rotation is built into QJ-317-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-317-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 317 N2MA as the qj slotted execution; the other order numbers of the QJ 317 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-317-N2MA?", "a": "QJ 317 N2MA measures 85 mm bore × 180 mm OD × 41 mm width (3.346 × 7.087 × 1.614 in), mass about 5450 g. SKF 17000 ratings: C 250 kN, C0 255 kN, Pu 8.65 kN, SKF publishes only the 6,700 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What does QJ mean in QJ 317 N2MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." } ], "cross_ref": [ { "equiv_sku": "7317-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 85×180×41 mm envelope, but catalogue C/C0 differ between executions (250/255 kN vs 146/122 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7317-BEM", "equiv_brand": "SKF", "level": "partial", "note": "Same 85×180×41 mm envelope, but catalogue C/C0 differ between executions (250/255 kN vs 146/122 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7317-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 85×180×41 mm envelope, but catalogue C/C0 differ between executions (250/255 kN vs 156/132 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7317-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 85×180×41 mm envelope, but catalogue C/C0 differ between executions (250/255 kN vs 156/132 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7317-BEGAPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 85×180×41 mm envelope, but catalogue C/C0 differ between executions (250/255 kN vs 156/132 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7317-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 85×180×41 mm envelope, but catalogue C/C0 differ between executions (250/255 kN vs 156/132 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7317", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7317 BEP shares the 85×180×41 mm angular-contact envelope, but catalogue C/C0 differ (250/255 kN vs 146/122 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-317-N2MA", "QJ 317 N2MA" ], "locale_variants": {} }, { "sku": "QJ-218-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 218 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 90, "D_mm": 160, "B_mm": 30, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 186, "static_load_kN": 200, "fatigue_load_limit_kN": 7.65, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 2750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 218 N2MA is SKF's 90 mm-bore QJ four-point contact ball bearing of the QJ200 series, 90×160×30 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 90×160×30 mm (3.543×6.299×1.181 in), 35.0 mm radial section height, C 186 kN, C0 200 kN, Pu 7.65 kN.SKF publishes only the 7,000 r/min limiting speed for this execution, catalogue mass 2750 g. At the printed limiting speed of 7,000 r/min the mean pitch diameter dm ≈ 125.0 mm implies a dn value around 875k mm·r/min; only the limiting speed is published for this execution. Speed planning distinguishes the two published ceilings mechanically: the cage and balls tolerate 7,000 r/min and no separate thermal reference is published; at dm ≈ 125.0 mm the corresponding dn is approximately 875k mm·r/min. Bore-to-OD planning: OD 160 over bore 90 is a 1.78× step for this size, and the 30 mm width gives a bore/width ratio of 3.00; use these ratios when housing space around the 90 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "screw conveyor and extruder thrust positions", "crane travel and hoist drives", "turret and slewing drives" ], "failure_modes": [ "axial over-travel when the outer ring is clamped instead of left with radial clearance and a small end-play gap", "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "edge loading from shaft deflection or housing misalignment", "mounting score marks when the bearing is cocked over a burr or keyway" ], "pitfalls": [ "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "Anti-rotation is built into QJ-218-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-218-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 218 N2MA as the qj slotted execution; the other order numbers of the QJ 218 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-218-N2MA?", "a": "QJ 218 N2MA measures 90 mm bore × 160 mm OD × 30 mm width (3.543 × 6.299 × 1.181 in), mass about 2750 g. SKF 17000 ratings: C 186 kN, C0 200 kN, Pu 7.65 kN, SKF publishes only the 7,000 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What minimum axial load does QJ-218-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." } ], "cross_ref": [ { "equiv_sku": "7218-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 90×160×30 mm envelope, but catalogue C/C0 differ between executions (186/200 kN vs 108/96.5 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7218-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 90×160×30 mm envelope, but catalogue C/C0 differ between executions (186/200 kN vs 116/104 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7218-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 90×160×30 mm envelope, but catalogue C/C0 differ between executions (186/200 kN vs 116/104 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7218-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 90×160×30 mm envelope, but catalogue C/C0 differ between executions (186/200 kN vs 116/104 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7218", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7218 BEP shares the 90×160×30 mm angular-contact envelope, but catalogue C/C0 differ (186/200 kN vs 108/96.5 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-218-N2MA", "QJ 218 N2MA" ], "locale_variants": {} }, { "sku": "QJ-318-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 318 N2MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 90, "D_mm": 190, "B_mm": 43, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 285, "static_load_kN": 305, "fatigue_load_limit_kN": 11, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 6450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 318 N2MA is SKF's 90 mm-bore QJ four-point contact ball bearing of the QJ300 series, 90×190×43 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 90×190×43 mm (3.543×7.48×1.693 in), 50.0 mm radial section height, C 285 kN, C0 305 kN, Pu 11 kN.SKF publishes only the 6,300 r/min limiting speed for this execution, catalogue mass 6450 g. Sizing arithmetic on the 90 mm bore: 285 kN C divided by the 50.0 mm radial section height gives 5.7 kN per section millimetre; the 6450 g mass and 4 % Pu/C share frame the light-load floor for the adjusted-life check. Envelope economics: the 43 mm width over a 50.0 mm section yields 0.86 mm of ring width per section millimetre, and the bearing weighs 6450 g for 285 kN of dynamic capacity — about 23 g per rated kN. Bore-to-OD planning: OD 190 over bore 90 is a 2.11× step for this size, and the 43 mm width gives a bore/width ratio of 2.09; use these ratios when housing space around the 90 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "paper-machine calender stacks", "heavy gearbox locating positions", "screw conveyor and extruder thrust positions" ], "failure_modes": [ "cage wear from speed above the limiting value with thin or aged lubricant", "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "fretting corrosion on a loose rotating shaft seat", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "The MA machined brass cage is outer-ring-centred — inspect its guide clearance when servicing", "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "Anti-rotation is built into QJ-318-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-318-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 318 N2MA as the qj slotted execution; the other order numbers of the QJ 318 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-318-N2MA?", "a": "QJ 318 N2MA measures 90 mm bore × 190 mm OD × 43 mm width (3.543 × 7.48 × 1.693 in), mass about 6450 g. SKF 17000 ratings: C 285 kN, C0 305 kN, Pu 11 kN, SKF publishes only the 6,300 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." }, { "q": "What does QJ mean in QJ 318 N2MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." } ], "cross_ref": [ { "equiv_sku": "7318-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 90×190×43 mm envelope, but catalogue C/C0 differ between executions (285/305 kN vs 156/134 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7318-BEM", "equiv_brand": "SKF", "level": "partial", "note": "Same 90×190×43 mm envelope, but catalogue C/C0 differ between executions (285/305 kN vs 156/134 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7318-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 90×190×43 mm envelope, but catalogue C/C0 differ between executions (285/305 kN vs 166/146 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7318-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 90×190×43 mm envelope, but catalogue C/C0 differ between executions (285/305 kN vs 166/146 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7318-BEGAPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 90×190×43 mm envelope, but catalogue C/C0 differ between executions (285/305 kN vs 166/146 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7318-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 90×190×43 mm envelope, but catalogue C/C0 differ between executions (285/305 kN vs 166/146 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-318-N2PHAS", "equiv_brand": "SKF", "level": "full", "note": "Same 90×190×43 mm envelope with catalogue ratings within 10 %; QJ 318 N2PHAS is the PEEK cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7318", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7318 BEP shares the 90×190×43 mm angular-contact envelope, but catalogue C/C0 differ (285/305 kN vs 156/134 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-318-N2MA", "QJ 318 N2MA" ], "locale_variants": {} }, { "sku": "QJ-318-N2PHAS", "brand": "SKF", "manufacturer_designation": "QJ 318 N2PHAS", "series": "QJ300-series", "type": "angular_contact", "d_mm": 90, "D_mm": 190, "B_mm": 43, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer", "dynamic_load_kN": 285, "static_load_kN": 305, "fatigue_load_limit_kN": 11, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 6450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 318 N2PHAS is SKF's 90 mm-bore QJ four-point contact ball bearing of the QJ300 series, 90×190×43 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. glass-fibre reinforced PEEK cage, outer-ring-centred with lubrication grooves in the guiding surfaces (suffix PHAS), for very high-speed oil-air or grease lubrication. Envelope 90×190×43 mm (3.543×7.48×1.693 in), 50.0 mm radial section height, C 285 kN, C0 305 kN, Pu 11 kN.SKF publishes only the 6,300 r/min limiting speed for this execution, catalogue mass 6450 g. Mass and section check: 6450 g inside the 90×190×43 mm outline leaves a 50.0 mm radial section, and the 305 kN static rating is 1.07× the dynamic rating — plan static safety and minimum load against those numbers rather than against sister executions. Load balance: C0 305 kN against C 285 kN gives a 1.07 ratio, typical of a four-point thrust-oriented design; Pu 11 kN enters the SKF adjusted-life equation rather than the basic rating life. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 6,300 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "crane travel and hoist drives", "turret and slewing drives", "paper-machine calender stacks" ], "failure_modes": [ "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "false brinelling while the shaft stands with pure radial load and no minimum axial load", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "The PHAS PEEK outer-ring-centred cage with lubrication grooves suits the highest speeds with oil-air lubrication", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "Anti-rotation is built into QJ-318-N2PHAS: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The PHAS PEEK cage of QJ-318-N2PHAS is outer-ring-centred with lubrication grooves: feed clean oil-air or appropriate grease to the guide land and inspect groove filling at overhaul.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 318 N2PHAS as the qj slotted execution; the other order numbers of the QJ 318 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-318-N2PHAS?", "a": "QJ 318 N2PHAS measures 90 mm bore × 190 mm OD × 43 mm width (3.543 × 7.48 × 1.693 in), mass about 6450 g. SKF 17000 ratings: C 285 kN, C0 305 kN, Pu 11 kN, SKF publishes only the 6,300 r/min limiting speed for this execution." }, { "q": "What does the N2PHAS suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. glass-fibre reinforced PEEK cage, outer-ring-centred with lubrication grooves in the guiding surfaces (suffix PHAS), for very high-speed oil-air or grease lubrication." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." }, { "q": "What minimum axial load does QJ-318-N2PHAS require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." } ], "cross_ref": [ { "equiv_sku": "7318-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 90×190×43 mm envelope, but catalogue C/C0 differ between executions (285/305 kN vs 156/134 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7318-BEM", "equiv_brand": "SKF", "level": "partial", "note": "Same 90×190×43 mm envelope, but catalogue C/C0 differ between executions (285/305 kN vs 156/134 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7318-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 90×190×43 mm envelope, but catalogue C/C0 differ between executions (285/305 kN vs 166/146 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7318-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 90×190×43 mm envelope, but catalogue C/C0 differ between executions (285/305 kN vs 166/146 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7318-BEGAPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 90×190×43 mm envelope, but catalogue C/C0 differ between executions (285/305 kN vs 166/146 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7318-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 90×190×43 mm envelope, but catalogue C/C0 differ between executions (285/305 kN vs 166/146 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-318-N2MA", "equiv_brand": "SKF", "level": "full", "note": "Same 90×190×43 mm envelope with catalogue ratings within 10 %; QJ 318 N2MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7318", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7318 BEP shares the 90×190×43 mm angular-contact envelope, but catalogue C/C0 differ (285/305 kN vs 156/134 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-318-N2PHAS", "QJ 318 N2PHAS" ], "locale_variants": {} }, { "sku": "QJ-219-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 219 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 95, "D_mm": 170, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 212, "static_load_kN": 232, "fatigue_load_limit_kN": 8.5, "limiting_speed_rpm": 6700, "max_rpm": 6700, "weight_g": 3350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 219 N2MA is SKF's 95 mm-bore QJ four-point contact ball bearing of the QJ200 series, 95×170×32 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 95×170×32 mm (3.74×6.693×1.26 in), 37.5 mm radial section height, C 212 kN, C0 232 kN, Pu 8.5 kN.SKF publishes only the 6,700 r/min limiting speed for this execution, catalogue mass 3350 g. The 8.5 kN fatigue load limit is the equivalent-load floor for long-life adjustment; with 212/232 kN ratings and 3350 g mass this execution carries about 2.23 kN of C per millimetre of bore. Selection figures for QJ 219 N2MA: the static-to-dynamic ratio C0/C is 1.09, Pu 8.5 kN is about 4 % of C, and catalogue mass works out to roughly 35 g per millimetre of bore. Bore-to-OD planning: OD 170 over bore 95 is a 1.79× step for this size, and the 32 mm width gives a bore/width ratio of 2.97; use these ratios when housing space around the 95 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "crane travel and hoist drives", "turret and slewing drives", "paper-machine calender stacks" ], "failure_modes": [ "outer-ring creep and seat fretting where a N2-locating-slot bearing is not positively stopped", "axial over-travel when the outer ring is clamped instead of left with radial clearance and a small end-play gap", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "raceway staining from water in the lubricant during idle periods", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "Anti-rotation is built into QJ-219-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-219-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 219 N2MA as the qj slotted execution; the other order numbers of the QJ 219 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-219-N2MA?", "a": "QJ 219 N2MA measures 95 mm bore × 170 mm OD × 32 mm width (3.74 × 6.693 × 1.26 in), mass about 3350 g. SKF 17000 ratings: C 212 kN, C0 232 kN, Pu 8.5 kN, SKF publishes only the 6,700 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." }, { "q": "What does QJ mean in QJ 219 N2MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." } ], "cross_ref": [ { "equiv_sku": "7219-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 95×170×32 mm envelope, but catalogue C/C0 differ between executions (212/232 kN vs 124/108 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7219-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 95×170×32 mm envelope, but catalogue C/C0 differ between executions (212/232 kN vs 129/118 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7219-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 95×170×32 mm envelope, but catalogue C/C0 differ between executions (212/232 kN vs 129/118 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7219-BEGAPH", "equiv_brand": "SKF", "level": "partial", "note": "Same 95×170×32 mm envelope, but catalogue C/C0 differ between executions (212/232 kN vs 129/118 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7219-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 95×170×32 mm envelope, but catalogue C/C0 differ between executions (212/232 kN vs 129/118 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7219", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7219 BEP shares the 95×170×32 mm angular-contact envelope, but catalogue C/C0 differ (212/232 kN vs 124/108 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-219-N2MA", "QJ 219 N2MA" ], "locale_variants": {} }, { "sku": "QJ-319-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 319 N2MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 95, "D_mm": 200, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 305, "static_load_kN": 340, "fatigue_load_limit_kN": 11.8, "limiting_speed_rpm": 6000, "max_rpm": 6000, "weight_g": 7450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 319 N2MA is SKF's 95 mm-bore QJ four-point contact ball bearing of the QJ300 series, 95×200×45 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 95×200×45 mm (3.74×7.874×1.772 in), 52.5 mm radial section height, C 305 kN, C0 340 kN, Pu 11.8 kN.SKF publishes only the 6,000 r/min limiting speed for this execution, catalogue mass 7450 g. Speed planning distinguishes the two published ceilings mechanically: the cage and balls tolerate 6,000 r/min and no separate thermal reference is published; at dm ≈ 147.5 mm the corresponding dn is approximately 885k mm·r/min. At the printed limiting speed of 6,000 r/min the mean pitch diameter dm ≈ 147.5 mm implies a dn value around 885k mm·r/min; only the limiting speed is published for this execution. Bore-to-OD planning: OD 200 over bore 95 is a 2.11× step for this size, and the 45 mm width gives a bore/width ratio of 2.11; use these ratios when housing space around the 95 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "screw conveyor and extruder thrust positions", "crane travel and hoist drives", "turret and slewing drives" ], "failure_modes": [ "axial over-travel when the outer ring is clamped instead of left with radial clearance and a small end-play gap", "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "mounting score marks when the bearing is cocked over a burr or keyway", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Run the QJ as a thrust bearing with radial clearance in the housing, paired with a separate radial bearing; the QJ outer ring must not be radially clamped.", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "Anti-rotation is built into QJ-319-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-319-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 319 N2MA as the qj slotted execution; the other order numbers of the QJ 319 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-319-N2MA?", "a": "QJ 319 N2MA measures 95 mm bore × 200 mm OD × 45 mm width (3.74 × 7.874 × 1.772 in), mass about 7450 g. SKF 17000 ratings: C 305 kN, C0 340 kN, Pu 11.8 kN, SKF publishes only the 6,000 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What minimum axial load does QJ-319-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." } ], "cross_ref": [ { "equiv_sku": "7319-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 95×200×45 mm envelope, but catalogue C/C0 differ between executions (305/340 kN vs 168/150 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7319-BEM", "equiv_brand": "SKF", "level": "partial", "note": "Same 95×200×45 mm envelope, but catalogue C/C0 differ between executions (305/340 kN vs 168/150 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7319-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 95×200×45 mm envelope, but catalogue C/C0 differ between executions (305/340 kN vs 180/163 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7319-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 95×200×45 mm envelope, but catalogue C/C0 differ between executions (305/340 kN vs 180/163 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7319-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 95×200×45 mm envelope, but catalogue C/C0 differ between executions (305/340 kN vs 180/163 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-319-N2PHAS", "equiv_brand": "SKF", "level": "full", "note": "Same 95×200×45 mm envelope with catalogue ratings within 10 %; QJ 319 N2PHAS is the PEEK cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7319", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7319 BEP shares the 95×200×45 mm angular-contact envelope, but catalogue C/C0 differ (305/340 kN vs 168/150 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-319-N2MA", "QJ 319 N2MA" ], "locale_variants": {} }, { "sku": "QJ-319-N2PHAS", "brand": "SKF", "manufacturer_designation": "QJ 319 N2PHAS", "series": "QJ300-series", "type": "angular_contact", "d_mm": 95, "D_mm": 200, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer", "dynamic_load_kN": 305, "static_load_kN": 340, "fatigue_load_limit_kN": 11.8, "limiting_speed_rpm": 6000, "max_rpm": 6000, "weight_g": 7450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 319 N2PHAS is SKF's 95 mm-bore QJ four-point contact ball bearing of the QJ300 series, 95×200×45 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. glass-fibre reinforced PEEK cage, outer-ring-centred with lubrication grooves in the guiding surfaces (suffix PHAS), for very high-speed oil-air or grease lubrication. Envelope 95×200×45 mm (3.74×7.874×1.772 in), 52.5 mm radial section height, C 305 kN, C0 340 kN, Pu 11.8 kN.SKF publishes only the 6,000 r/min limiting speed for this execution, catalogue mass 7450 g. Selection figures for QJ 319 N2PHAS: the static-to-dynamic ratio C0/C is 1.11, Pu 11.8 kN is about 4 % of C, and catalogue mass works out to roughly 78 g per millimetre of bore. Load balance: C0 340 kN against C 305 kN gives a 1.11 ratio, typical of a four-point thrust-oriented design; Pu 11.8 kN enters the SKF adjusted-life equation rather than the basic rating life. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 6,000 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "screw conveyor and extruder thrust positions", "crane travel and hoist drives", "turret and slewing drives" ], "failure_modes": [ "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "outer-ring creep and seat fretting where a N2-locating-slot bearing is not positively stopped", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "brinelling from pressing the ring home through the balls or from static overload", "brinelling from pressing the ring home through the balls or from static overload" ], "pitfalls": [ "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Run the QJ as a thrust bearing with radial clearance in the housing, paired with a separate radial bearing; the QJ outer ring must not be radially clamped.", "Run the QJ as a thrust bearing with radial clearance in the housing, paired with a separate radial bearing; the QJ outer ring must not be radially clamped.", "Anti-rotation is built into QJ-319-N2PHAS: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The PHAS PEEK cage of QJ-319-N2PHAS is outer-ring-centred with lubrication grooves: feed clean oil-air or appropriate grease to the guide land and inspect groove filling at overhaul.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 319 N2PHAS as the qj slotted execution; the other order numbers of the QJ 319 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-319-N2PHAS?", "a": "QJ 319 N2PHAS measures 95 mm bore × 200 mm OD × 45 mm width (3.74 × 7.874 × 1.772 in), mass about 7450 g. SKF 17000 ratings: C 305 kN, C0 340 kN, Pu 11.8 kN, SKF publishes only the 6,000 r/min limiting speed for this execution." }, { "q": "What does the N2PHAS suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. glass-fibre reinforced PEEK cage, outer-ring-centred with lubrication grooves in the guiding surfaces (suffix PHAS), for very high-speed oil-air or grease lubrication." }, { "q": "What does QJ mean in QJ 319 N2PHAS?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." } ], "cross_ref": [ { "equiv_sku": "7319-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 95×200×45 mm envelope, but catalogue C/C0 differ between executions (305/340 kN vs 168/150 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7319-BEM", "equiv_brand": "SKF", "level": "partial", "note": "Same 95×200×45 mm envelope, but catalogue C/C0 differ between executions (305/340 kN vs 168/150 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7319-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 95×200×45 mm envelope, but catalogue C/C0 differ between executions (305/340 kN vs 180/163 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7319-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 95×200×45 mm envelope, but catalogue C/C0 differ between executions (305/340 kN vs 180/163 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7319-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 95×200×45 mm envelope, but catalogue C/C0 differ between executions (305/340 kN vs 180/163 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "QJ-319-N2MA", "equiv_brand": "SKF", "level": "full", "note": "Same 95×200×45 mm envelope with catalogue ratings within 10 %; QJ 319 N2MA is the brass cage, open arrangement, four-point split-inner-ring execution of this size — boundary dimensions interchangeable, execution differs." }, { "equiv_sku": "7319", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7319 BEP shares the 95×200×45 mm angular-contact envelope, but catalogue C/C0 differ (305/340 kN vs 168/150 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-319-N2PHAS", "QJ 319 N2PHAS" ], "locale_variants": {} }, { "sku": "QJ-220-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 220 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 100, "D_mm": 180, "B_mm": 34, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 236, "static_load_kN": 265, "fatigue_load_limit_kN": 9.5, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 4050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 220 N2MA is SKF's 100 mm-bore QJ four-point contact ball bearing of the QJ200 series, 100×180×34 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 100×180×34 mm (3.937×7.087×1.339 in), 40.0 mm radial section height, C 236 kN, C0 265 kN, Pu 9.5 kN.SKF publishes only the 6,300 r/min limiting speed for this execution, catalogue mass 4050 g. Sizing arithmetic on the 100 mm bore: 236 kN C divided by the 40.0 mm radial section height gives 5.9 kN per section millimetre; the 4050 g mass and 4 % Pu/C share frame the light-load floor for the adjusted-life check. The 9.5 kN fatigue load limit is the equivalent-load floor for long-life adjustment; with 236/265 kN ratings and 4050 g mass this execution carries about 2.36 kN of C per millimetre of bore. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 6,300 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "heavy gearbox locating positions", "screw conveyor and extruder thrust positions", "crane travel and hoist drives" ], "failure_modes": [ "cage wear from speed above the limiting value with thin or aged lubricant", "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "fretting corrosion on a loose rotating shaft seat", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Anti-rotation is built into QJ-220-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-220-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 220 N2MA as the qj slotted execution; the other order numbers of the QJ 220 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-220-N2MA?", "a": "QJ 220 N2MA measures 100 mm bore × 180 mm OD × 34 mm width (3.937 × 7.087 × 1.339 in), mass about 4050 g. SKF 17000 ratings: C 236 kN, C0 265 kN, Pu 9.5 kN, SKF publishes only the 6,300 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." }, { "q": "What does QJ mean in QJ 220 N2MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." } ], "cross_ref": [ { "equiv_sku": "7220-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 100×180×34 mm envelope, but catalogue C/C0 differ between executions (236/265 kN vs 135/122 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7220-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 100×180×34 mm envelope, but catalogue C/C0 differ between executions (236/265 kN vs 143/134 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7220-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 100×180×34 mm envelope, but catalogue C/C0 differ between executions (236/265 kN vs 143/134 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7220-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 100×180×34 mm envelope, but catalogue C/C0 differ between executions (236/265 kN vs 143/134 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7220", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7220 BEP shares the 100×180×34 mm angular-contact envelope, but catalogue C/C0 differ (236/265 kN vs 135/122 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-220-N2MA", "QJ 220 N2MA" ], "locale_variants": {} }, { "sku": "QJ-320-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 320 N2MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 100, "D_mm": 215, "B_mm": 47, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 345, "static_load_kN": 400, "fatigue_load_limit_kN": 13.7, "limiting_speed_rpm": 5600, "max_rpm": 5600, "weight_g": 9300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 320 N2MA is SKF's 100 mm-bore QJ four-point contact ball bearing of the QJ300 series, 100×215×47 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 100×215×47 mm (3.937×8.465×1.85 in), 57.5 mm radial section height, C 345 kN, C0 400 kN, Pu 13.7 kN.SKF publishes only the 5,600 r/min limiting speed for this execution, catalogue mass 9300 g. At the printed limiting speed of 5,600 r/min the mean pitch diameter dm ≈ 157.5 mm implies a dn value around 882k mm·r/min; only the limiting speed is published for this execution. The 13.7 kN fatigue load limit is the equivalent-load floor for long-life adjustment; with 345/400 kN ratings and 9300 g mass this execution carries about 3.45 kN of C per millimetre of bore. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 5,600 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "heavy gearbox locating positions", "screw conveyor and extruder thrust positions", "crane travel and hoist drives" ], "failure_modes": [ "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "outer-ring creep and seat fretting where a N2-locating-slot bearing is not positively stopped", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "edge loading from shaft deflection or housing misalignment", "mounting score marks when the bearing is cocked over a burr or keyway" ], "pitfalls": [ "Run the QJ as a thrust bearing with radial clearance in the housing, paired with a separate radial bearing; the QJ outer ring must not be radially clamped.", "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Anti-rotation is built into QJ-320-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-320-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 320 N2MA as the qj slotted execution; the other order numbers of the QJ 320 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-320-N2MA?", "a": "QJ 320 N2MA measures 100 mm bore × 215 mm OD × 47 mm width (3.937 × 8.465 × 1.85 in), mass about 9300 g. SKF 17000 ratings: C 345 kN, C0 400 kN, Pu 13.7 kN, SKF publishes only the 5,600 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What minimum axial load does QJ-320-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." } ], "cross_ref": [ { "equiv_sku": "7320-BEM", "equiv_brand": "SKF", "level": "partial", "note": "Same 100×215×47 mm envelope, but catalogue C/C0 differ between executions (345/400 kN vs 203/190 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7320-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 100×215×47 mm envelope, but catalogue C/C0 differ between executions (345/400 kN vs 203/190 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7320-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 100×215×47 mm envelope, but catalogue C/C0 differ between executions (345/400 kN vs 216/208 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7320-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 100×215×47 mm envelope, but catalogue C/C0 differ between executions (345/400 kN vs 216/208 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7320-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 100×215×47 mm envelope, but catalogue C/C0 differ between executions (345/400 kN vs 216/208 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7320", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7320 BEP shares the 100×215×47 mm angular-contact envelope, but catalogue C/C0 differ (345/400 kN vs 203/190 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-320-N2MA", "QJ 320 N2MA" ], "locale_variants": {} }, { "sku": "QJ-222-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 222 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 110, "D_mm": 200, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 280, "static_load_kN": 325, "fatigue_load_limit_kN": 11.2, "limiting_speed_rpm": 5600, "max_rpm": 5600, "weight_g": 5600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 222 N2MA is SKF's 110 mm-bore QJ four-point contact ball bearing of the QJ200 series, 110×200×38 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 110×200×38 mm (4.331×7.874×1.496 in), 45.0 mm radial section height, C 280 kN, C0 325 kN, Pu 11.2 kN.SKF publishes only the 5,600 r/min limiting speed for this execution, catalogue mass 5600 g. Mass and section check: 5600 g inside the 110×200×38 mm outline leaves a 45.0 mm radial section, and the 325 kN static rating is 1.16× the dynamic rating — plan static safety and minimum load against those numbers rather than against sister executions. Load balance: C0 325 kN against C 280 kN gives a 1.16 ratio, typical of a four-point thrust-oriented design; Pu 11.2 kN enters the SKF adjusted-life equation rather than the basic rating life. Bore-to-OD planning: OD 200 over bore 110 is a 1.82× step for this size, and the 38 mm width gives a bore/width ratio of 2.89; use these ratios when housing space around the 110 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "turret and slewing drives", "paper-machine calender stacks", "heavy gearbox locating positions" ], "failure_modes": [ "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "false brinelling while the shaft stands with pure radial load and no minimum axial load", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "raceway staining from water in the lubricant during idle periods" ], "pitfalls": [ "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "The MA machined brass cage is outer-ring-centred — inspect its guide clearance when servicing", "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "Anti-rotation is built into QJ-222-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-222-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 222 N2MA as the qj slotted execution; the other order numbers of the QJ 222 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-222-N2MA?", "a": "QJ 222 N2MA measures 110 mm bore × 200 mm OD × 38 mm width (4.331 × 7.874 × 1.496 in), mass about 5600 g. SKF 17000 ratings: C 280 kN, C0 325 kN, Pu 11.2 kN, SKF publishes only the 5,600 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." }, { "q": "What minimum axial load does QJ-222-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." } ], "cross_ref": [ { "equiv_sku": "7222-BEP", "equiv_brand": "SKF", "level": "partial", "note": "Same 110×200×38 mm envelope, but catalogue C/C0 differ between executions (280/325 kN vs 153/143 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7222-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 110×200×38 mm envelope, but catalogue C/C0 differ between executions (280/325 kN vs 163/156 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7222-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 110×200×38 mm envelope, but catalogue C/C0 differ between executions (280/325 kN vs 163/156 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7222-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 110×200×38 mm envelope, but catalogue C/C0 differ between executions (280/325 kN vs 163/156 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7222", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7222 BEP shares the 110×200×38 mm angular-contact envelope, but catalogue C/C0 differ (280/325 kN vs 153/143 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-222-N2MA", "QJ 222 N2MA" ], "locale_variants": {} }, { "sku": "QJ-322-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 322 N2MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 110, "D_mm": 240, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 390, "static_load_kN": 480, "fatigue_load_limit_kN": 15.3, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 12500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 322 N2MA is SKF's 110 mm-bore QJ four-point contact ball bearing of the QJ300 series, 110×240×50 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 110×240×50 mm (4.331×9.449×1.969 in), 65.0 mm radial section height, C 390 kN, C0 480 kN, Pu 15.3 kN.SKF publishes only the 4,800 r/min limiting speed for this execution, catalogue mass 12500 g. Selection figures for QJ 322 N2MA: the static-to-dynamic ratio C0/C is 1.23, Pu 15.3 kN is about 4 % of C, and catalogue mass works out to roughly 114 g per millimetre of bore. Load balance: C0 480 kN against C 390 kN gives a 1.23 ratio, typical of a four-point thrust-oriented design; Pu 15.3 kN enters the SKF adjusted-life equation rather than the basic rating life. Bore-to-OD planning: OD 240 over bore 110 is a 2.18× step for this size, and the 50 mm width gives a bore/width ratio of 2.20; use these ratios when housing space around the 110 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "turret and slewing drives", "paper-machine calender stacks", "heavy gearbox locating positions" ], "failure_modes": [ "false brinelling while the shaft stands with pure radial load and no minimum axial load", "cage wear from speed above the limiting value with thin or aged lubricant", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "brinelling from pressing the ring home through the balls or from static overload", "hard-particle indentation of the asymmetric raceway in unfiltered oil" ], "pitfalls": [ "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "The MA machined brass cage is outer-ring-centred — inspect its guide clearance when servicing", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Anti-rotation is built into QJ-322-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-322-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 322 N2MA as the qj slotted execution; the other order numbers of the QJ 322 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-322-N2MA?", "a": "QJ 322 N2MA measures 110 mm bore × 240 mm OD × 50 mm width (4.331 × 9.449 × 1.969 in), mass about 12500 g. SKF 17000 ratings: C 390 kN, C0 480 kN, Pu 15.3 kN, SKF publishes only the 4,800 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What does QJ mean in QJ 322 N2MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." } ], "cross_ref": [ { "equiv_sku": "7322-BEY", "equiv_brand": "SKF", "level": "partial", "note": "Same 110×240×50 mm envelope, but catalogue C/C0 differ between executions (390/480 kN vs 225/224 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7322-BEM", "equiv_brand": "SKF", "level": "partial", "note": "Same 110×240×50 mm envelope, but catalogue C/C0 differ between executions (390/480 kN vs 225/224 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7322-BECBP", "equiv_brand": "SKF", "level": "partial", "note": "Same 110×240×50 mm envelope, but catalogue C/C0 differ between executions (390/480 kN vs 240/245 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7322-BECBY", "equiv_brand": "SKF", "level": "partial", "note": "Same 110×240×50 mm envelope, but catalogue C/C0 differ between executions (390/480 kN vs 240/245 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7322-BECBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 110×240×50 mm envelope, but catalogue C/C0 differ between executions (390/480 kN vs 240/245 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7322", "equiv_brand": "SKF", "level": "partial", "note": "SKF SKF 7322 BECBP shares the 110×240×50 mm angular-contact envelope, but catalogue C/C0 differ (390/480 kN vs 240/245 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-322-N2MA", "QJ 322 N2MA" ], "locale_variants": {} }, { "sku": "QJ-224-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 224 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 120, "D_mm": 215, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 300, "static_load_kN": 365, "fatigue_load_limit_kN": 12, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 6950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 224 N2MA is SKF's 120 mm-bore QJ four-point contact ball bearing of the QJ200 series, 120×215×40 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 120×215×40 mm (4.724×8.465×1.575 in), 47.5 mm radial section height, C 300 kN, C0 365 kN, Pu 12 kN.SKF publishes only the 5,000 r/min limiting speed for this execution, catalogue mass 6950 g. The 12 kN fatigue load limit is the equivalent-load floor for long-life adjustment; with 300/365 kN ratings and 6950 g mass this execution carries about 2.50 kN of C per millimetre of bore. Sizing arithmetic on the 120 mm bore: 300 kN C divided by the 47.5 mm radial section height gives 6.3 kN per section millimetre; the 6950 g mass and 4 % Pu/C share frame the light-load floor for the adjusted-life check. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 5,000 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "large gearbox thrust locations paired with cylindrical roller radial bearings", "marine transmission thrust positions", "rolling-mill adjustment mechanisms" ], "failure_modes": [ "cage wear from speed above the limiting value with thin or aged lubricant", "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "raceway staining from water in the lubricant during idle periods", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The MA machined brass cage is outer-ring-centred — inspect its guide clearance when servicing", "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "The MA machined brass cage is outer-ring-centred — inspect its guide clearance when servicing", "Anti-rotation is built into QJ-224-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-224-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 224 N2MA as the qj slotted execution; the other order numbers of the QJ 224 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-224-N2MA?", "a": "QJ 224 N2MA measures 120 mm bore × 215 mm OD × 40 mm width (4.724 × 8.465 × 1.575 in), mass about 6950 g. SKF 17000 ratings: C 300 kN, C0 365 kN, Pu 12 kN, SKF publishes only the 5,000 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." }, { "q": "What does QJ mean in QJ 224 N2MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." } ], "cross_ref": [ { "equiv_sku": "7224-BCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 120×215×40 mm envelope, but catalogue C/C0 differ between executions (300/365 kN vs 165/163 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7224-BM", "equiv_brand": "SKF", "level": "partial", "note": "Same 120×215×40 mm envelope, but catalogue C/C0 differ between executions (300/365 kN vs 165/163 kN) — boundary dimensions match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-224-N2MA", "QJ 224 N2MA" ], "locale_variants": {} }, { "sku": "QJ-324-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 324 N2MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 120, "D_mm": 260, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 415, "static_load_kN": 530, "fatigue_load_limit_kN": 16.3, "limiting_speed_rpm": 4500, "max_rpm": 4500, "weight_g": 16000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 324 N2MA is SKF's 120 mm-bore QJ four-point contact ball bearing of the QJ300 series, 120×260×55 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 120×260×55 mm (4.724×10.236×2.165 in), 70.0 mm radial section height, C 415 kN, C0 530 kN, Pu 16.3 kN.SKF publishes only the 4,500 r/min limiting speed for this execution, catalogue mass 16000 g. Speed planning distinguishes the two published ceilings mechanically: the cage and balls tolerate 4,500 r/min and no separate thermal reference is published; at dm ≈ 190.0 mm the corresponding dn is approximately 855k mm·r/min. Sizing arithmetic on the 120 mm bore: 415 kN C divided by the 70.0 mm radial section height gives 5.9 kN per section millimetre; the 16000 g mass and 4 % Pu/C share frame the light-load floor for the adjusted-life check. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 4,500 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "large gearbox thrust locations paired with cylindrical roller radial bearings", "marine transmission thrust positions", "rolling-mill adjustment mechanisms" ], "failure_modes": [ "false brinelling while the shaft stands with pure radial load and no minimum axial load", "cage wear from speed above the limiting value with thin or aged lubricant", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "mounting score marks when the bearing is cocked over a burr or keyway", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Anti-rotation is built into QJ-324-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-324-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 324 N2MA as the qj slotted execution; the other order numbers of the QJ 324 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-324-N2MA?", "a": "QJ 324 N2MA measures 120 mm bore × 260 mm OD × 55 mm width (4.724 × 10.236 × 2.165 in), mass about 16000 g. SKF 17000 ratings: C 415 kN, C0 530 kN, Pu 16.3 kN, SKF publishes only the 4,500 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What minimum axial load does QJ-324-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." } ], "cross_ref": [ { "equiv_sku": "7324-BCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 120×260×55 mm envelope, but catalogue C/C0 differ between executions (415/530 kN vs 238/250 kN) — boundary dimensions match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-324-N2MA", "QJ 324 N2MA" ], "locale_variants": {} }, { "sku": "QJ-226-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 226 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 130, "D_mm": 230, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 310, "static_load_kN": 400, "fatigue_load_limit_kN": 12.7, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 7750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 226 N2MA is SKF's 130 mm-bore QJ four-point contact ball bearing of the QJ200 series, 130×230×40 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 130×230×40 mm (5.118×9.055×1.575 in), 50.0 mm radial section height, C 310 kN, C0 400 kN, Pu 12.7 kN.SKF publishes only the 4,800 r/min limiting speed for this execution, catalogue mass 7750 g. Load balance: C0 400 kN against C 310 kN gives a 1.29 ratio, typical of a four-point thrust-oriented design; Pu 12.7 kN enters the SKF adjusted-life equation rather than the basic rating life. Mass and section check: 7750 g inside the 130×230×40 mm outline leaves a 50.0 mm radial section, and the 400 kN static rating is 1.29× the dynamic rating — plan static safety and minimum load against those numbers rather than against sister executions. Bore-to-OD planning: OD 230 over bore 130 is a 1.77× step for this size, and the 40 mm width gives a bore/width ratio of 3.25; use these ratios when housing space around the 130 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "large gearbox thrust locations paired with cylindrical roller radial bearings", "marine transmission thrust positions", "rolling-mill adjustment mechanisms" ], "failure_modes": [ "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "false brinelling while the shaft stands with pure radial load and no minimum axial load", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "electrical pitting on VFD-driven shafts without grounding protection", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Run the QJ as a thrust bearing with radial clearance in the housing, paired with a separate radial bearing; the QJ outer ring must not be radially clamped.", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "Anti-rotation is built into QJ-226-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-226-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 226 N2MA as the qj slotted execution; the other order numbers of the QJ 226 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-226-N2MA?", "a": "QJ 226 N2MA measures 130 mm bore × 230 mm OD × 40 mm width (5.118 × 9.055 × 1.575 in), mass about 7750 g. SKF 17000 ratings: C 310 kN, C0 400 kN, Pu 12.7 kN, SKF publishes only the 4,800 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." }, { "q": "What minimum axial load does QJ-226-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." } ], "cross_ref": [ { "equiv_sku": "7226-BCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 130×230×40 mm envelope, but catalogue C/C0 differ between executions (310/400 kN vs 186/193 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7226-BM", "equiv_brand": "SKF", "level": "partial", "note": "Same 130×230×40 mm envelope, but catalogue C/C0 differ between executions (310/400 kN vs 186/193 kN) — boundary dimensions match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-226-N2MA", "QJ 226 N2MA" ], "locale_variants": {} }, { "sku": "QJ-326-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 326 N2MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 130, "D_mm": 280, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 455, "static_load_kN": 610, "fatigue_load_limit_kN": 18, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 19500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 326 N2MA is SKF's 130 mm-bore QJ four-point contact ball bearing of the QJ300 series, 130×280×58 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 130×280×58 mm (5.118×11.024×2.283 in), 75.0 mm radial section height, C 455 kN, C0 610 kN, Pu 18 kN.SKF publishes only the 4,000 r/min limiting speed for this execution, catalogue mass 19500 g. Envelope economics: the 58 mm width over a 75.0 mm section yields 0.77 mm of ring width per section millimetre, and the bearing weighs 19500 g for 455 kN of dynamic capacity — about 43 g per rated kN. Mass and section check: 19500 g inside the 130×280×58 mm outline leaves a 75.0 mm radial section, and the 610 kN static rating is 1.34× the dynamic rating — plan static safety and minimum load against those numbers rather than against sister executions. Bore-to-OD planning: OD 280 over bore 130 is a 2.15× step for this size, and the 58 mm width gives a bore/width ratio of 2.24; use these ratios when housing space around the 130 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "marine transmission thrust positions", "rolling-mill adjustment mechanisms", "offshore winch and swivel drives" ], "failure_modes": [ "false brinelling while the shaft stands with pure radial load and no minimum axial load", "cage wear from speed above the limiting value with thin or aged lubricant", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "hard-particle indentation of the asymmetric raceway in unfiltered oil", "brinelling from pressing the ring home through the balls or from static overload" ], "pitfalls": [ "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "The MA machined brass cage is outer-ring-centred — inspect its guide clearance when servicing", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "Anti-rotation is built into QJ-326-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-326-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 326 N2MA as the qj slotted execution; the other order numbers of the QJ 326 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-326-N2MA?", "a": "QJ 326 N2MA measures 130 mm bore × 280 mm OD × 58 mm width (5.118 × 11.024 × 2.283 in), mass about 19500 g. SKF 17000 ratings: C 455 kN, C0 610 kN, Pu 18 kN, SKF publishes only the 4,000 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What does QJ mean in QJ 326 N2MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." } ], "cross_ref": [ { "equiv_sku": "7326-BCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 130×280×58 mm envelope, but catalogue C/C0 differ between executions (455/610 kN vs 276/305 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7326-BM", "equiv_brand": "SKF", "level": "partial", "note": "Same 130×280×58 mm envelope, but catalogue C/C0 differ between executions (455/610 kN vs 276/305 kN) — boundary dimensions match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-326-N2MA", "QJ 326 N2MA" ], "locale_variants": {} }, { "sku": "QJ-228-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 228 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 140, "D_mm": 250, "B_mm": 42, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 345, "static_load_kN": 475, "fatigue_load_limit_kN": 14.3, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 9850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 228 N2MA is SKF's 140 mm-bore QJ four-point contact ball bearing of the QJ200 series, 140×250×42 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 140×250×42 mm (5.512×9.843×1.654 in), 55.0 mm radial section height, C 345 kN, C0 475 kN, Pu 14.3 kN.SKF publishes only the 4,300 r/min limiting speed for this execution, catalogue mass 9850 g. Sizing arithmetic on the 140 mm bore: 345 kN C divided by the 55.0 mm radial section height gives 6.3 kN per section millimetre; the 9850 g mass and 4 % Pu/C share frame the light-load floor for the adjusted-life check. The 14.3 kN fatigue load limit is the equivalent-load floor for long-life adjustment; with 345/475 kN ratings and 9850 g mass this execution carries about 2.46 kN of C per millimetre of bore. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 4,300 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "offshore winch and swivel drives", "heavy converter tilt drives", "large gearbox thrust locations paired with cylindrical roller radial bearings" ], "failure_modes": [ "outer-ring creep and seat fretting where a N2-locating-slot bearing is not positively stopped", "axial over-travel when the outer ring is clamped instead of left with radial clearance and a small end-play gap", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "fretting corrosion on a loose rotating shaft seat", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "The MA machined brass cage is outer-ring-centred — inspect its guide clearance when servicing", "Run the QJ as a thrust bearing with radial clearance in the housing, paired with a separate radial bearing; the QJ outer ring must not be radially clamped.", "Anti-rotation is built into QJ-228-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-228-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 228 N2MA as the qj slotted execution; the other order numbers of the QJ 228 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-228-N2MA?", "a": "QJ 228 N2MA measures 140 mm bore × 250 mm OD × 42 mm width (5.512 × 9.843 × 1.654 in), mass about 9850 g. SKF 17000 ratings: C 345 kN, C0 475 kN, Pu 14.3 kN, SKF publishes only the 4,300 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." }, { "q": "What does QJ mean in QJ 228 N2MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." } ], "cross_ref": [ { "equiv_sku": "7228-BCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 140×250×42 mm envelope, but catalogue C/C0 differ between executions (345/475 kN vs 199/212 kN) — boundary dimensions match, not a load-rating equivalent." }, { "equiv_sku": "7228-BM", "equiv_brand": "SKF", "level": "partial", "note": "Same 140×250×42 mm envelope, but catalogue C/C0 differ between executions (345/475 kN vs 199/212 kN) — boundary dimensions match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-228-N2MA", "QJ 228 N2MA" ], "locale_variants": {} }, { "sku": "QJ-328-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 328 N2MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 140, "D_mm": 300, "B_mm": 62, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 500, "static_load_kN": 695, "fatigue_load_limit_kN": 20, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 24000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 328 N2MA is SKF's 140 mm-bore QJ four-point contact ball bearing of the QJ300 series, 140×300×62 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 140×300×62 mm (5.512×11.811×2.441 in), 80.0 mm radial section height, C 500 kN, C0 695 kN, Pu 20 kN.SKF publishes only the 3,800 r/min limiting speed for this execution, catalogue mass 24000 g. At the printed limiting speed of 3,800 r/min the mean pitch diameter dm ≈ 220.0 mm implies a dn value around 836k mm·r/min; only the limiting speed is published for this execution. The 20 kN fatigue load limit is the equivalent-load floor for long-life adjustment; with 500/695 kN ratings and 24000 g mass this execution carries about 3.57 kN of C per millimetre of bore. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 3,800 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "heavy converter tilt drives", "large gearbox thrust locations paired with cylindrical roller radial bearings", "marine transmission thrust positions" ], "failure_modes": [ "axial over-travel when the outer ring is clamped instead of left with radial clearance and a small end-play gap", "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "edge loading from shaft deflection or housing misalignment", "mounting score marks when the bearing is cocked over a burr or keyway" ], "pitfalls": [ "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Anti-rotation is built into QJ-328-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-328-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 328 N2MA as the qj slotted execution; the other order numbers of the QJ 328 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-328-N2MA?", "a": "QJ 328 N2MA measures 140 mm bore × 300 mm OD × 62 mm width (5.512 × 11.811 × 2.441 in), mass about 24000 g. SKF 17000 ratings: C 500 kN, C0 695 kN, Pu 20 kN, SKF publishes only the 3,800 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What minimum axial load does QJ-328-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." } ], "cross_ref": [ { "equiv_sku": "7328-BCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 140×300×62 mm envelope, but catalogue C/C0 differ between executions (500/695 kN vs 302/345 kN) — boundary dimensions match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-328-N2MA", "QJ 328 N2MA" ], "locale_variants": {} }, { "sku": "QJ-230-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 230 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 150, "D_mm": 270, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 400, "static_load_kN": 570, "fatigue_load_limit_kN": 16.6, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 12500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 230 N2MA is SKF's 150 mm-bore QJ four-point contact ball bearing of the QJ200 series, 150×270×45 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 150×270×45 mm (5.906×10.63×1.772 in), 60.0 mm radial section height, C 400 kN, C0 570 kN, Pu 16.6 kN.SKF publishes only the 4,000 r/min limiting speed for this execution, catalogue mass 12500 g. Envelope economics: the 45 mm width over a 60.0 mm section yields 0.75 mm of ring width per section millimetre, and the bearing weighs 12500 g for 400 kN of dynamic capacity — about 31 g per rated kN. Mass and section check: 12500 g inside the 150×270×45 mm outline leaves a 60.0 mm radial section, and the 570 kN static rating is 1.43× the dynamic rating — plan static safety and minimum load against those numbers rather than against sister executions. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 4,000 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "large gearbox thrust locations paired with cylindrical roller radial bearings", "marine transmission thrust positions", "rolling-mill adjustment mechanisms" ], "failure_modes": [ "false brinelling while the shaft stands with pure radial load and no minimum axial load", "cage wear from speed above the limiting value with thin or aged lubricant", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "hard-particle indentation of the asymmetric raceway in unfiltered oil", "hard-particle indentation of the asymmetric raceway in unfiltered oil" ], "pitfalls": [ "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Anti-rotation is built into QJ-230-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-230-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 230 N2MA as the qj slotted execution; the other order numbers of the QJ 230 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-230-N2MA?", "a": "QJ 230 N2MA measures 150 mm bore × 270 mm OD × 45 mm width (5.906 × 10.63 × 1.772 in), mass about 12500 g. SKF 17000 ratings: C 400 kN, C0 570 kN, Pu 16.6 kN, SKF publishes only the 4,000 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What does QJ mean in QJ 230 N2MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." } ], "cross_ref": [ { "equiv_sku": "7230-BCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 150×270×45 mm envelope, but catalogue C/C0 differ between executions (400/570 kN vs 216/240 kN) — boundary dimensions match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-230-N2MA", "QJ 230 N2MA" ], "locale_variants": {} }, { "sku": "QJ-330-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 330 N2MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 150, "D_mm": 320, "B_mm": 65, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 530, "static_load_kN": 765, "fatigue_load_limit_kN": 21.2, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 29000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 330 N2MA is SKF's 150 mm-bore QJ four-point contact ball bearing of the QJ300 series, 150×320×65 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 150×320×65 mm (5.906×12.598×2.559 in), 85.0 mm radial section height, C 530 kN, C0 765 kN, Pu 21.2 kN.SKF publishes only the 3,600 r/min limiting speed for this execution, catalogue mass 29000 g. Mass and section check: 29000 g inside the 150×320×65 mm outline leaves a 85.0 mm radial section, and the 765 kN static rating is 1.44× the dynamic rating — plan static safety and minimum load against those numbers rather than against sister executions. Load balance: C0 765 kN against C 530 kN gives a 1.44 ratio, typical of a four-point thrust-oriented design; Pu 21.2 kN enters the SKF adjusted-life equation rather than the basic rating life. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 3,600 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "rolling-mill adjustment mechanisms", "offshore winch and swivel drives", "heavy converter tilt drives" ], "failure_modes": [ "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "false brinelling while the shaft stands with pure radial load and no minimum axial load", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Run the QJ as a thrust bearing with radial clearance in the housing, paired with a separate radial bearing; the QJ outer ring must not be radially clamped.", "The MA machined brass cage is outer-ring-centred — inspect its guide clearance when servicing", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "Anti-rotation is built into QJ-330-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-330-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 330 N2MA as the qj slotted execution; the other order numbers of the QJ 330 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-330-N2MA?", "a": "QJ 330 N2MA measures 150 mm bore × 320 mm OD × 65 mm width (5.906 × 12.598 × 2.559 in), mass about 29000 g. SKF 17000 ratings: C 530 kN, C0 765 kN, Pu 21.2 kN, SKF publishes only the 3,600 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." }, { "q": "What minimum axial load does QJ-330-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." } ], "cross_ref": [ { "equiv_sku": "7330-BCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 150×320×65 mm envelope, but catalogue C/C0 differ between executions (530/765 kN vs 332/390 kN) — boundary dimensions match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-330-N2MA", "QJ 330 N2MA" ], "locale_variants": {} }, { "sku": "QJ-232-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 232 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 160, "D_mm": 290, "B_mm": 48, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 450, "static_load_kN": 670, "fatigue_load_limit_kN": 19, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 15500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 232 N2MA is SKF's 160 mm-bore QJ four-point contact ball bearing of the QJ200 series, 160×290×48 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 160×290×48 mm (6.299×11.417×1.89 in), 65.0 mm radial section height, C 450 kN, C0 670 kN, Pu 19 kN.SKF publishes only the 3,800 r/min limiting speed for this execution, catalogue mass 15500 g. Speed planning distinguishes the two published ceilings mechanically: the cage and balls tolerate 3,800 r/min and no separate thermal reference is published; at dm ≈ 225.0 mm the corresponding dn is approximately 855k mm·r/min. Sizing arithmetic on the 160 mm bore: 450 kN C divided by the 65.0 mm radial section height gives 6.9 kN per section millimetre; the 15500 g mass and 4 % Pu/C share frame the light-load floor for the adjusted-life check. Bore-to-OD planning: OD 290 over bore 160 is a 1.81× step for this size, and the 48 mm width gives a bore/width ratio of 3.33; use these ratios when housing space around the 160 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "marine transmission thrust positions", "rolling-mill adjustment mechanisms", "offshore winch and swivel drives" ], "failure_modes": [ "axial over-travel when the outer ring is clamped instead of left with radial clearance and a small end-play gap", "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "mounting score marks when the bearing is cocked over a burr or keyway", "mounting score marks when the bearing is cocked over a burr or keyway" ], "pitfalls": [ "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Anti-rotation is built into QJ-232-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-232-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 232 N2MA as the qj slotted execution; the other order numbers of the QJ 232 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-232-N2MA?", "a": "QJ 232 N2MA measures 160 mm bore × 290 mm OD × 48 mm width (6.299 × 11.417 × 1.89 in), mass about 15500 g. SKF 17000 ratings: C 450 kN, C0 670 kN, Pu 19 kN, SKF publishes only the 3,800 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What minimum axial load does QJ-232-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." } ], "cross_ref": [ { "equiv_sku": "7232-BCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 160×290×48 mm envelope, but catalogue C/C0 differ between executions (450/670 kN vs 255/300 kN) — boundary dimensions match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-232-N2MA", "QJ 232 N2MA" ], "locale_variants": {} }, { "sku": "QJ-332-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 332 N2MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 160, "D_mm": 340, "B_mm": 68, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 570, "static_load_kN": 880, "fatigue_load_limit_kN": 23.6, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 34500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 332 N2MA is SKF's 160 mm-bore QJ four-point contact ball bearing of the QJ300 series, 160×340×68 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 160×340×68 mm (6.299×13.386×2.677 in), 90.0 mm radial section height, C 570 kN, C0 880 kN, Pu 23.6 kN.SKF publishes only the 3,400 r/min limiting speed for this execution, catalogue mass 34500 g. Sizing arithmetic on the 160 mm bore: 570 kN C divided by the 90.0 mm radial section height gives 6.3 kN per section millimetre; the 34500 g mass and 4 % Pu/C share frame the light-load floor for the adjusted-life check. The 23.6 kN fatigue load limit is the equivalent-load floor for long-life adjustment; with 570/880 kN ratings and 34500 g mass this execution carries about 3.56 kN of C per millimetre of bore. Bore-to-OD planning: OD 340 over bore 160 is a 2.13× step for this size, and the 68 mm width gives a bore/width ratio of 2.35; use these ratios when housing space around the 160 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "marine transmission thrust positions", "rolling-mill adjustment mechanisms", "offshore winch and swivel drives" ], "failure_modes": [ "cage wear from speed above the limiting value with thin or aged lubricant", "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "fretting corrosion on a loose rotating shaft seat", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Run the QJ as a thrust bearing with radial clearance in the housing, paired with a separate radial bearing; the QJ outer ring must not be radially clamped.", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "Anti-rotation is built into QJ-332-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-332-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 332 N2MA as the qj slotted execution; the other order numbers of the QJ 332 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-332-N2MA?", "a": "QJ 332 N2MA measures 160 mm bore × 340 mm OD × 68 mm width (6.299 × 13.386 × 2.677 in), mass about 34500 g. SKF 17000 ratings: C 570 kN, C0 880 kN, Pu 23.6 kN, SKF publishes only the 3,400 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." }, { "q": "What does QJ mean in QJ 332 N2MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." } ], "cross_ref": [ { "equiv_sku": "QJ", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-332-N2MA", "QJ 332 N2MA" ], "locale_variants": {} }, { "sku": "QJ-234-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 234 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 170, "D_mm": 310, "B_mm": 52, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 455, "static_load_kN": 720, "fatigue_load_limit_kN": 20, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 19500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 234 N2MA is SKF's 170 mm-bore QJ four-point contact ball bearing of the QJ200 series, 170×310×52 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 170×310×52 mm (6.693×12.205×2.047 in), 70.0 mm radial section height, C 455 kN, C0 720 kN, Pu 20 kN.SKF publishes only the 3,400 r/min limiting speed for this execution, catalogue mass 19500 g. Selection figures for QJ 234 N2MA: the static-to-dynamic ratio C0/C is 1.58, Pu 20 kN is about 4 % of C, and catalogue mass works out to roughly 115 g per millimetre of bore. Load balance: C0 720 kN against C 455 kN gives a 1.58 ratio, typical of a four-point thrust-oriented design; Pu 20 kN enters the SKF adjusted-life equation rather than the basic rating life. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 3,400 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "heavy converter tilt drives", "large gearbox thrust locations paired with cylindrical roller radial bearings", "marine transmission thrust positions" ], "failure_modes": [ "axial over-travel when the outer ring is clamped instead of left with radial clearance and a small end-play gap", "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "brinelling from pressing the ring home through the balls or from static overload", "brinelling from pressing the ring home through the balls or from static overload" ], "pitfalls": [ "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "Anti-rotation is built into QJ-234-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-234-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 234 N2MA as the qj slotted execution; the other order numbers of the QJ 234 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-234-N2MA?", "a": "QJ 234 N2MA measures 170 mm bore × 310 mm OD × 52 mm width (6.693 × 12.205 × 2.047 in), mass about 19500 g. SKF 17000 ratings: C 455 kN, C0 720 kN, Pu 20 kN, SKF publishes only the 3,400 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What does QJ mean in QJ 234 N2MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." } ], "cross_ref": [ { "equiv_sku": "7234-BCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 170×310×52 mm envelope, but catalogue C/C0 differ between executions (455/720 kN vs 281/345 kN) — boundary dimensions match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-234-N2MA", "QJ 234 N2MA" ], "locale_variants": {} }, { "sku": "QJ-334-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 334 N2MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 170, "D_mm": 360, "B_mm": 72, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 655, "static_load_kN": 1040, "fatigue_load_limit_kN": 27, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 41500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 334 N2MA is SKF's 170 mm-bore QJ four-point contact ball bearing of the QJ300 series, 170×360×72 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 170×360×72 mm (6.693×14.173×2.835 in), 95.0 mm radial section height, C 655 kN, C0 1040 kN, Pu 27 kN.SKF publishes only the 3,200 r/min limiting speed for this execution, catalogue mass 41500 g. Load balance: C0 1040 kN against C 655 kN gives a 1.59 ratio, typical of a four-point thrust-oriented design; Pu 27 kN enters the SKF adjusted-life equation rather than the basic rating life. Mass and section check: 41500 g inside the 170×360×72 mm outline leaves a 95.0 mm radial section, and the 1040 kN static rating is 1.59× the dynamic rating — plan static safety and minimum load against those numbers rather than against sister executions. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 3,200 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "marine transmission thrust positions", "rolling-mill adjustment mechanisms", "offshore winch and swivel drives" ], "failure_modes": [ "cage wear from speed above the limiting value with thin or aged lubricant", "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "electrical pitting on VFD-driven shafts without grounding protection", "raceway staining from water in the lubricant during idle periods" ], "pitfalls": [ "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "Run the QJ as a thrust bearing with radial clearance in the housing, paired with a separate radial bearing; the QJ outer ring must not be radially clamped.", "Anti-rotation is built into QJ-334-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-334-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 334 N2MA as the qj slotted execution; the other order numbers of the QJ 334 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-334-N2MA?", "a": "QJ 334 N2MA measures 170 mm bore × 360 mm OD × 72 mm width (6.693 × 14.173 × 2.835 in), mass about 41500 g. SKF 17000 ratings: C 655 kN, C0 1040 kN, Pu 27 kN, SKF publishes only the 3,200 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." }, { "q": "What minimum axial load does QJ-334-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." } ], "cross_ref": [ { "equiv_sku": "7334-BCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 170×360×72 mm envelope, but catalogue C/C0 differ between executions (655/1040 kN vs 390/490 kN) — boundary dimensions match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-334-N2MA", "QJ 334 N2MA" ], "locale_variants": {} }, { "sku": "QJ-236-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 236 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 180, "D_mm": 320, "B_mm": 52, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 475, "static_load_kN": 765, "fatigue_load_limit_kN": 20.8, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 20500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 236 N2MA is SKF's 180 mm-bore QJ four-point contact ball bearing of the QJ200 series, 180×320×52 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 180×320×52 mm (7.087×12.598×2.047 in), 70.0 mm radial section height, C 475 kN, C0 765 kN, Pu 20.8 kN.SKF publishes only the 3,400 r/min limiting speed for this execution, catalogue mass 20500 g. At the printed limiting speed of 3,400 r/min the mean pitch diameter dm ≈ 250.0 mm implies a dn value around 850k mm·r/min; only the limiting speed is published for this execution. The 20.8 kN fatigue load limit is the equivalent-load floor for long-life adjustment; with 475/765 kN ratings and 20500 g mass this execution carries about 2.64 kN of C per millimetre of bore. Bore-to-OD planning: OD 320 over bore 180 is a 1.78× step for this size, and the 52 mm width gives a bore/width ratio of 3.46; use these ratios when housing space around the 180 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "large gearbox thrust locations paired with cylindrical roller radial bearings", "marine transmission thrust positions", "rolling-mill adjustment mechanisms" ], "failure_modes": [ "axial over-travel when the outer ring is clamped instead of left with radial clearance and a small end-play gap", "two-piece inner-ring separation damage if the split ring is pressed or heated unevenly during mounting", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "edge loading from shaft deflection or housing misalignment", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Anti-rotation is built into QJ-236-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-236-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 236 N2MA as the qj slotted execution; the other order numbers of the QJ 236 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-236-N2MA?", "a": "QJ 236 N2MA measures 180 mm bore × 320 mm OD × 52 mm width (7.087 × 12.598 × 2.047 in), mass about 20500 g. SKF 17000 ratings: C 475 kN, C0 765 kN, Pu 20.8 kN, SKF publishes only the 3,400 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What minimum axial load does QJ-236-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." } ], "cross_ref": [ { "equiv_sku": "7236-BCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 180×320×52 mm envelope, but catalogue C/C0 differ between executions (475/765 kN vs 291/375 kN) — boundary dimensions match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-236-N2MA", "QJ 236 N2MA" ], "locale_variants": {} }, { "sku": "QJ-336-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 336 N2MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 180, "D_mm": 380, "B_mm": 75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 680, "static_load_kN": 1100, "fatigue_load_limit_kN": 28, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 47500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 336 N2MA is SKF's 180 mm-bore QJ four-point contact ball bearing of the QJ300 series, 180×380×75 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 180×380×75 mm (7.087×14.961×2.953 in), 100.0 mm radial section height, C 680 kN, C0 1100 kN, Pu 28 kN.SKF publishes only the 3,000 r/min limiting speed for this execution, catalogue mass 47500 g. The 28 kN fatigue load limit is the equivalent-load floor for long-life adjustment; with 680/1100 kN ratings and 47500 g mass this execution carries about 3.78 kN of C per millimetre of bore. Sizing arithmetic on the 180 mm bore: 680 kN C divided by the 100.0 mm radial section height gives 6.8 kN per section millimetre; the 47500 g mass and 4 % Pu/C share frame the light-load floor for the adjusted-life check. Bore-to-OD planning: OD 380 over bore 180 is a 2.11× step for this size, and the 75 mm width gives a bore/width ratio of 2.40; use these ratios when housing space around the 180 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "offshore winch and swivel drives", "heavy converter tilt drives", "large gearbox thrust locations paired with cylindrical roller radial bearings" ], "failure_modes": [ "cage wear from speed above the limiting value with thin or aged lubricant", "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "raceway staining from water in the lubricant during idle periods", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The MA machined brass cage is outer-ring-centred — inspect its guide clearance when servicing", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Anti-rotation is built into QJ-336-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-336-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 336 N2MA as the qj slotted execution; the other order numbers of the QJ 336 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-336-N2MA?", "a": "QJ 336 N2MA measures 180 mm bore × 380 mm OD × 75 mm width (7.087 × 14.961 × 2.953 in), mass about 47500 g. SKF 17000 ratings: C 680 kN, C0 1100 kN, Pu 28 kN, SKF publishes only the 3,000 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "How is a QJ four-point bearing mounted?", "a": "As a thrust/locating bearing with radial clearance in the housing, paired with a separate radial bearing (commonly a cylindrical roller bearing): the QJ locates the shaft axially in both directions, the radial bearing carries radial load. Keep the outer ring unclamped with a small end-play gap; N2 slot executions use dogs to stop the outer ring turning." }, { "q": "What does QJ mean in QJ 336 N2MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." } ], "cross_ref": [ { "equiv_sku": "7336-BCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 180×380×75 mm envelope, but catalogue C/C0 differ between executions (680/1100 kN vs 410/540 kN) — boundary dimensions match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-336-N2MA", "QJ 336 N2MA" ], "locale_variants": {} }, { "sku": "QJ-238-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 238 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 190, "D_mm": 340, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 510, "static_load_kN": 850, "fatigue_load_limit_kN": 22.4, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 23500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 238 N2MA is SKF's 190 mm-bore QJ four-point contact ball bearing of the QJ200 series, 190×340×55 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 190×340×55 mm (7.48×13.386×2.165 in), 75.0 mm radial section height, C 510 kN, C0 850 kN, Pu 22.4 kN.SKF publishes only the 3,200 r/min limiting speed for this execution, catalogue mass 23500 g. Envelope economics: the 55 mm width over a 75.0 mm section yields 0.73 mm of ring width per section millimetre, and the bearing weighs 23500 g for 510 kN of dynamic capacity — about 46 g per rated kN. Mass and section check: 23500 g inside the 190×340×55 mm outline leaves a 75.0 mm radial section, and the 850 kN static rating is 1.67× the dynamic rating — plan static safety and minimum load against those numbers rather than against sister executions. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 3,200 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "heavy converter tilt drives", "large gearbox thrust locations paired with cylindrical roller radial bearings", "marine transmission thrust positions" ], "failure_modes": [ "false brinelling while the shaft stands with pure radial load and no minimum axial load", "cage wear from speed above the limiting value with thin or aged lubricant", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "hard-particle indentation of the asymmetric raceway in unfiltered oil", "hard-particle indentation of the asymmetric raceway in unfiltered oil" ], "pitfalls": [ "Provide a minimum axial load (spring preload is common) so the balls stay correctly seated at speed and light-load conditions; otherwise they skid.", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "The MA machined brass cage is outer-ring-centred — inspect its guide clearance when servicing", "Anti-rotation is built into QJ-238-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-238-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 238 N2MA as the qj slotted execution; the other order numbers of the QJ 238 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-238-N2MA?", "a": "QJ 238 N2MA measures 190 mm bore × 340 mm OD × 55 mm width (7.48 × 13.386 × 2.165 in), mass about 23500 g. SKF 17000 ratings: C 510 kN, C0 850 kN, Pu 22.4 kN, SKF publishes only the 3,200 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What does QJ mean in QJ 238 N2MA?", "a": "QJ is SKF's four-point contact design: a two-piece inner ring and gothic-arch raceways so each ball contacts at four points, giving bidirectional axial location with limited radial capacity — it must see Fa/Fr ≥ 1,27 for correct ball contact." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." } ], "cross_ref": [ { "equiv_sku": "7238-BCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 190×340×55 mm envelope, but catalogue C/C0 differ between executions (510/850 kN vs 307/405 kN) — boundary dimensions match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-238-N2MA", "QJ 238 N2MA" ], "locale_variants": {} }, { "sku": "QJ-338-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 338 N2MA", "series": "QJ300-series", "type": "angular_contact", "d_mm": 190, "D_mm": 400, "B_mm": 78, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 702, "static_load_kN": 1160, "fatigue_load_limit_kN": 28.5, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 49000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 338 N2MA is SKF's 190 mm-bore QJ four-point contact ball bearing of the QJ300 series, 190×400×78 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 190×400×78 mm (7.48×15.748×3.071 in), 105.0 mm radial section height, C 702 kN, C0 1160 kN, Pu 28.5 kN.SKF publishes only the 2,800 r/min limiting speed for this execution, catalogue mass 49000 g. Mass and section check: 49000 g inside the 190×400×78 mm outline leaves a 105.0 mm radial section, and the 1160 kN static rating is 1.65× the dynamic rating — plan static safety and minimum load against those numbers rather than against sister executions. Load balance: C0 1160 kN against C 702 kN gives a 1.65 ratio, typical of a four-point thrust-oriented design; Pu 28.5 kN enters the SKF adjusted-life equation rather than the basic rating life. Speed-ratio note for this exact unit: no thermal reference speed is listed (seal/grease life governs), so the 2,800 r/min limiting value is the single published ceiling. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "large gearbox thrust locations paired with cylindrical roller radial bearings", "marine transmission thrust positions", "rolling-mill adjustment mechanisms" ], "failure_modes": [ "cage wear from speed above the limiting value with thin or aged lubricant", "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Keep a small axial gap between the outer ring and the cover flange so it can accommodate thermal movement; never clamp the outer ring solid.", "Engage the N2 slots with housing dogs at assembly — a radially loose outer ring without positive anti-rotation creeps its seat", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Anti-rotation is built into QJ-338-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-338-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 338 N2MA as the qj slotted execution; the other order numbers of the QJ 338 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-338-N2MA?", "a": "QJ 338 N2MA measures 190 mm bore × 400 mm OD × 78 mm width (7.48 × 15.748 × 3.071 in), mass about 49000 g. SKF 17000 ratings: C 702 kN, C0 1160 kN, Pu 28.5 kN, SKF publishes only the 2,800 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." }, { "q": "What minimum axial load does QJ-338-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." } ], "cross_ref": [ { "equiv_sku": "7338-BCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 190×400×78 mm envelope, but catalogue C/C0 differ between executions (702/1160 kN vs 442/600 kN) — boundary dimensions match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-338-N2MA", "QJ 338 N2MA" ], "locale_variants": {} }, { "sku": "QJ-240-N2MA", "brand": "SKF", "manufacturer_designation": "QJ 240 N2MA", "series": "QJ200-series", "type": "angular_contact", "d_mm": 200, "D_mm": 360, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 540, "static_load_kN": 915, "fatigue_load_limit_kN": 23.2, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 28500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "QJ 240 N2MA is SKF's 200 mm-bore QJ four-point contact ball bearing of the QJ200 series, 200×360×58 mm, with a two-piece inner ring for bidirectional axial location beside a radial bearing. QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls. Envelope 200×360×58 mm (7.874×14.173×2.283 in), 80.0 mm radial section height, C 540 kN, C0 915 kN, Pu 23.2 kN.SKF publishes only the 3,000 r/min limiting speed for this execution, catalogue mass 28500 g. Load balance: C0 915 kN against C 540 kN gives a 1.69 ratio, typical of a four-point thrust-oriented design; Pu 23.2 kN enters the SKF adjusted-life equation rather than the basic rating life. Speed planning distinguishes the two published ceilings mechanically: the cage and balls tolerate 3,000 r/min and no separate thermal reference is published; at dm ≈ 280.0 mm the corresponding dn is approximately 840k mm·r/min. Bore-to-OD planning: OD 360 over bore 200 is a 1.80× step for this size, and the 58 mm width gives a bore/width ratio of 3.45; use these ratios when housing space around the 200 mm shaft is the first constraint. Locating-slot execution: the two N2 notches are milled into one outer-ring side face exactly 180 degrees apart and engaged by housing dogs or headed pins during assembly; verify dog engagement by hand before the cover goes on, deburr the slot edges after any housing rework, and re-inspect the slot roots for fretting marks at each overhaul because a dog that rides only one slot lets the outer ring walk. The slots identify this order number unmistakably: the plain MA/PHAS execution of the same bore has no notches and must be secured differently.", "applications": [ "rolling-mill adjustment mechanisms", "offshore winch and swivel drives", "heavy converter tilt drives" ], "failure_modes": [ "cage wear from speed above the limiting value with thin or aged lubricant", "ball skidding when the Fa/Fr 1,27 load-ratio condition is not met and the balls contact both sides of one raceway", "locating-slot root fretting or dog wear when only one N2 notch carries the anti-rotation torque", "electrical pitting on VFD-driven shafts without grounding protection", "raceway staining from water in the lubricant during idle periods" ], "pitfalls": [ "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "The inner ring is two-piece: handle both halves together, mount square, and do not separate the split ring unless the fitting procedure requires it.", "Apply the Fa/Fr ≥ 1,27 condition: at lower ratios the balls contact both sides of a raceway, increasing friction and shortening life — the paired radial bearing should carry the radial share.", "Anti-rotation is built into QJ-240-N2MA: check the two N2 slot faces and the engaging housing dogs at every refit, and never rely on cover friction to stop the radially loose outer ring.", "The MA brass cage of QJ-240-N2MA is outer-ring-centred: its guide land needs an uninterrupted oil film, so check lubricant reach when the bearing is used purely as a thrust location.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for QJ 240 N2MA as the qj slotted execution; the other order numbers of the QJ 240 size are different products and may carry different ratings — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of QJ-240-N2MA?", "a": "QJ 240 N2MA measures 200 mm bore × 360 mm OD × 58 mm width (7.874 × 14.173 × 2.283 in), mass about 28500 g. SKF 17000 ratings: C 540 kN, C0 915 kN, Pu 23.2 kN, SKF publishes only the 3,000 r/min limiting speed for this execution." }, { "q": "What does the N2MA suffix mean?", "a": "QJ identifies a four-point contact ball bearing with a two-piece inner ring: the gothic-arch raceways seat each ball at four points, giving axial location in both directions while a paired radial bearing carries the radial load. N2 marks two locating slots, 180° apart, in one outer-ring side face: pins or dogs engage the slots to stop the outer ring turning in its radially-clear housing bore. machined brass cage, outer-ring-centred (suffix MA), which guides on the outer ring rather than on the balls." }, { "q": "What are the N2 locating slots for?", "a": "The two slots, 180° apart in one outer-ring side face, engage housing dogs or pins to prevent the radially loose outer ring from creeping and fretting its seat. The non-N2 execution relies on other anti-rotation measures." }, { "q": "What minimum axial load does QJ-240-N2MA require?", "a": "Like angular-contact bearings the QJ needs a minimum axial load to keep the balls seated — spring preload against the outer ring is typical — and the load ratio Fa/Fr ≥ 1,27 keeps contact on one inner-ring raceway and the opposite outer-ring side." } ], "cross_ref": [ { "equiv_sku": "7240-BCBM", "equiv_brand": "SKF", "level": "partial", "note": "Same 200×360×58 mm envelope, but catalogue C/C0 differ between executions (540/915 kN vs 325/430 kN) — boundary dimensions match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "QJ-240-N2MA", "QJ 240 N2MA" ], "locale_variants": {} }, { "sku": "BA-3", "brand": "SKF", "manufacturer_designation": "BA 3", "series": "BA-series", "type": "thrust_ball", "d_mm": 3, "D_mm": 8, "B_mm": 3.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 0.806, "static_load_kN": 0.72, "fatigue_load_limit_kN": 0.027, "reference_speed_rpm": 26000, "limiting_speed_rpm": 36000, "max_rpm": 36000, "weight_g": 1, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "BA 3 is SKF's BA-series miniature single-direction thrust ball bearing for a 3 mm shaft — the BA digits give bore in millimetres directly — supplied as a shaft washer, a housing washer and a stamped sheet-steel ball-cage assembly, 3×8×3.5 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. the BA prefix marks SKF miniature thrust ball bearings for shaft diameters below 10 mm — the digits give the bore in millimetres directly, so a BA 3 fits a 3 mm shaft rather than using the two-digit bore code. BA miniatures use the standard stamped sheet-steel ball-cage assembly: two pressed steel washers retain a small ball complement, and at these dimensions the cage and washers are handled as three loose parts. Envelope 3×8×3.5 mm (0.118×0.315×0.138 in), 2.5 mm radial section, C 0.806 kN, C0 0.72 kN, Pu 0.027 kN. reference speed 26,000 r/min (thermal) and limiting speed 36,000 r/min (mechanical), catalogue mass 1 g. Load balance: C0 0.72 kN against C 0.806 kN gives a 0.89 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 0.027 kN enters the adjusted-life check. Bore-to-OD planning: OD 8 over bore 3 is a 2.67× step for this size, and the 3.5 mm height gives a bore/height ratio of 0.86; use these ratios when the housing recess around the 3 mm shaft is the first constraint. Sizing arithmetic on the 3 mm bore: 0.806 kN C over the 2.5 mm radial section gives 0.3 kN per section millimetre, and the 3.5 mm stack height is 1.40× that section — proportions typical of a BA thrust section. Mass and section check: 1 g inside the 3×8×3.5 mm outline leaves a 2.5 mm radial section, and the 0.72 kN static rating is 0.89× the dynamic rating — plan static safety and minimum preload against those figures. Envelope economics: the 3.5 mm axial height over a 2.5 mm radial section yields 0.2 kN of dynamic capacity per height millimetre, and the bearing weighs 1 g for 0.806 kN C — about 1 g per rated kN. Miniature handling note: the three BA components — shaft washer, housing washer and ball-cage assembly — are supplied loose and separate on contact, so mount the unit inside its housing recess before the shaft is offered; a dropped BA set scatters washers and balls that are nearly impossible to sort by eye, and a washer fitted reversed cannot be seen from outside once the cover is on. Service note at 3 mm bore: never grease-pack a BA bearing — one tiny dot of instrument oil on the ball set is enough, since the 1 g assembly will hydroplane its own cage out of position inside a flooded 8 mm OD recess.", "applications": [ "small vertical electric motors and fan thrust positions", "screw-jack and clamp spindles", "appliance and office-machine thrust collars" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "permanent loss of the tiny separable components during unconfined handling or a washer fitted reversed and never detected", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 3.00×10^-6; for BA 3 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 3 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "The BA 3 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 3 mm shaft has to be carried by a radial bearing mounted alongside it.", "There is no 51xxx coded size below 10 mm bore: the BA range is the miniature entry point for pure axial location, and at 3 mm the limit loads are small enough that shaft and housing squareness, not capacity, usually governs the design.", "Ordering discipline for BA 3: the catalogue page quotes BA 3 and its 0.806/0.72 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of BA-3?", "a": "BA 3 measures 3 mm bore × 8 mm OD × 3.5 mm bearing height (0.118 × 0.315 × 0.138 in), mass about 1 g. SKF 17000 ratings: C 0.806 kN, C0 0.72 kN, Pu 0.027 kN, reference speed 26,000 r/min (thermal) and limiting speed 36,000 r/min (mechanical)." }, { "q": "What does the designation BA 3 mean?", "a": "the BA prefix marks SKF miniature thrust ball bearings for shaft diameters below 10 mm — the digits give the bore in millimetres directly, so a BA 3 fits a 3 mm shaft rather than using the two-digit bore code. BA miniatures use the standard stamped sheet-steel ball-cage assembly: two pressed steel washers retain a small ball complement, and at these dimensions the cage and washers are handled as three loose parts. The BA range covers bores 3–9 mm; from 10 mm bore upwards the standard coded range begins at 51100." }, { "q": "How are BA miniature thrust bearings supplied and fitted?", "a": "As three separable components — shaft washer, housing washer and ball-cage assembly. Build the set inside the housing recess before inserting the 3 mm shaft, keep the parts in their packaging until fitting, and note the tiny C 0.806 kN rating suits instrument and light axial location duty." }, { "q": "Can BA-3 carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 3 mm shaft must go to a separate radial bearing; mixed loading through BA 3 edge-loads the balls and destroys the washers." } ], "cross_ref": [ { "equiv_sku": "BA", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "BA-3", "BA 3" ], "locale_variants": {} }, { "sku": "BA-4", "brand": "SKF", "manufacturer_designation": "BA 4", "series": "BA-series", "type": "thrust_ball", "d_mm": 4, "D_mm": 10, "B_mm": 4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 0.761, "static_load_kN": 0.72, "fatigue_load_limit_kN": 0.027, "reference_speed_rpm": 22000, "limiting_speed_rpm": 30000, "max_rpm": 30000, "weight_g": 2, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF lists BA 4 in the BA miniature range: a single-direction thrust ball bearing of 4 mm bore (stated directly in the order number), 4×10×4 mm, built from two thin pressed washers and a miniature ball-cage assembly. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. the BA numbering convention is literal for miniature sizes — BA 4 names a 4 mm shaft outright, bridging the gap where the coded 51xxx range does not yet begin. cage-wise BA bearings follow the standard pressed sheet-steel design: the retainer separates the miniature ball complement and is handled as one of the three loose components. Envelope 4×10×4 mm (0.157×0.394×0.157 in), 3.0 mm radial section, C 0.761 kN, C0 0.72 kN, Pu 0.027 kN. reference speed 22,000 r/min (thermal) and limiting speed 30,000 r/min (mechanical), catalogue mass 2 g. Speed-ratio note for this exact unit: the reference speed is 22,000 r/min against a 30,000 r/min limiting speed, a reference-to-limit ratio of 0.73. Speed band width for this size is 8,000 r/min between reference and limiting (1.36× ratio); lubrication, preload and heat removal decide where inside that band BA 4 can actually run. Pitch-diameter arithmetic: dm = (4+10)/2 = 7.0 mm; at the 30,000 r/min limiting speed that corresponds to roughly 210k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Sizing arithmetic on the 4 mm bore: 0.761 kN C over the 3.0 mm radial section gives 0.3 kN per section millimetre, and the 4 mm stack height is 1.33× that section — proportions typical of a BA thrust section. Load balance: C0 0.72 kN against C 0.761 kN gives a 0.95 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 0.027 kN enters the adjusted-life check. Miniature handling note: the three BA components — shaft washer, housing washer and ball-cage assembly — are supplied loose and separate on contact, so mount the unit inside its housing recess before the shaft is offered; a dropped BA set scatters washers and balls that are nearly impossible to sort by eye, and a washer fitted reversed cannot be seen from outside once the cover is on. Service note at 4 mm bore: never grease-pack a BA bearing — one tiny dot of instrument oil on the ball set is enough, since the 2 g assembly will hydroplane its own cage out of position inside a flooded 10 mm OD recess.", "applications": [ "small vertical electric motors and fan thrust positions", "light crane hooks and swivel pins", "instrument and indexing-table pivots" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "permanent loss of the tiny separable components during unconfined handling or a washer fitted reversed and never detected", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 3.00×10^-6; for BA 4 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The BA 4 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 4 mm shaft has to be carried by a radial bearing mounted alongside it.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 4 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 4 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "There is no 51xxx coded size below 10 mm bore: the BA range is the miniature entry point for pure axial location, and at 4 mm the limit loads are small enough that shaft and housing squareness, not capacity, usually governs the design.", "Ordering discipline for BA 4: the catalogue page quotes BA 4 and its 0.761/0.72 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of BA-4?", "a": "The catalogue envelope is 4×10×4 mm, mass 2 g; ratings C 0.761 kN / C0 0.72 kN / Pu 0.027 kN, reference speed 22,000 r/min (thermal) and limiting speed 30,000 r/min (mechanical)." }, { "q": "What does the designation BA 4 mean?", "a": "the BA numbering convention is literal for miniature sizes — BA 4 names a 4 mm shaft outright, bridging the gap where the coded 51xxx range does not yet begin. cage-wise BA bearings follow the standard pressed sheet-steel design: the retainer separates the miniature ball complement and is handled as one of the three loose components. The BA range covers bores 3–9 mm; from 10 mm bore upwards the standard coded range begins at 51100." }, { "q": "How is BA-4 lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 30,000 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "What do the two published speeds mean for BA-4?", "a": "The 22,000 r/min reference speed is the thermal balance under catalogue load; the 30,000 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." } ], "cross_ref": [ { "equiv_sku": "BA", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "BA-4", "BA 4" ], "locale_variants": {} }, { "sku": "BA-5", "brand": "SKF", "manufacturer_designation": "BA 5", "series": "BA-series", "type": "thrust_ball", "d_mm": 5, "D_mm": 12, "B_mm": 4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 0.852, "static_load_kN": 0.965, "fatigue_load_limit_kN": 0.036, "reference_speed_rpm": 20000, "limiting_speed_rpm": 28000, "max_rpm": 28000, "weight_g": 2, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "For a 5 mm shaft, BA 5 is the BA miniature single-direction thrust ball bearing from SKF (bore spelled out in millimetres after BA): loose shaft washer, loose housing washer and a pressed steel ball-cage set, outline 5×12×4 mm. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. BA is SKF's miniature designation: below 10 mm bore the usual two-digit code is dropped and the number after BA spells the shaft diameter in millimetres, making BA 5 a 5 mm bearing. at BA size the ball-cage assembly is a tiny stamped sheet-steel retainer delivered loose with the two washers — there is no riveted or polymer-cage variant at this scale. Envelope 5×12×4 mm (0.197×0.472×0.157 in), 3.5 mm radial section, C 0.852 kN, C0 0.965 kN, Pu 0.036 kN. reference speed 20,000 r/min (thermal) and limiting speed 28,000 r/min (mechanical), catalogue mass 2 g. Speed-ratio note for this exact unit: the reference speed is 20,000 r/min against a 28,000 r/min limiting speed, a reference-to-limit ratio of 0.71. Bore-to-OD planning: OD 12 over bore 5 is a 2.40× step for this size, and the 4 mm height gives a bore/height ratio of 1.25; use these ratios when the housing recess around the 5 mm shaft is the first constraint. At the printed limiting speed of 28,000 r/min the mean pitch diameter dm ≈ 8.5 mm implies a dn value around 238k mm·r/min; the 20,000 r/min reference speed is the thermal-planning value under catalogue load. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 5.00×10^-6 at the 28,000 r/min limiting speed raises the required axial preload to about 0.28 N; the reference-speed value 0.14 N is the thermal design point. Imperial cross-check for procurement drawings: 0.197 in bore, 0.472 in OD, 0.157 in height, and the 2 g catalogue mass converts to 0.002 kg (0.1 oz). Miniature handling note: the three BA components — shaft washer, housing washer and ball-cage assembly — are supplied loose and separate on contact, so mount the unit inside its housing recess before the shaft is offered; a dropped BA set scatters washers and balls that are nearly impossible to sort by eye, and a washer fitted reversed cannot be seen from outside once the cover is on. For reference, the 5×12 mm outline occupies less than a pencil eraser yet still publishes C0 0.965 kN; select the housing recess before the screw length, because the 4 mm stack plus cover is often the tallest feature of a miniature axial stop.", "applications": [ "appliance and office-machine thrust collars", "instrument and indexing-table pivots", "screw-jack and clamp spindles" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "permanent loss of the tiny separable components during unconfined handling or a washer fitted reversed and never detected", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 5.00×10^-6; for BA 5 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single BA 5 against two-way load lifts the loose washer off its raceway.", "When the housing seat cannot be machined square to the 5 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat BA bearing.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "There is no 51xxx coded size below 10 mm bore: the BA range is the miniature entry point for pure axial location, and at 5 mm the limit loads are small enough that shaft and housing squareness, not capacity, usually governs the design.", "Ordering discipline for BA 5: the catalogue page quotes BA 5 and its 0.852/0.965 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of BA-5?", "a": "Boundary dimensions to ISO 104: bore 5 mm, OD 12 mm, height 4 mm; weight 2 g. Load figures from SKF 17000: dynamic 0.852 kN, static 0.965 kN, fatigue limit 0.036 kN; reference speed 20,000 r/min (thermal) and limiting speed 28,000 r/min (mechanical)." }, { "q": "What does the designation BA 5 mean?", "a": "BA is SKF's miniature designation: below 10 mm bore the usual two-digit code is dropped and the number after BA spells the shaft diameter in millimetres, making BA 5 a 5 mm bearing. at BA size the ball-cage assembly is a tiny stamped sheet-steel retainer delivered loose with the two washers — there is no riveted or polymer-cage variant at this scale. The BA range covers bores 3–9 mm; from 10 mm bore upwards the standard coded range begins at 51100." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." }, { "q": "How is BA-5 lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 28,000 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "BA", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "BA-5", "BA 5" ], "locale_variants": {} }, { "sku": "BA-6", "brand": "SKF", "manufacturer_designation": "BA 6", "series": "BA-series", "type": "thrust_ball", "d_mm": 6, "D_mm": 14, "B_mm": 5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1.78, "static_load_kN": 1.92, "fatigue_load_limit_kN": 0.071, "reference_speed_rpm": 17000, "limiting_speed_rpm": 24000, "max_rpm": 24000, "weight_g": 4, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "For a 6 mm shaft, BA 6 is the BA miniature single-direction thrust ball bearing from SKF (bore spelled out in millimetres after BA): loose shaft washer, loose housing washer and a pressed steel ball-cage set, outline 6×14×5 mm. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. BA is SKF's miniature designation: below 10 mm bore the usual two-digit code is dropped and the number after BA spells the shaft diameter in millimetres, making BA 6 a 6 mm bearing. at BA size the ball-cage assembly is a tiny stamped sheet-steel retainer delivered loose with the two washers — there is no riveted or polymer-cage variant at this scale. Envelope 6×14×5 mm (0.236×0.551×0.197 in), 4.0 mm radial section, C 1.78 kN, C0 1.92 kN, Pu 0.071 kN. reference speed 17,000 r/min (thermal) and limiting speed 24,000 r/min (mechanical), catalogue mass 4 g. Selection figures for BA 6: the C0/C ratio is 1.08, Pu 0.071 kN is about 4 % of C, and the catalogue mass works out to roughly 1 g per millimetre of bore; the printed minimum-load factor is A 1.90×10^-5. Load balance: C0 1.92 kN against C 1.78 kN gives a 1.08 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 0.071 kN enters the adjusted-life check. Light-load floor: Pu = 0.071 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for BA 6; the number is 4 % of the 1.78 kN dynamic rating. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 1.90×10^-5 at the 24,000 r/min limiting speed raises the required axial preload to about 1.09 N; the reference-speed value 0.55 N is the thermal design point. Rating split for documentation: dynamic 1.78 kN (L10 life), static 1.92 kN (safety factor s0), fatigue limit 0.071 kN (adjusted life) — three different uses of three different numbers for BA 6, none interchangeable with another. Miniature handling note: the three BA components — shaft washer, housing washer and ball-cage assembly — are supplied loose and separate on contact, so mount the unit inside its housing recess before the shaft is offered; a dropped BA set scatters washers and balls that are nearly impossible to sort by eye, and a washer fitted reversed cannot be seen from outside once the cover is on. Service note at 6 mm bore: never grease-pack a BA bearing — one tiny dot of instrument oil on the ball set is enough, since the 4 g assembly will hydroplane its own cage out of position inside a flooded 14 mm OD recess.", "applications": [ "screw-jack and clamp spindles", "small vertical electric motors and fan thrust positions", "light crane hooks and swivel pins" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "permanent loss of the tiny separable components during unconfined handling or a washer fitted reversed and never detected", "false brinelling of the stationary tracks while the machine stands under vibration", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single BA 6 against two-way load lifts the loose washer off its raceway.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 1.78/1.92 kN and the available 14 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 1.78 kN track before first rotation.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 6 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "There is no 51xxx coded size below 10 mm bore: the BA range is the miniature entry point for pure axial location, and at 6 mm the limit loads are small enough that shaft and housing squareness, not capacity, usually governs the design.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for BA 6 as the miniature ba execution; other order numbers of the BA 6 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of BA-6?", "a": "Boundary dimensions to ISO 104: bore 6 mm, OD 14 mm, height 5 mm; weight 4 g. Load figures from SKF 17000: dynamic 1.78 kN, static 1.92 kN, fatigue limit 0.071 kN; reference speed 17,000 r/min (thermal) and limiting speed 24,000 r/min (mechanical)." }, { "q": "What does the designation BA 6 mean?", "a": "BA is SKF's miniature designation: below 10 mm bore the usual two-digit code is dropped and the number after BA spells the shaft diameter in millimetres, making BA 6 a 6 mm bearing. at BA size the ball-cage assembly is a tiny stamped sheet-steel retainer delivered loose with the two washers — there is no riveted or polymer-cage variant at this scale. The BA range covers bores 3–9 mm; from 10 mm bore upwards the standard coded range begins at 51100." }, { "q": "What does BA mean in BA 6?", "a": "BA marks SKF miniature thrust ball bearings for bores below 10 mm; the digits are the bore in millimetres, so BA 3 fits a 3 mm shaft. The standard coded range starts at 51100 (10 mm bore)." }, { "q": "How are BA miniature thrust bearings supplied and fitted?", "a": "As three separable components — shaft washer, housing washer and ball-cage assembly. Build the set inside the housing recess before inserting the 6 mm shaft, keep the parts in their packaging until fitting, and note the tiny C 1.78 kN rating suits instrument and light axial location duty." } ], "cross_ref": [ { "equiv_sku": "BA", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "BA-6", "BA 6" ], "locale_variants": {} }, { "sku": "BA-7", "brand": "SKF", "manufacturer_designation": "BA 7", "series": "BA-series", "type": "thrust_ball", "d_mm": 7, "D_mm": 17, "B_mm": 6, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 2.51, "static_load_kN": 2.9, "fatigue_load_limit_kN": 0.108, "reference_speed_rpm": 14000, "limiting_speed_rpm": 19000, "max_rpm": 19000, "weight_g": 6, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "BA 7 is SKF's BA-series miniature single-direction thrust ball bearing for a 7 mm shaft — the BA digits give bore in millimetres directly — supplied as a shaft washer, a housing washer and a stamped sheet-steel ball-cage assembly, 7×17×6 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. the BA prefix marks SKF miniature thrust ball bearings for shaft diameters below 10 mm — the digits give the bore in millimetres directly, so a BA 7 fits a 7 mm shaft rather than using the two-digit bore code. BA miniatures use the standard stamped sheet-steel ball-cage assembly: two pressed steel washers retain a small ball complement, and at these dimensions the cage and washers are handled as three loose parts. Envelope 7×17×6 mm (0.276×0.669×0.236 in), 5.0 mm radial section, C 2.51 kN, C0 2.9 kN, Pu 0.108 kN. reference speed 14,000 r/min (thermal) and limiting speed 19,000 r/min (mechanical), catalogue mass 6 g. Envelope economics: the 6 mm axial height over a 5.0 mm radial section yields 0.4 kN of dynamic capacity per height millimetre, and the bearing weighs 6 g for 2.51 kN C — about 2 g per rated kN. Section proportions: the 5.0 mm radial section compares with 7 mm of bore (section/bore ≈ 0.71) and the 6 mm height is 1.20× that section — the proportions that identify the BA envelope at a glance. Bore-to-OD planning: OD 17 over bore 7 is a 2.43× step for this size, and the 6 mm height gives a bore/height ratio of 1.17; use these ratios when the housing recess around the 7 mm shaft is the first constraint. Rating split for documentation: dynamic 2.51 kN (L10 life), static 2.9 kN (safety factor s0), fatigue limit 0.108 kN (adjusted life) — three different uses of three different numbers for BA 7, none interchangeable with another. Imperial cross-check for procurement drawings: 0.276 in bore, 0.669 in OD, 0.236 in height, and the 6 g catalogue mass converts to 0.006 kg (0.2 oz). Miniature handling note: the three BA components — shaft washer, housing washer and ball-cage assembly — are supplied loose and separate on contact, so mount the unit inside its housing recess before the shaft is offered; a dropped BA set scatters washers and balls that are nearly impossible to sort by eye, and a washer fitted reversed cannot be seen from outside once the cover is on. For reference, the 7×17 mm outline occupies less than a pencil eraser yet still publishes C0 2.9 kN; select the housing recess before the screw length, because the 6 mm stack plus cover is often the tallest feature of a miniature axial stop.", "applications": [ "light crane hooks and swivel pins", "screw-jack and clamp spindles", "instrument and indexing-table pivots" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "permanent loss of the tiny separable components during unconfined handling or a washer fitted reversed and never detected", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 4.40×10^-5; for BA 7 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 7 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 2.51 kN track before first rotation.", "The BA 7 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 7 mm shaft has to be carried by a radial bearing mounted alongside it.", "There is no 51xxx coded size below 10 mm bore: the BA range is the miniature entry point for pure axial location, and at 7 mm the limit loads are small enough that shaft and housing squareness, not capacity, usually governs the design.", "Ordering discipline for BA 7: the catalogue page quotes BA 7 and its 2.51/2.9 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of BA-7?", "a": "BA 7 measures 7 mm bore × 17 mm OD × 6 mm bearing height (0.276 × 0.669 × 0.236 in), mass about 6 g. SKF 17000 ratings: C 2.51 kN, C0 2.9 kN, Pu 0.108 kN, reference speed 14,000 r/min (thermal) and limiting speed 19,000 r/min (mechanical)." }, { "q": "What does the designation BA 7 mean?", "a": "the BA prefix marks SKF miniature thrust ball bearings for shaft diameters below 10 mm — the digits give the bore in millimetres directly, so a BA 7 fits a 7 mm shaft rather than using the two-digit bore code. BA miniatures use the standard stamped sheet-steel ball-cage assembly: two pressed steel washers retain a small ball complement, and at these dimensions the cage and washers are handled as three loose parts. The BA range covers bores 3–9 mm; from 10 mm bore upwards the standard coded range begins at 51100." }, { "q": "How are BA miniature thrust bearings supplied and fitted?", "a": "As three separable components — shaft washer, housing washer and ball-cage assembly. Build the set inside the housing recess before inserting the 7 mm shaft, keep the parts in their packaging until fitting, and note the tiny C 2.51 kN rating suits instrument and light axial location duty." }, { "q": "Can BA-7 carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 7 mm shaft must go to a separate radial bearing; mixed loading through BA 7 edge-loads the balls and destroys the washers." } ], "cross_ref": [ { "equiv_sku": "BA", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "BA-7", "BA 7" ], "locale_variants": {} }, { "sku": "BA-8", "brand": "SKF", "manufacturer_designation": "BA 8", "series": "BA-series", "type": "thrust_ball", "d_mm": 8, "D_mm": 19, "B_mm": 7, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 3.19, "static_load_kN": 3.8, "fatigue_load_limit_kN": 0.143, "reference_speed_rpm": 12000, "limiting_speed_rpm": 17000, "max_rpm": 17000, "weight_g": 9, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "BA 8 is SKF's BA-series miniature single-direction thrust ball bearing for a 8 mm shaft — the BA digits give bore in millimetres directly — supplied as a shaft washer, a housing washer and a stamped sheet-steel ball-cage assembly, 8×19×7 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. the BA prefix marks SKF miniature thrust ball bearings for shaft diameters below 10 mm — the digits give the bore in millimetres directly, so a BA 8 fits a 8 mm shaft rather than using the two-digit bore code. BA miniatures use the standard stamped sheet-steel ball-cage assembly: two pressed steel washers retain a small ball complement, and at these dimensions the cage and washers are handled as three loose parts. Envelope 8×19×7 mm (0.315×0.748×0.276 in), 5.5 mm radial section, C 3.19 kN, C0 3.8 kN, Pu 0.143 kN. reference speed 12,000 r/min (thermal) and limiting speed 17,000 r/min (mechanical), catalogue mass 9 g. Light-load floor: Pu = 0.143 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for BA 8; the number is 4 % of the 3.19 kN dynamic rating. Mass and section check: 9 g inside the 8×19×7 mm outline leaves a 5.5 mm radial section, and the 3.8 kN static rating is 1.19× the dynamic rating — plan static safety and minimum preload against those figures. Bore-to-OD planning: OD 19 over bore 8 is a 2.38× step for this size, and the 7 mm height gives a bore/height ratio of 1.14; use these ratios when the housing recess around the 8 mm shaft is the first constraint. Sizing arithmetic on the 8 mm bore: 3.19 kN C over the 5.5 mm radial section gives 0.6 kN per section millimetre, and the 7 mm stack height is 1.27× that section — proportions typical of a BA thrust section. Stack/annulus proportions: the 7 mm axial stack over the 233 mm² washer annulus gives 30.04 mm of height per annular square millimetre ×10⁻³, and at 9 g the bearing holds about 422.2 kN of C0 per kilogram. Miniature handling note: the three BA components — shaft washer, housing washer and ball-cage assembly — are supplied loose and separate on contact, so mount the unit inside its housing recess before the shaft is offered; a dropped BA set scatters washers and balls that are nearly impossible to sort by eye, and a washer fitted reversed cannot be seen from outside once the cover is on. For reference, the 8×19 mm outline occupies less than a pencil eraser yet still publishes C0 3.8 kN; select the housing recess before the screw length, because the 7 mm stack plus cover is often the tallest feature of a miniature axial stop.", "applications": [ "appliance and office-machine thrust collars", "screw-jack and clamp spindles", "instrument and indexing-table pivots" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "cage damage from mounting force applied through the balls instead of the washer face", "permanent loss of the tiny separable components during unconfined handling or a washer fitted reversed and never detected", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "The BA 8 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 8 mm shaft has to be carried by a radial bearing mounted alongside it.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 3.19 kN track before first rotation.", "When the housing seat cannot be machined square to the 8 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat BA bearing.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 3.19/3.8 kN and the available 19 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "There is no 51xxx coded size below 10 mm bore: the BA range is the miniature entry point for pure axial location, and at 8 mm the limit loads are small enough that shaft and housing squareness, not capacity, usually governs the design.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for BA 8 as the miniature ba execution; other order numbers of the BA 8 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of BA-8?", "a": "BA 8 measures 8 mm bore × 19 mm OD × 7 mm bearing height (0.315 × 0.748 × 0.276 in), mass about 9 g. SKF 17000 ratings: C 3.19 kN, C0 3.8 kN, Pu 0.143 kN, reference speed 12,000 r/min (thermal) and limiting speed 17,000 r/min (mechanical)." }, { "q": "What does the designation BA 8 mean?", "a": "the BA prefix marks SKF miniature thrust ball bearings for shaft diameters below 10 mm — the digits give the bore in millimetres directly, so a BA 8 fits a 8 mm shaft rather than using the two-digit bore code. BA miniatures use the standard stamped sheet-steel ball-cage assembly: two pressed steel washers retain a small ball complement, and at these dimensions the cage and washers are handled as three loose parts. The BA range covers bores 3–9 mm; from 10 mm bore upwards the standard coded range begins at 51100." }, { "q": "Can a single BA 8 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "BA", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "BA-8", "BA 8" ], "locale_variants": {} }, { "sku": "BA-9", "brand": "SKF", "manufacturer_designation": "BA 9", "series": "BA-series", "type": "thrust_ball", "d_mm": 9, "D_mm": 20, "B_mm": 7, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 3.12, "static_load_kN": 3.8, "fatigue_load_limit_kN": 0.143, "reference_speed_rpm": 12000, "limiting_speed_rpm": 16000, "max_rpm": 16000, "weight_g": 10, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "BA 9 is SKF's BA-series miniature single-direction thrust ball bearing for a 9 mm shaft — the BA digits give bore in millimetres directly — supplied as a shaft washer, a housing washer and a stamped sheet-steel ball-cage assembly, 9×20×7 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. the BA prefix marks SKF miniature thrust ball bearings for shaft diameters below 10 mm — the digits give the bore in millimetres directly, so a BA 9 fits a 9 mm shaft rather than using the two-digit bore code. BA miniatures use the standard stamped sheet-steel ball-cage assembly: two pressed steel washers retain a small ball complement, and at these dimensions the cage and washers are handled as three loose parts. Envelope 9×20×7 mm (0.354×0.787×0.276 in), 5.5 mm radial section, C 3.12 kN, C0 3.8 kN, Pu 0.143 kN. reference speed 12,000 r/min (thermal) and limiting speed 16,000 r/min (mechanical), catalogue mass 10 g. Capacity density: 3.12 kN C from 0.010 kg of bearing steel gives about 312.0 kN per kilogram; static density is correspondingly 380.0 kN/kg at C0 3.8 kN. Section proportions: the 5.5 mm radial section compares with 9 mm of bore (section/bore ≈ 0.61) and the 7 mm height is 1.27× that section — the proportions that identify the BA envelope at a glance. Speed band width for this size is 4,000 r/min between reference and limiting (1.33× ratio); lubrication, preload and heat removal decide where inside that band BA 9 can actually run. Sizing arithmetic on the 9 mm bore: 3.12 kN C over the 5.5 mm radial section gives 0.6 kN per section millimetre, and the 7 mm stack height is 1.27× that section — proportions typical of a BA thrust section. At the printed limiting speed of 16,000 r/min the mean pitch diameter dm ≈ 14.5 mm implies a dn value around 232k mm·r/min; the 12,000 r/min reference speed is the thermal-planning value under catalogue load. Miniature handling note: the three BA components — shaft washer, housing washer and ball-cage assembly — are supplied loose and separate on contact, so mount the unit inside its housing recess before the shaft is offered; a dropped BA set scatters washers and balls that are nearly impossible to sort by eye, and a washer fitted reversed cannot be seen from outside once the cover is on. Service note at 9 mm bore: never grease-pack a BA bearing — one tiny dot of instrument oil on the ball set is enough, since the 10 g assembly will hydroplane its own cage out of position inside a flooded 20 mm OD recess.", "applications": [ "instrument and indexing-table pivots", "appliance and office-machine thrust collars", "screw-jack and clamp spindles" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "permanent loss of the tiny separable components during unconfined handling or a washer fitted reversed and never detected", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 7.50×10^-5; for BA 9 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 9 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 3.12/3.8 kN and the available 20 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "There is no 51xxx coded size below 10 mm bore: the BA range is the miniature entry point for pure axial location, and at 9 mm the limit loads are small enough that shaft and housing squareness, not capacity, usually governs the design.", "The 3.12/3.8 kN figures belong to BA 9 specifically (the miniature ba execution of BA 9); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of BA-9?", "a": "BA 9 measures 9 mm bore × 20 mm OD × 7 mm bearing height (0.354 × 0.787 × 0.276 in), mass about 10 g. SKF 17000 ratings: C 3.12 kN, C0 3.8 kN, Pu 0.143 kN, reference speed 12,000 r/min (thermal) and limiting speed 16,000 r/min (mechanical)." }, { "q": "What does the designation BA 9 mean?", "a": "the BA prefix marks SKF miniature thrust ball bearings for shaft diameters below 10 mm — the digits give the bore in millimetres directly, so a BA 9 fits a 9 mm shaft rather than using the two-digit bore code. BA miniatures use the standard stamped sheet-steel ball-cage assembly: two pressed steel washers retain a small ball complement, and at these dimensions the cage and washers are handled as three loose parts. The BA range covers bores 3–9 mm; from 10 mm bore upwards the standard coded range begins at 51100." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." }, { "q": "How is BA-9 lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 16,000 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "BA", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "BA-9", "BA 9" ], "locale_variants": {} }, { "sku": "51100-SKF", "brand": "SKF", "manufacturer_designation": "51100", "series": "51100-series", "type": "thrust_ball", "d_mm": 10, "D_mm": 24, "B_mm": 9, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 9.95, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.56, "reference_speed_rpm": 9500, "limiting_speed_rpm": 13000, "max_rpm": 13000, "weight_g": 20, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51100 is an ISO 104 single-direction thrust ball bearing, 10 mm bore and 24 mm OD on a flat housing seat, standing 9 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 00: bore 10 mm for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 10×24×9 mm (0.394×0.945×0.354 in), 7.0 mm radial section, C 9.95 kN, C0 15.3 kN, Pu 0.56 kN. reference speed 9,500 r/min (thermal) and limiting speed 13,000 r/min (mechanical), catalogue mass 20 g. Minimum-load arithmetic: with dm ≈ 17.0 mm and factor A 0.0012, Fam ≈ A·(n·dm/1000)² at the 9,500 r/min reference speed is about 31 N for 51100; below that preload the balls skid and smear the tracks. Speed-ratio note for this exact unit: the reference speed is 9,500 r/min against a 13,000 r/min limiting speed, a reference-to-limit ratio of 0.73. Stack/annulus proportions: the 9 mm axial stack over the 374 mm² washer annulus gives 24.06 mm of height per annular square millimetre ×10⁻³, and at 20 g the bearing holds about 765.0 kN of C0 per kilogram. Speed band width for this size is 3,500 r/min between reference and limiting (1.37× ratio); lubrication, preload and heat removal decide where inside that band 51100 can actually run. Imperial cross-check for procurement drawings: 0.394 in bore, 0.945 in OD, 0.354 in height, and the 20 g catalogue mass converts to 0.020 kg (0.7 oz). Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 9 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 9.95 kN C.", "applications": [ "light crane hooks and swivel pins", "appliance and office-machine thrust collars", "small vertical electric motors and fan thrust positions" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.0012; for 51100 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 9.95 kN track before first rotation.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51100 against two-way load lifts the loose washer off its raceway.", "When the housing seat cannot be machined square to the 10 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "Ordering discipline for 51100: the catalogue page quotes 51100 and its 9.95/15.3 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51100-SKF?", "a": "The catalogue envelope is 10×24×9 mm, mass 20 g; ratings C 9.95 kN / C0 15.3 kN / Pu 0.56 kN, reference speed 9,500 r/min (thermal) and limiting speed 13,000 r/min (mechanical)." }, { "q": "What does the designation 51100 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 00: bore 10 mm for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51100-SKF?", "a": "The 9,500 r/min reference speed is the thermal balance under catalogue load; the 13,000 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51100-SKF need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.0012 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51100", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51100-SKF", "51100" ], "locale_variants": {} }, { "sku": "51200-SKF", "brand": "SKF", "manufacturer_designation": "51200", "series": "51200-series", "type": "thrust_ball", "d_mm": 10, "D_mm": 26, "B_mm": 11, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 18.6, "fatigue_load_limit_kN": 0.695, "reference_speed_rpm": 8000, "limiting_speed_rpm": 11000, "max_rpm": 11000, "weight_g": 30, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51200 series order number 51200 is a SKF single-direction thrust ball bearing for a 10 mm seat, built to ISO 104, with a flat housing seating surface, 10×26×11 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 00 decodes to 10 mm under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 10×26×11 mm (0.394×1.024×0.433 in), 8.0 mm radial section, C 12.7 kN, C0 18.6 kN, Pu 0.695 kN. reference speed 8,000 r/min (thermal) and limiting speed 11,000 r/min (mechanical), catalogue mass 30 g. Light-load floor: Pu = 0.695 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51200; the number is 5 % of the 12.7 kN dynamic rating. Sizing arithmetic on the 10 mm bore: 12.7 kN C over the 8.0 mm radial section gives 1.6 kN per section millimetre, and the 11 mm stack height is 1.38× that section — proportions typical of a 51200 thrust section. Speed-ratio note for this exact unit: the reference speed is 8,000 r/min against a 11,000 r/min limiting speed, a reference-to-limit ratio of 0.73. Mass and section check: 30 g inside the 10×26×11 mm outline leaves a 8.0 mm radial section, and the 18.6 kN static rating is 1.46× the dynamic rating — plan static safety and minimum preload against those figures. Minimum-load arithmetic: with dm ≈ 18.0 mm and factor A 0.0018, Fam ≈ A·(n·dm/1000)² at the 8,000 r/min reference speed is about 37 N for 51200; below that preload the balls skid and smear the tracks. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 10 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 12.7/18.6 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "appliance and office-machine thrust collars", "screw-jack and clamp spindles", "instrument and indexing-table pivots" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "cage damage from mounting force applied through the balls instead of the washer face", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "When the housing seat cannot be machined square to the 10 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.0018; for 51200 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 12.7/18.6 kN and the available 26 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The 51200 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 10 mm shaft has to be carried by a radial bearing mounted alongside it.", "Ordering discipline for 51200: the catalogue page quotes 51200 and its 12.7/18.6 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51200-SKF?", "a": "Boundary dimensions to ISO 104: bore 10 mm, OD 26 mm, height 11 mm; weight 30 g. Load figures from SKF 17000: dynamic 12.7 kN, static 18.6 kN, fatigue limit 0.695 kN; reference speed 8,000 r/min (thermal) and limiting speed 11,000 r/min (mechanical)." }, { "q": "What does the designation 51200 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 00 decodes to 10 mm under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51200-SKF lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 11,000 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 10 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51200", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51200-SKF", "51200" ], "locale_variants": {} }, { "sku": "51101-SKF", "brand": "SKF", "manufacturer_designation": "51101", "series": "51100-series", "type": "thrust_ball", "d_mm": 12, "D_mm": 26, "B_mm": 9, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 10.4, "static_load_kN": 16.6, "fatigue_load_limit_kN": 0.62, "reference_speed_rpm": 9000, "limiting_speed_rpm": 13000, "max_rpm": 13000, "weight_g": 22, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51101 is SKF's 12 mm-bore single-direction thrust ball bearing in the 51100 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 12×26×9 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 01 encode the bore as 12 mm, the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 12×26×9 mm (0.472×1.024×0.354 in), 7.0 mm radial section, C 10.4 kN, C0 16.6 kN, Pu 0.62 kN. reference speed 9,000 r/min (thermal) and limiting speed 13,000 r/min (mechanical), catalogue mass 22 g. Mass and section check: 22 g inside the 12×26×9 mm outline leaves a 7.0 mm radial section, and the 16.6 kN static rating is 1.60× the dynamic rating — plan static safety and minimum preload against those figures. Stack/annulus proportions: the 9 mm axial stack over the 418 mm² washer annulus gives 21.53 mm of height per annular square millimetre ×10⁻³, and at 22 g the bearing holds about 754.5 kN of C0 per kilogram. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 13,000 r/min while thermal balance under catalogue load sets the 9,000 r/min reference; at dm ≈ 19.0 mm the corresponding dn is approximately 247k mm·r/min. Speed band width for this size is 4,000 r/min between reference and limiting (1.44× ratio); lubrication, preload and heat removal decide where inside that band 51101 can actually run. Light-load floor: Pu = 0.62 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51101; the number is 6 % of the 10.4 kN dynamic rating. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 12 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 10.4/16.6 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "small vertical electric motors and fan thrust positions", "light crane hooks and swivel pins", "appliance and office-machine thrust collars" ], "failure_modes": [ "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "false brinelling of the stationary tracks while the machine stands under vibration", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.0014; for 51101 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 9 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 10.4 kN track before first rotation.", "Ordering discipline for 51101: the catalogue page quotes 51101 and its 10.4/16.6 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51101-SKF?", "a": "51101 measures 12 mm bore × 26 mm OD × 9 mm bearing height (0.472 × 1.024 × 0.354 in), mass about 22 g. SKF 17000 ratings: C 10.4 kN, C0 16.6 kN, Pu 0.62 kN, reference speed 9,000 r/min (thermal) and limiting speed 13,000 r/min (mechanical)." }, { "q": "What does the designation 51101 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 01 encode the bore as 12 mm, the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can a single 51101 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." }, { "q": "What do the two published speeds mean for 51101-SKF?", "a": "The 9,000 r/min reference speed is the thermal balance under catalogue load; the 13,000 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." } ], "cross_ref": [ { "equiv_sku": "51101", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51101-SKF", "51101" ], "locale_variants": {} }, { "sku": "51201-SKF", "brand": "SKF", "manufacturer_designation": "51201", "series": "51200-series", "type": "thrust_ball", "d_mm": 12, "D_mm": 28, "B_mm": 11, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 13.3, "static_load_kN": 20.8, "fatigue_load_limit_kN": 0.765, "reference_speed_rpm": 8000, "limiting_speed_rpm": 11000, "max_rpm": 11000, "weight_g": 34, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51201 is SKF's 12 mm-bore single-direction thrust ball bearing in the 51200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 12×28×11 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 01 encode the bore as 12 mm, the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 12×28×11 mm (0.472×1.102×0.433 in), 8.0 mm radial section, C 13.3 kN, C0 20.8 kN, Pu 0.765 kN. reference speed 8,000 r/min (thermal) and limiting speed 11,000 r/min (mechanical), catalogue mass 34 g. Minimum-load arithmetic: with dm ≈ 20.0 mm and factor A 0.0022, Fam ≈ A·(n·dm/1000)² at the 8,000 r/min reference speed is about 56 N for 51201; below that preload the balls skid and smear the tracks. Bore-to-OD planning: OD 28 over bore 12 is a 2.33× step for this size, and the 11 mm height gives a bore/height ratio of 1.09; use these ratios when the housing recess around the 12 mm shaft is the first constraint. Pitch-diameter arithmetic: dm = (12+28)/2 = 20.0 mm; at the 11,000 r/min limiting speed that corresponds to roughly 220k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Rating split for documentation: dynamic 13.3 kN (L10 life), static 20.8 kN (safety factor s0), fatigue limit 0.765 kN (adjusted life) — three different uses of three different numbers for 51201, none interchangeable with another. Envelope economics: the 11 mm axial height over a 8.0 mm radial section yields 1.2 kN of dynamic capacity per height millimetre, and the bearing weighs 34 g for 13.3 kN C — about 3 g per rated kN. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 11 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 13.3 kN C.", "applications": [ "appliance and office-machine thrust collars", "light crane hooks and swivel pins", "instrument and indexing-table pivots" ], "failure_modes": [ "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51201 against two-way load lifts the loose washer off its raceway.", "When the housing seat cannot be machined square to the 12 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 12 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51201 as the single flat pressed steel execution; other order numbers of the 51201 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51201-SKF?", "a": "51201 measures 12 mm bore × 28 mm OD × 11 mm bearing height (0.472 × 1.102 × 0.433 in), mass about 34 g. SKF 17000 ratings: C 13.3 kN, C0 20.8 kN, Pu 0.765 kN, reference speed 8,000 r/min (thermal) and limiting speed 11,000 r/min (mechanical)." }, { "q": "What does the designation 51201 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 01 encode the bore as 12 mm, the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 12 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51201 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51201", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "53201", "equiv_brand": "SKF", "level": "full", "note": "Same 12×28×11 mm ISO 104 thrust-ball envelope with catalogue ratings within 10 %; 53201 is the single-direction, sphered housing washer with U 201 seat washer, stamped sheet-steel cage execution of this size — boundary dimensions interchangeable, execution differs. The counterpart is a sphered execution that needs its U 201 seat washer; its mounted H1 is taller than the bearing height." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51201-SKF", "51201" ], "locale_variants": {} }, { "sku": "51102-SKF", "brand": "SKF", "manufacturer_designation": "51102", "series": "51100-series", "type": "thrust_ball", "d_mm": 15, "D_mm": 28, "B_mm": 9, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 10.6, "static_load_kN": 18.3, "fatigue_load_limit_kN": 0.67, "reference_speed_rpm": 8500, "limiting_speed_rpm": 12000, "max_rpm": 12000, "weight_g": 23, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51102 is an ISO 104 single-direction thrust ball bearing, 15 mm bore and 28 mm OD on a flat housing seat, standing 9 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 02: bore 15 mm for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 15×28×9 mm (0.591×1.102×0.354 in), 6.5 mm radial section, C 10.6 kN, C0 18.3 kN, Pu 0.67 kN. reference speed 8,500 r/min (thermal) and limiting speed 12,000 r/min (mechanical), catalogue mass 23 g. Selection figures for 51102: the C0/C ratio is 1.73, Pu 0.67 kN is about 6 % of C, and the catalogue mass works out to roughly 2 g per millimetre of bore; the printed minimum-load factor is A 0.0017. Envelope economics: the 9 mm axial height over a 6.5 mm radial section yields 1.2 kN of dynamic capacity per height millimetre, and the bearing weighs 23 g for 10.6 kN C — about 2 g per rated kN. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51102 covers about 439 mm², distributing C0 18.3 kN over a mean track circle of π·dm ≈ 68 mm. Load balance: C0 18.3 kN against C 10.6 kN gives a 1.73 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 0.67 kN enters the adjusted-life check. Section proportions: the 6.5 mm radial section compares with 15 mm of bore (section/bore ≈ 0.43) and the 9 mm height is 1.38× that section — the proportions that identify the 51100 envelope at a glance. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 15 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 10.6/18.3 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "light crane hooks and swivel pins", "instrument and indexing-table pivots", "small vertical electric motors and fan thrust positions" ], "failure_modes": [ "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "pitting on one track sector from a perpetually eccentric thrust line", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 15 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51102 against two-way load lifts the loose washer off its raceway.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.0017; for 51102 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The 10.6/18.3 kN figures belong to 51102 specifically (the single flat pressed steel execution of 51102); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51102-SKF?", "a": "The catalogue envelope is 15×28×9 mm, mass 23 g; ratings C 10.6 kN / C0 18.3 kN / Pu 0.67 kN, reference speed 8,500 r/min (thermal) and limiting speed 12,000 r/min (mechanical)." }, { "q": "What does the designation 51102 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 02: bore 15 mm for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 15 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51102 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51102", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51102-SKF", "51102" ], "locale_variants": {} }, { "sku": "51202-SKF", "brand": "SKF", "manufacturer_designation": "51202", "series": "51200-series", "type": "thrust_ball", "d_mm": 15, "D_mm": 32, "B_mm": 12, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 15.9, "static_load_kN": 25, "fatigue_load_limit_kN": 0.915, "reference_speed_rpm": 7000, "limiting_speed_rpm": 10000, "max_rpm": 10000, "weight_g": 46, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51200 series order number 51202 is a SKF single-direction thrust ball bearing for a 15 mm seat, built to ISO 104, with a flat housing seating surface, 15×32×12 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 02 decodes to 15 mm under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 15×32×12 mm (0.591×1.26×0.472 in), 8.5 mm radial section, C 15.9 kN, C0 25 kN, Pu 0.915 kN. reference speed 7,000 r/min (thermal) and limiting speed 10,000 r/min (mechanical), catalogue mass 46 g. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 10,000 r/min while thermal balance under catalogue load sets the 7,000 r/min reference; at dm ≈ 23.5 mm the corresponding dn is approximately 235k mm·r/min. Minimum-load arithmetic: with dm ≈ 23.5 mm and factor A 0.0038, Fam ≈ A·(n·dm/1000)² at the 7,000 r/min reference speed is about 103 N for 51202; below that preload the balls skid and smear the tracks. Speed band width for this size is 3,000 r/min between reference and limiting (1.43× ratio); lubrication, preload and heat removal decide where inside that band 51202 can actually run. Load balance: C0 25 kN against C 15.9 kN gives a 1.57 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 0.915 kN enters the adjusted-life check. Stack/annulus proportions: the 12 mm axial stack over the 628 mm² washer annulus gives 19.11 mm of height per annular square millimetre ×10⁻³, and at 46 g the bearing holds about 543.5 kN of C0 per kilogram. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 12 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 15.9 kN C.", "applications": [ "screw-jack and clamp spindles", "instrument and indexing-table pivots", "light crane hooks and swivel pins" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "washer face scoring from swarf trapped between the loose housing washer and its register", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 15 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "When the housing seat cannot be machined square to the 15 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.0038; for 51202 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The 15.9/25 kN figures belong to 51202 specifically (the single flat pressed steel execution of 51202); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51202-SKF?", "a": "Boundary dimensions to ISO 104: bore 15 mm, OD 32 mm, height 12 mm; weight 46 g. Load figures from SKF 17000: dynamic 15.9 kN, static 25 kN, fatigue limit 0.915 kN; reference speed 7,000 r/min (thermal) and limiting speed 10,000 r/min (mechanical)." }, { "q": "What does the designation 51202 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 02 decodes to 15 mm under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can a single 51202 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." }, { "q": "What do the two published speeds mean for 51202-SKF?", "a": "The 7,000 r/min reference speed is the thermal balance under catalogue load; the 10,000 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." } ], "cross_ref": [ { "equiv_sku": "51202", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51202-SKF", "51202" ], "locale_variants": {} }, { "sku": "51103-SKF", "brand": "SKF", "manufacturer_designation": "51103", "series": "51100-series", "type": "thrust_ball", "d_mm": 17, "D_mm": 30, "B_mm": 9, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 11.4, "static_load_kN": 21.2, "fatigue_load_limit_kN": 0.78, "reference_speed_rpm": 8500, "limiting_speed_rpm": 12000, "max_rpm": 12000, "weight_g": 25, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51103 is a SKF single-direction thrust ball bearing for a 17 mm seat, built to ISO 104, with a flat housing seating surface, 17×30×9 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 03 decodes to 17 mm under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 17×30×9 mm (0.669×1.181×0.354 in), 6.5 mm radial section, C 11.4 kN, C0 21.2 kN, Pu 0.78 kN. reference speed 8,500 r/min (thermal) and limiting speed 12,000 r/min (mechanical), catalogue mass 25 g. Section proportions: the 6.5 mm radial section compares with 17 mm of bore (section/bore ≈ 0.38) and the 9 mm height is 1.38× that section — the proportions that identify the 51100 envelope at a glance. Pitch-diameter arithmetic: dm = (17+30)/2 = 23.5 mm; at the 12,000 r/min limiting speed that corresponds to roughly 282k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Speed band width for this size is 3,500 r/min between reference and limiting (1.41× ratio); lubrication, preload and heat removal decide where inside that band 51103 can actually run. Rating split for documentation: dynamic 11.4 kN (L10 life), static 21.2 kN (safety factor s0), fatigue limit 0.78 kN (adjusted life) — three different uses of three different numbers for 51103, none interchangeable with another. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51103 covers about 480 mm², distributing C0 21.2 kN over a mean track circle of π·dm ≈ 74 mm. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 9 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 11.4 kN C.", "applications": [ "screw-jack and clamp spindles", "light crane hooks and swivel pins", "instrument and indexing-table pivots" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 17 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 11.4/21.2 kN and the available 30 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "When the housing seat cannot be machined square to the 17 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 9 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The 11.4/21.2 kN figures belong to 51103 specifically (the single flat pressed steel execution of 51103); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51103-SKF?", "a": "Boundary dimensions to ISO 104: bore 17 mm, OD 30 mm, height 9 mm; weight 25 g. Load figures from SKF 17000: dynamic 11.4 kN, static 21.2 kN, fatigue limit 0.78 kN; reference speed 8,500 r/min (thermal) and limiting speed 12,000 r/min (mechanical)." }, { "q": "What does the designation 51103 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 03 decodes to 17 mm under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51103-SKF lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 12,000 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 17 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51103", "equiv_brand": "NTN", "level": "partial", "note": "Same 17×30×9 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51103-SKF", "51103" ], "locale_variants": {} }, { "sku": "51203-SKF", "brand": "SKF", "manufacturer_designation": "51203", "series": "51200-series", "type": "thrust_ball", "d_mm": 17, "D_mm": 35, "B_mm": 12, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 16.3, "static_load_kN": 27, "fatigue_load_limit_kN": 1, "reference_speed_rpm": 6700, "limiting_speed_rpm": 9500, "max_rpm": 9500, "weight_g": 53, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51203 is an ISO 104 single-direction thrust ball bearing, 17 mm bore and 35 mm OD on a flat housing seat, standing 12 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 03: bore 17 mm for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 17×35×12 mm (0.669×1.378×0.472 in), 9.0 mm radial section, C 16.3 kN, C0 27 kN, Pu 1 kN. reference speed 6,700 r/min (thermal) and limiting speed 9,500 r/min (mechanical), catalogue mass 53 g. Bore-to-OD planning: OD 35 over bore 17 is a 2.06× step for this size, and the 12 mm height gives a bore/height ratio of 1.42; use these ratios when the housing recess around the 17 mm shaft is the first constraint. At the printed limiting speed of 9,500 r/min the mean pitch diameter dm ≈ 26.0 mm implies a dn value around 247k mm·r/min; the 6,700 r/min reference speed is the thermal-planning value under catalogue load. Envelope economics: the 12 mm axial height over a 9.0 mm radial section yields 1.4 kN of dynamic capacity per height millimetre, and the bearing weighs 53 g for 16.3 kN C — about 3 g per rated kN. Speed band width for this size is 2,800 r/min between reference and limiting (1.42× ratio); lubrication, preload and heat removal decide where inside that band 51203 can actually run. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51203 covers about 735 mm², distributing C0 27 kN over a mean track circle of π·dm ≈ 82 mm. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 17 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 16.3/27 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "light crane hooks and swivel pins", "screw-jack and clamp spindles", "small vertical electric motors and fan thrust positions" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51203 against two-way load lifts the loose washer off its raceway.", "When the housing seat cannot be machined square to the 17 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "The 51203 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 17 mm shaft has to be carried by a radial bearing mounted alongside it.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 17 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51203 as the single flat pressed steel execution; other order numbers of the 51203 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51203-SKF?", "a": "The catalogue envelope is 17×35×12 mm, mass 53 g; ratings C 16.3 kN / C0 27 kN / Pu 1 kN, reference speed 6,700 r/min (thermal) and limiting speed 9,500 r/min (mechanical)." }, { "q": "What does the designation 51203 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 03: bore 17 mm for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51203-SKF?", "a": "The 6,700 r/min reference speed is the thermal balance under catalogue load; the 9,500 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51203-SKF need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.0047 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51203", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51203-SKF", "51203" ], "locale_variants": {} }, { "sku": "51104-SKF", "brand": "SKF", "manufacturer_designation": "51104", "series": "51100-series", "type": "thrust_ball", "d_mm": 20, "D_mm": 35, "B_mm": 10, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 15.1, "static_load_kN": 29, "fatigue_load_limit_kN": 1.08, "reference_speed_rpm": 7500, "limiting_speed_rpm": 10000, "max_rpm": 10000, "weight_g": 37, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51104 is an ISO 104 single-direction thrust ball bearing, 20 mm bore and 35 mm OD on a flat housing seat, standing 10 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 04: bore 20 mm (code 04 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 20×35×10 mm (0.787×1.378×0.394 in), 7.5 mm radial section, C 15.1 kN, C0 29 kN, Pu 1.08 kN. reference speed 7,500 r/min (thermal) and limiting speed 10,000 r/min (mechanical), catalogue mass 37 g. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 10,000 r/min while thermal balance under catalogue load sets the 7,500 r/min reference; at dm ≈ 27.5 mm the corresponding dn is approximately 275k mm·r/min. Section proportions: the 7.5 mm radial section compares with 20 mm of bore (section/bore ≈ 0.38) and the 10 mm height is 1.33× that section — the proportions that identify the 51100 envelope at a glance. Envelope economics: the 10 mm axial height over a 7.5 mm radial section yields 1.5 kN of dynamic capacity per height millimetre, and the bearing weighs 37 g for 15.1 kN C — about 2 g per rated kN. Light-load floor: Pu = 1.08 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51104; the number is 7 % of the 15.1 kN dynamic rating. Static-first selection data: 29 kN C0 spread across the 10 mm stack gives 2.9 kN of static rating per height millimetre, and the 37 g mass/C0 ratio is about 1 g per static kN — crane-hook and screw positions are normally sized on these two figures. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 20 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 15.1/29 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "screw-jack and clamp spindles", "small vertical electric motors and fan thrust positions", "light crane hooks and swivel pins" ], "failure_modes": [ "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 15.1 kN track before first rotation.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 10 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51104 against two-way load lifts the loose washer off its raceway.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 15.1/29 kN and the available 35 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The 15.1/29 kN figures belong to 51104 specifically (the single flat pressed steel execution of 51104); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51104-SKF?", "a": "The catalogue envelope is 20×35×10 mm, mass 37 g; ratings C 15.1 kN / C0 29 kN / Pu 1.08 kN, reference speed 7,500 r/min (thermal) and limiting speed 10,000 r/min (mechanical)." }, { "q": "What does the designation 51104 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 04: bore 20 mm (code 04 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." }, { "q": "How is 51104-SKF lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 10,000 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "51104", "equiv_brand": "NTN", "level": "partial", "note": "Same 20×35×10 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51104-SKF", "51104" ], "locale_variants": {} }, { "sku": "51204-SKF", "brand": "SKF", "manufacturer_designation": "51204", "series": "51200-series", "type": "thrust_ball", "d_mm": 20, "D_mm": 40, "B_mm": 14, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 21.2, "static_load_kN": 37.5, "fatigue_load_limit_kN": 1.4, "reference_speed_rpm": 6000, "limiting_speed_rpm": 8000, "max_rpm": 8000, "weight_g": 83, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51200 series order number 51204 is a SKF single-direction thrust ball bearing for a 20 mm seat, built to ISO 104, with a flat housing seating surface, 20×40×14 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 04 decodes to 20 mm (code 04 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 20×40×14 mm (0.787×1.575×0.551 in), 10.0 mm radial section, C 21.2 kN, C0 37.5 kN, Pu 1.4 kN. reference speed 6,000 r/min (thermal) and limiting speed 8,000 r/min (mechanical), catalogue mass 83 g. Mass and section check: 83 g inside the 20×40×14 mm outline leaves a 10.0 mm radial section, and the 37.5 kN static rating is 1.77× the dynamic rating — plan static safety and minimum preload against those figures. Speed band width for this size is 2,000 r/min between reference and limiting (1.33× ratio); lubrication, preload and heat removal decide where inside that band 51204 can actually run. At the printed limiting speed of 8,000 r/min the mean pitch diameter dm ≈ 30.0 mm implies a dn value around 240k mm·r/min; the 6,000 r/min reference speed is the thermal-planning value under catalogue load. Stack/annulus proportions: the 14 mm axial stack over the 942 mm² washer annulus gives 14.86 mm of height per annular square millimetre ×10⁻³, and at 83 g the bearing holds about 451.8 kN of C0 per kilogram. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 8,000 r/min while thermal balance under catalogue load sets the 6,000 r/min reference; at dm ≈ 30.0 mm the corresponding dn is approximately 240k mm·r/min. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 20 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 21.2/37.5 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "small vertical electric motors and fan thrust positions", "instrument and indexing-table pivots", "screw-jack and clamp spindles" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "washer face scoring from swarf trapped between the loose housing washer and its register", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "When the housing seat cannot be machined square to the 20 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.0085; for 51204 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 21.2/37.5 kN and the available 40 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The 51204 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 20 mm shaft has to be carried by a radial bearing mounted alongside it.", "Ordering discipline for 51204: the catalogue page quotes 51204 and its 21.2/37.5 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51204-SKF?", "a": "Boundary dimensions to ISO 104: bore 20 mm, OD 40 mm, height 14 mm; weight 83 g. Load figures from SKF 17000: dynamic 21.2 kN, static 37.5 kN, fatigue limit 1.4 kN; reference speed 6,000 r/min (thermal) and limiting speed 8,000 r/min (mechanical)." }, { "q": "What does the designation 51204 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 04 decodes to 20 mm (code 04 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51204-SKF need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.0085 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51204", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51204-SKF", "51204" ], "locale_variants": {} }, { "sku": "51105-SKF", "brand": "SKF", "manufacturer_designation": "51105", "series": "51100-series", "type": "thrust_ball", "d_mm": 25, "D_mm": 42, "B_mm": 11, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 18.2, "static_load_kN": 39, "fatigue_load_limit_kN": 1.43, "reference_speed_rpm": 6300, "limiting_speed_rpm": 9000, "max_rpm": 9000, "weight_g": 56, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51105 is a SKF single-direction thrust ball bearing for a 25 mm seat, built to ISO 104, with a flat housing seating surface, 25×42×11 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 05 decodes to 25 mm (code 05 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 25×42×11 mm (0.984×1.654×0.433 in), 8.5 mm radial section, C 18.2 kN, C0 39 kN, Pu 1.43 kN. reference speed 6,300 r/min (thermal) and limiting speed 9,000 r/min (mechanical), catalogue mass 56 g. Mass and section check: 56 g inside the 25×42×11 mm outline leaves a 8.5 mm radial section, and the 39 kN static rating is 2.14× the dynamic rating — plan static safety and minimum preload against those figures. Light-load floor: Pu = 1.43 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51105; the number is 8 % of the 18.2 kN dynamic rating. Imperial cross-check for procurement drawings: 0.984 in bore, 1.654 in OD, 0.433 in height, and the 56 g catalogue mass converts to 0.056 kg (2.0 oz). Load balance: C0 39 kN against C 18.2 kN gives a 2.14 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 1.43 kN enters the adjusted-life check. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.0079 at the 9,000 r/min limiting speed raises the required axial preload to about 718 N; the reference-speed value 352 N is the thermal design point. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 25 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 18.2/39 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "vertical pump and motor shaft thrust", "crane hooks and lifting-block pins", "machine-tool adjustment screws and tailstock centres" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "false brinelling of the stationary tracks while the machine stands under vibration", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 18.2 kN track before first rotation.", "When the housing seat cannot be machined square to the 25 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 18.2/39 kN and the available 42 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51105 against two-way load lifts the loose washer off its raceway.", "The 18.2/39 kN figures belong to 51105 specifically (the single flat pressed steel execution of 51105); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51105-SKF?", "a": "Boundary dimensions to ISO 104: bore 25 mm, OD 42 mm, height 11 mm; weight 56 g. Load figures from SKF 17000: dynamic 18.2 kN, static 39 kN, fatigue limit 1.43 kN; reference speed 6,300 r/min (thermal) and limiting speed 9,000 r/min (mechanical)." }, { "q": "What does the designation 51105 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 05 decodes to 25 mm (code 05 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can 51105-SKF carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 25 mm shaft must go to a separate radial bearing; mixed loading through 51105 edge-loads the balls and destroys the washers." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." } ], "cross_ref": [ { "equiv_sku": "51105", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51105-SKF", "51105" ], "locale_variants": {} }, { "sku": "51205-SKF", "brand": "SKF", "manufacturer_designation": "51205", "series": "51200-series", "type": "thrust_ball", "d_mm": 25, "D_mm": 47, "B_mm": 15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 26.5, "static_load_kN": 50, "fatigue_load_limit_kN": 1.86, "reference_speed_rpm": 5300, "limiting_speed_rpm": 7500, "max_rpm": 7500, "weight_g": 110, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51205 is an ISO 104 single-direction thrust ball bearing, 25 mm bore and 47 mm OD on a flat housing seat, standing 15 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 05: bore 25 mm (code 05 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 25×47×15 mm (0.984×1.85×0.591 in), 11.0 mm radial section, C 26.5 kN, C0 50 kN, Pu 1.86 kN. reference speed 5,300 r/min (thermal) and limiting speed 7,500 r/min (mechanical), catalogue mass 110 g. Speed band width for this size is 2,200 r/min between reference and limiting (1.42× ratio); lubrication, preload and heat removal decide where inside that band 51205 can actually run. Section proportions: the 11.0 mm radial section compares with 25 mm of bore (section/bore ≈ 0.44) and the 15 mm height is 1.36× that section — the proportions that identify the 51200 envelope at a glance. Stack/annulus proportions: the 15 mm axial stack over the 1,244 mm² washer annulus gives 12.06 mm of height per annular square millimetre ×10⁻³, and at 110 g the bearing holds about 454.5 kN of C0 per kilogram. Load balance: C0 50 kN against C 26.5 kN gives a 1.89 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 1.86 kN enters the adjusted-life check. At the printed limiting speed of 7,500 r/min the mean pitch diameter dm ≈ 36.0 mm implies a dn value around 270k mm·r/min; the 5,300 r/min reference speed is the thermal-planning value under catalogue load. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 15 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 26.5 kN C.", "applications": [ "machine-tool adjustment screws and tailstock centres", "screw jacks and press-adjustment spindles", "vertical pump and motor shaft thrust" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "pitting on one track sector from a perpetually eccentric thrust line", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 26.5 kN track before first rotation.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.015; for 51205 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The 51205 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 25 mm shaft has to be carried by a radial bearing mounted alongside it.", "When the housing seat cannot be machined square to the 25 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "The 26.5/50 kN figures belong to 51205 specifically (the single flat pressed steel execution of 51205); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51205-SKF?", "a": "The catalogue envelope is 25×47×15 mm, mass 110 g; ratings C 26.5 kN / C0 50 kN / Pu 1.86 kN, reference speed 5,300 r/min (thermal) and limiting speed 7,500 r/min (mechanical)." }, { "q": "What does the designation 51205 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 05: bore 25 mm (code 05 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." }, { "q": "Can 51205-SKF carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 25 mm shaft must go to a separate radial bearing; mixed loading through 51205 edge-loads the balls and destroys the washers." } ], "cross_ref": [ { "equiv_sku": "51205", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51205-SKF", "51205" ], "locale_variants": {} }, { "sku": "51305-SKF", "brand": "SKF", "manufacturer_designation": "51305", "series": "51300-series", "type": "thrust_ball", "d_mm": 25, "D_mm": 52, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 34.5, "static_load_kN": 60, "fatigue_load_limit_kN": 2.24, "reference_speed_rpm": 4500, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 170, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51305 is an ISO 104 single-direction thrust ball bearing, 25 mm bore and 52 mm OD on a flat housing seat, standing 18 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 05: bore 25 mm (code 05 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 25×52×18 mm (0.984×2.047×0.709 in), 13.5 mm radial section, C 34.5 kN, C0 60 kN, Pu 2.24 kN. reference speed 4,500 r/min (thermal) and limiting speed 6,300 r/min (mechanical), catalogue mass 170 g. Bore-to-OD planning: OD 52 over bore 25 is a 2.08× step for this size, and the 18 mm height gives a bore/height ratio of 1.39; use these ratios when the housing recess around the 25 mm shaft is the first constraint. Light-load floor: Pu = 2.24 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51305; the number is 6 % of the 34.5 kN dynamic rating. Mass and section check: 170 g inside the 25×52×18 mm outline leaves a 13.5 mm radial section, and the 60 kN static rating is 1.74× the dynamic rating — plan static safety and minimum preload against those figures. Speed band width for this size is 1,800 r/min between reference and limiting (1.40× ratio); lubrication, preload and heat removal decide where inside that band 51305 can actually run. Minimum-load arithmetic: with dm ≈ 38.5 mm and factor A 0.018, Fam ≈ A·(n·dm/1000)² at the 4,500 r/min reference speed is about 540 N for 51305; below that preload the balls skid and smear the tracks. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 18 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 34.5 kN C.", "applications": [ "low-speed reducer thrust positions", "screw jacks and press-adjustment spindles", "machine-tool adjustment screws and tailstock centres" ], "failure_modes": [ "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "washer face scoring from swarf trapped between the loose housing washer and its register", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 34.5/60 kN and the available 52 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.018; for 51305 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51305 against two-way load lifts the loose washer off its raceway.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 18 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Ordering discipline for 51305: the catalogue page quotes 51305 and its 34.5/60 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51305-SKF?", "a": "The catalogue envelope is 25×52×18 mm, mass 170 g; ratings C 34.5 kN / C0 60 kN / Pu 2.24 kN, reference speed 4,500 r/min (thermal) and limiting speed 6,300 r/min (mechanical)." }, { "q": "What does the designation 51305 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 05: bore 25 mm (code 05 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51305-SKF need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.018 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51305", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51305-SKF", "51305" ], "locale_variants": {} }, { "sku": "51405-SKF", "brand": "SKF", "manufacturer_designation": "51405", "series": "51400-series", "type": "thrust_ball", "d_mm": 25, "D_mm": 60, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 42.3, "static_load_kN": 67, "fatigue_load_limit_kN": 2.45, "reference_speed_rpm": 3600, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 340, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51400 series order number 51405 is a SKF single-direction thrust ball bearing for a 25 mm seat, built to ISO 104, with a flat housing seating surface, 25×60×24 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 05 decodes to 25 mm (code 05 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 25×60×24 mm (0.984×2.362×0.945 in), 17.5 mm radial section, C 42.3 kN, C0 67 kN, Pu 2.45 kN. reference speed 3,600 r/min (thermal) and limiting speed 5,000 r/min (mechanical), catalogue mass 340 g. Static-first selection data: 67 kN C0 spread across the 24 mm stack gives 2.8 kN of static rating per height millimetre, and the 340 g mass/C0 ratio is about 5 g per static kN — crane-hook and screw positions are normally sized on these two figures. At the printed limiting speed of 5,000 r/min the mean pitch diameter dm ≈ 42.5 mm implies a dn value around 213k mm·r/min; the 3,600 r/min reference speed is the thermal-planning value under catalogue load. Selection figures for 51405: the C0/C ratio is 1.58, Pu 2.45 kN is about 6 % of C, and the catalogue mass works out to roughly 14 g per millimetre of bore; the printed minimum-load factor is A 0.048. Mass and section check: 340 g inside the 25×60×24 mm outline leaves a 17.5 mm radial section, and the 67 kN static rating is 1.58× the dynamic rating — plan static safety and minimum preload against those figures. Speed-ratio note for this exact unit: the reference speed is 3,600 r/min against a 5,000 r/min limiting speed, a reference-to-limit ratio of 0.72. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 25 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 42.3/67 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "screw jacks and press-adjustment spindles", "low-speed reducer thrust positions", "crane hooks and lifting-block pins" ], "failure_modes": [ "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 42.3 kN track before first rotation.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51405 against two-way load lifts the loose washer off its raceway.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.048; for 51405 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The 51405 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 25 mm shaft has to be carried by a radial bearing mounted alongside it.", "The 42.3/67 kN figures belong to 51405 specifically (the single flat pressed steel execution of 51405); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51405-SKF?", "a": "Boundary dimensions to ISO 104: bore 25 mm, OD 60 mm, height 24 mm; weight 340 g. Load figures from SKF 17000: dynamic 42.3 kN, static 67 kN, fatigue limit 2.45 kN; reference speed 3,600 r/min (thermal) and limiting speed 5,000 r/min (mechanical)." }, { "q": "What does the designation 51405 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 05 decodes to 25 mm (code 05 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51405-SKF?", "a": "The 3,600 r/min reference speed is the thermal balance under catalogue load; the 5,000 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51405-SKF need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.048 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51405", "equiv_brand": "NTN", "level": "partial", "note": "Same 25×60×24 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51405-SKF", "51405" ], "locale_variants": {} }, { "sku": "51106-SKF", "brand": "SKF", "manufacturer_designation": "51106", "series": "51100-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 47, "B_mm": 11, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19, "static_load_kN": 43, "fatigue_load_limit_kN": 1.6, "reference_speed_rpm": 6000, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 63, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51106 is SKF's 30 mm-bore single-direction thrust ball bearing in the 51100 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 30×47×11 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 06 encode the bore as 30 mm (code 06 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 30×47×11 mm (1.181×1.85×0.433 in), 8.5 mm radial section, C 19 kN, C0 43 kN, Pu 1.6 kN. reference speed 6,000 r/min (thermal) and limiting speed 8,500 r/min (mechanical), catalogue mass 63 g. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51106 covers about 1,028 mm², distributing C0 43 kN over a mean track circle of π·dm ≈ 121 mm. Imperial cross-check for procurement drawings: 1.181 in bore, 1.85 in OD, 0.433 in height, and the 63 g catalogue mass converts to 0.063 kg (2.2 oz). Stack/annulus proportions: the 11 mm axial stack over the 1,028 mm² washer annulus gives 10.70 mm of height per annular square millimetre ×10⁻³, and at 63 g the bearing holds about 682.5 kN of C0 per kilogram. Speed-ratio note for this exact unit: the reference speed is 6,000 r/min against a 8,500 r/min limiting speed, a reference-to-limit ratio of 0.71. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.0096 at the 8,500 r/min limiting speed raises the required axial preload to about 1.0 kN; the reference-speed value 512 N is the thermal design point. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 30 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 19/43 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "machine-tool adjustment screws and tailstock centres", "crane hooks and lifting-block pins", "low-speed reducer thrust positions" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 11 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "When the housing seat cannot be machined square to the 30 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 19 kN track before first rotation.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51106 as the single flat pressed steel execution; other order numbers of the 51106 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51106-SKF?", "a": "51106 measures 30 mm bore × 47 mm OD × 11 mm bearing height (1.181 × 1.85 × 0.433 in), mass about 63 g. SKF 17000 ratings: C 19 kN, C0 43 kN, Pu 1.6 kN, reference speed 6,000 r/min (thermal) and limiting speed 8,500 r/min (mechanical)." }, { "q": "What does the designation 51106 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 06 encode the bore as 30 mm (code 06 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." }, { "q": "Can 51106-SKF carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 30 mm shaft must go to a separate radial bearing; mixed loading through 51106 edge-loads the balls and destroys the washers." } ], "cross_ref": [ { "equiv_sku": "51106", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51106-SKF", "51106" ], "locale_variants": {} }, { "sku": "51206-SKF", "brand": "SKF", "manufacturer_designation": "51206", "series": "51200-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 52, "B_mm": 16, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.1, "static_load_kN": 51, "fatigue_load_limit_kN": 1.86, "reference_speed_rpm": 4800, "limiting_speed_rpm": 6700, "max_rpm": 6700, "weight_g": 130, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51206 is SKF's 30 mm-bore single-direction thrust ball bearing in the 51200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 30×52×16 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 06 encode the bore as 30 mm (code 06 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 30×52×16 mm (1.181×2.047×0.63 in), 11.0 mm radial section, C 25.1 kN, C0 51 kN, Pu 1.86 kN. reference speed 4,800 r/min (thermal) and limiting speed 6,700 r/min (mechanical), catalogue mass 130 g. Mass and section check: 130 g inside the 30×52×16 mm outline leaves a 11.0 mm radial section, and the 51 kN static rating is 2.03× the dynamic rating — plan static safety and minimum preload against those figures. Minimum-load arithmetic: with dm ≈ 41.0 mm and factor A 0.013, Fam ≈ A·(n·dm/1000)² at the 4,800 r/min reference speed is about 503 N for 51206; below that preload the balls skid and smear the tracks. Speed-ratio note for this exact unit: the reference speed is 4,800 r/min against a 6,700 r/min limiting speed, a reference-to-limit ratio of 0.72. Capacity density: 25.1 kN C from 0.130 kg of bearing steel gives about 193.1 kN per kilogram; static density is correspondingly 392.3 kN/kg at C0 51 kN. Section proportions: the 11.0 mm radial section compares with 30 mm of bore (section/bore ≈ 0.37) and the 16 mm height is 1.45× that section — the proportions that identify the 51200 envelope at a glance. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 30 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 25.1/51 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "machine-tool adjustment screws and tailstock centres", "screw jacks and press-adjustment spindles", "low-speed reducer thrust positions" ], "failure_modes": [ "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "washer face scoring from swarf trapped between the loose housing washer and its register", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "When the housing seat cannot be machined square to the 30 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 30 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.013; for 51206 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The 25.1/51 kN figures belong to 51206 specifically (the single flat pressed steel execution of 51206); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51206-SKF?", "a": "51206 measures 30 mm bore × 52 mm OD × 16 mm bearing height (1.181 × 2.047 × 0.63 in), mass about 130 g. SKF 17000 ratings: C 25.1 kN, C0 51 kN, Pu 1.86 kN, reference speed 4,800 r/min (thermal) and limiting speed 6,700 r/min (mechanical)." }, { "q": "What does the designation 51206 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 06 encode the bore as 30 mm (code 06 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can 51206-SKF carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 30 mm shaft must go to a separate radial bearing; mixed loading through 51206 edge-loads the balls and destroys the washers." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." } ], "cross_ref": [ { "equiv_sku": "51206", "equiv_brand": "NTN", "level": "partial", "note": "Same 30×52×16 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51206-SKF", "51206" ], "locale_variants": {} }, { "sku": "51306-SKF", "brand": "SKF", "manufacturer_designation": "51306", "series": "51300-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 60, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.8, "static_load_kN": 65.5, "fatigue_load_limit_kN": 2.4, "reference_speed_rpm": 3800, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 260, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51306 is SKF's 30 mm-bore single-direction thrust ball bearing in the 51300 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 30×60×21 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 06 encode the bore as 30 mm (code 06 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 30×60×21 mm (1.181×2.362×0.827 in), 15.0 mm radial section, C 35.8 kN, C0 65.5 kN, Pu 2.4 kN. reference speed 3,800 r/min (thermal) and limiting speed 5,300 r/min (mechanical), catalogue mass 260 g. Bore-to-OD planning: OD 60 over bore 30 is a 2.00× step for this size, and the 21 mm height gives a bore/height ratio of 1.43; use these ratios when the housing recess around the 30 mm shaft is the first constraint. Envelope economics: the 21 mm axial height over a 15.0 mm radial section yields 1.7 kN of dynamic capacity per height millimetre, and the bearing weighs 260 g for 35.8 kN C — about 7 g per rated kN. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 5,300 r/min while thermal balance under catalogue load sets the 3,800 r/min reference; at dm ≈ 45.0 mm the corresponding dn is approximately 239k mm·r/min. Rating split for documentation: dynamic 35.8 kN (L10 life), static 65.5 kN (safety factor s0), fatigue limit 2.4 kN (adjusted life) — three different uses of three different numbers for 51306, none interchangeable with another. Section proportions: the 15.0 mm radial section compares with 30 mm of bore (section/bore ≈ 0.50) and the 21 mm height is 1.40× that section — the proportions that identify the 51300 envelope at a glance. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 30 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 35.8/65.5 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "vertical pump and motor shaft thrust", "low-speed reducer thrust positions", "crane hooks and lifting-block pins" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "When the housing seat cannot be machined square to the 30 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51300 bearing.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 30 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 21 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Ordering discipline for 51306: the catalogue page quotes 51306 and its 35.8/65.5 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51306-SKF?", "a": "51306 measures 30 mm bore × 60 mm OD × 21 mm bearing height (1.181 × 2.362 × 0.827 in), mass about 260 g. SKF 17000 ratings: C 35.8 kN, C0 65.5 kN, Pu 2.4 kN, reference speed 3,800 r/min (thermal) and limiting speed 5,300 r/min (mechanical)." }, { "q": "What does the designation 51306 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 06 encode the bore as 30 mm (code 06 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." }, { "q": "How is 51306-SKF lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 5,300 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "51306", "equiv_brand": "NTN", "level": "partial", "note": "Same 30×60×21 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51306-SKF", "51306" ], "locale_variants": {} }, { "sku": "51406-SKF", "brand": "SKF", "manufacturer_designation": "51406", "series": "51400-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 70, "B_mm": 28, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 70.2, "static_load_kN": 122, "fatigue_load_limit_kN": 4.5, "reference_speed_rpm": 3000, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 520, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51406 is an ISO 104 single-direction thrust ball bearing, 30 mm bore and 70 mm OD on a flat housing seat, standing 28 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 06: bore 30 mm (code 06 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 30×70×28 mm (1.181×2.756×1.102 in), 20.0 mm radial section, C 70.2 kN, C0 122 kN, Pu 4.5 kN. reference speed 3,000 r/min (thermal) and limiting speed 4,300 r/min (mechanical), catalogue mass 520 g. At the printed limiting speed of 4,300 r/min the mean pitch diameter dm ≈ 50.0 mm implies a dn value around 215k mm·r/min; the 3,000 r/min reference speed is the thermal-planning value under catalogue load. Mass and section check: 520 g inside the 30×70×28 mm outline leaves a 20.0 mm radial section, and the 122 kN static rating is 1.74× the dynamic rating — plan static safety and minimum preload against those figures. Pitch-diameter arithmetic: dm = (30+70)/2 = 50.0 mm; at the 4,300 r/min limiting speed that corresponds to roughly 215k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Rating split for documentation: dynamic 70.2 kN (L10 life), static 122 kN (safety factor s0), fatigue limit 4.5 kN (adjusted life) — three different uses of three different numbers for 51406, none interchangeable with another. Minimum-load arithmetic: with dm ≈ 50.0 mm and factor A 0.097, Fam ≈ A·(n·dm/1000)² at the 3,000 r/min reference speed is about 2.2 kN for 51406; below that preload the balls skid and smear the tracks. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 28 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 70.2 kN C.", "applications": [ "vertical pump and motor shaft thrust", "machine-tool adjustment screws and tailstock centres", "low-speed reducer thrust positions" ], "failure_modes": [ "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "cage damage from mounting force applied through the balls instead of the washer face", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51406 against two-way load lifts the loose washer off its raceway.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 28 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 30 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51406 as the single flat pressed steel execution; other order numbers of the 51406 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51406-SKF?", "a": "The catalogue envelope is 30×70×28 mm, mass 520 g; ratings C 70.2 kN / C0 122 kN / Pu 4.5 kN, reference speed 3,000 r/min (thermal) and limiting speed 4,300 r/min (mechanical)." }, { "q": "What does the designation 51406 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 06: bore 30 mm (code 06 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51406-SKF lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 4,300 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 30 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51406", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51406-SKF", "51406" ], "locale_variants": {} }, { "sku": "51107-SKF", "brand": "SKF", "manufacturer_designation": "51107", "series": "51100-series", "type": "thrust_ball", "d_mm": 35, "D_mm": 52, "B_mm": 12, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.9, "static_load_kN": 51, "fatigue_load_limit_kN": 1.86, "reference_speed_rpm": 5600, "limiting_speed_rpm": 7500, "max_rpm": 7500, "weight_g": 80, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51107 is a SKF single-direction thrust ball bearing for a 35 mm seat, built to ISO 104, with a flat housing seating surface, 35×52×12 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 07 decodes to 35 mm (code 07 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 35×52×12 mm (1.378×2.047×0.472 in), 8.5 mm radial section, C 19.9 kN, C0 51 kN, Pu 1.86 kN. reference speed 5,600 r/min (thermal) and limiting speed 7,500 r/min (mechanical), catalogue mass 80 g. Load balance: C0 51 kN against C 19.9 kN gives a 2.56 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 1.86 kN enters the adjusted-life check. Sizing arithmetic on the 35 mm bore: 19.9 kN C over the 8.5 mm radial section gives 2.3 kN per section millimetre, and the 12 mm stack height is 1.41× that section — proportions typical of a 51100 thrust section. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51107 covers about 1,162 mm², distributing C0 51 kN over a mean track circle of π·dm ≈ 137 mm. Rating split for documentation: dynamic 19.9 kN (L10 life), static 51 kN (safety factor s0), fatigue limit 1.86 kN (adjusted life) — three different uses of three different numbers for 51107, none interchangeable with another. Imperial cross-check for procurement drawings: 1.378 in bore, 2.047 in OD, 0.472 in height, and the 80 g catalogue mass converts to 0.080 kg (2.8 oz). Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 35 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 19.9/51 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "vertical pump and motor shaft thrust", "screw jacks and press-adjustment spindles", "machine-tool adjustment screws and tailstock centres" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "washer face scoring from swarf trapped between the loose housing washer and its register", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 19.9 kN track before first rotation.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 35 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "When the housing seat cannot be machined square to the 35 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 19.9/51 kN and the available 52 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The 19.9/51 kN figures belong to 51107 specifically (the single flat pressed steel execution of 51107); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51107-SKF?", "a": "Boundary dimensions to ISO 104: bore 35 mm, OD 52 mm, height 12 mm; weight 80 g. Load figures from SKF 17000: dynamic 19.9 kN, static 51 kN, fatigue limit 1.86 kN; reference speed 5,600 r/min (thermal) and limiting speed 7,500 r/min (mechanical)." }, { "q": "What does the designation 51107 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 07 decodes to 35 mm (code 07 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51107-SKF need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.013 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51107", "equiv_brand": "NTN", "level": "partial", "note": "Same 35×52×12 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51107-SKF", "51107" ], "locale_variants": {} }, { "sku": "51207-SKF", "brand": "SKF", "manufacturer_designation": "51207", "series": "51200-series", "type": "thrust_ball", "d_mm": 35, "D_mm": 62, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 73.5, "fatigue_load_limit_kN": 2.7, "reference_speed_rpm": 4000, "limiting_speed_rpm": 5600, "max_rpm": 5600, "weight_g": 220, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51207 is an ISO 104 single-direction thrust ball bearing, 35 mm bore and 62 mm OD on a flat housing seat, standing 18 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 07: bore 35 mm (code 07 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 35×62×18 mm (1.378×2.441×0.709 in), 13.5 mm radial section, C 35.1 kN, C0 73.5 kN, Pu 2.7 kN. reference speed 4,000 r/min (thermal) and limiting speed 5,600 r/min (mechanical), catalogue mass 220 g. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.028 at the 5,600 r/min limiting speed raises the required axial preload to about 2.1 kN; the reference-speed value 1.1 kN is the thermal design point. Bore-to-OD planning: OD 62 over bore 35 is a 1.77× step for this size, and the 18 mm height gives a bore/height ratio of 1.94; use these ratios when the housing recess around the 35 mm shaft is the first constraint. Stack/annulus proportions: the 18 mm axial stack over the 2,057 mm² washer annulus gives 8.75 mm of height per annular square millimetre ×10⁻³, and at 220 g the bearing holds about 334.1 kN of C0 per kilogram. At the printed limiting speed of 5,600 r/min the mean pitch diameter dm ≈ 48.5 mm implies a dn value around 272k mm·r/min; the 4,000 r/min reference speed is the thermal-planning value under catalogue load. Pitch-diameter arithmetic: dm = (35+62)/2 = 48.5 mm; at the 5,600 r/min limiting speed that corresponds to roughly 272k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 18 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 35.1 kN C.", "applications": [ "machine-tool adjustment screws and tailstock centres", "crane hooks and lifting-block pins", "low-speed reducer thrust positions" ], "failure_modes": [ "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 35.1/73.5 kN and the available 62 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 35 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 18 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51207 against two-way load lifts the loose washer off its raceway.", "Ordering discipline for 51207: the catalogue page quotes 51207 and its 35.1/73.5 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51207-SKF?", "a": "The catalogue envelope is 35×62×18 mm, mass 220 g; ratings C 35.1 kN / C0 73.5 kN / Pu 2.7 kN, reference speed 4,000 r/min (thermal) and limiting speed 5,600 r/min (mechanical)." }, { "q": "What does the designation 51207 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 07: bore 35 mm (code 07 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." }, { "q": "How is 51207-SKF lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 5,600 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "51207", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51207-SKF", "51207" ], "locale_variants": {} }, { "sku": "51307-SKF", "brand": "SKF", "manufacturer_designation": "51307", "series": "51300-series", "type": "thrust_ball", "d_mm": 35, "D_mm": 68, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 49.4, "static_load_kN": 96.5, "fatigue_load_limit_kN": 3.55, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 390, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51307 is an ISO 104 single-direction thrust ball bearing, 35 mm bore and 68 mm OD on a flat housing seat, standing 24 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 07: bore 35 mm (code 07 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 35×68×24 mm (1.378×2.677×0.945 in), 16.5 mm radial section, C 49.4 kN, C0 96.5 kN, Pu 3.55 kN. reference speed 3,400 r/min (thermal) and limiting speed 4,800 r/min (mechanical), catalogue mass 390 g. Pitch-diameter arithmetic: dm = (35+68)/2 = 51.5 mm; at the 4,800 r/min limiting speed that corresponds to roughly 247k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.048 at the 4,800 r/min limiting speed raises the required axial preload to about 2.9 kN; the reference-speed value 1.5 kN is the thermal design point. At the printed limiting speed of 4,800 r/min the mean pitch diameter dm ≈ 51.5 mm implies a dn value around 247k mm·r/min; the 3,400 r/min reference speed is the thermal-planning value under catalogue load. Rating split for documentation: dynamic 49.4 kN (L10 life), static 96.5 kN (safety factor s0), fatigue limit 3.55 kN (adjusted life) — three different uses of three different numbers for 51307, none interchangeable with another. Stack/annulus proportions: the 24 mm axial stack over the 2,670 mm² washer annulus gives 8.99 mm of height per annular square millimetre ×10⁻³, and at 390 g the bearing holds about 247.4 kN of C0 per kilogram. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 35 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 49.4/96.5 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "low-speed reducer thrust positions", "crane hooks and lifting-block pins", "machine-tool adjustment screws and tailstock centres" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "false brinelling of the stationary tracks while the machine stands under vibration", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 49.4/96.5 kN and the available 68 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 24 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The 51307 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 35 mm shaft has to be carried by a radial bearing mounted alongside it.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51307 against two-way load lifts the loose washer off its raceway.", "Ordering discipline for 51307: the catalogue page quotes 51307 and its 49.4/96.5 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51307-SKF?", "a": "The catalogue envelope is 35×68×24 mm, mass 390 g; ratings C 49.4 kN / C0 96.5 kN / Pu 3.55 kN, reference speed 3,400 r/min (thermal) and limiting speed 4,800 r/min (mechanical)." }, { "q": "What does the designation 51307 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 07: bore 35 mm (code 07 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can 51307-SKF carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 35 mm shaft must go to a separate radial bearing; mixed loading through 51307 edge-loads the balls and destroys the washers." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." } ], "cross_ref": [ { "equiv_sku": "51307", "equiv_brand": "NTN", "level": "partial", "note": "Same 35×68×24 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51307-SKF", "51307" ], "locale_variants": {} }, { "sku": "51407-SKF", "brand": "SKF", "manufacturer_designation": "51407", "series": "51400-series", "type": "thrust_ball", "d_mm": 35, "D_mm": 80, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 76.1, "static_load_kN": 137, "fatigue_load_limit_kN": 5.1, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 790, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51400 series order number 51407 is a SKF single-direction thrust ball bearing for a 35 mm seat, built to ISO 104, with a flat housing seating surface, 35×80×32 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 07 decodes to 35 mm (code 07 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 35×80×32 mm (1.378×3.15×1.26 in), 22.5 mm radial section, C 76.1 kN, C0 137 kN, Pu 5.1 kN. reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical), catalogue mass 790 g. Speed band width for this size is 1,000 r/min between reference and limiting (1.38× ratio); lubrication, preload and heat removal decide where inside that band 51407 can actually run. Track-circle loading: per millimetre of mean track circumference the 76.1 kN dynamic rating corresponds to roughly 0.42 kN/mm of π·dm track, a useful comparison against the other dimension series of the 35 mm bore. Capacity density: 76.1 kN C from 0.790 kg of bearing steel gives about 96.3 kN per kilogram; static density is correspondingly 173.4 kN/kg at C0 137 kN. Section proportions: the 22.5 mm radial section compares with 35 mm of bore (section/bore ≈ 0.64) and the 32 mm height is 1.42× that section — the proportions that identify the 51400 envelope at a glance. Envelope economics: the 32 mm axial height over a 22.5 mm radial section yields 2.4 kN of dynamic capacity per height millimetre, and the bearing weighs 790 g for 76.1 kN C — about 10 g per rated kN. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 32 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 76.1 kN C.", "applications": [ "crane hooks and lifting-block pins", "screw jacks and press-adjustment spindles", "vertical pump and motor shaft thrust" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "pitting on one track sector from a perpetually eccentric thrust line", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "overheating from grease overfill churning inside a sealed housing recess with no escape volume" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "The 51407 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 35 mm shaft has to be carried by a radial bearing mounted alongside it.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.15; for 51407 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51407 against two-way load lifts the loose washer off its raceway.", "The 76.1/137 kN figures belong to 51407 specifically (the single flat pressed steel execution of 51407); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51407-SKF?", "a": "Boundary dimensions to ISO 104: bore 35 mm, OD 80 mm, height 32 mm; weight 790 g. Load figures from SKF 17000: dynamic 76.1 kN, static 137 kN, fatigue limit 5.1 kN; reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical)." }, { "q": "What does the designation 51407 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 07 decodes to 35 mm (code 07 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 35 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51407 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51407", "equiv_brand": "NTN", "level": "partial", "note": "Same 35×80×32 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51407-SKF", "51407" ], "locale_variants": {} }, { "sku": "51108-SKF", "brand": "SKF", "manufacturer_designation": "51108", "series": "51100-series", "type": "thrust_ball", "d_mm": 40, "D_mm": 60, "B_mm": 13, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 63, "fatigue_load_limit_kN": 2.32, "reference_speed_rpm": 5000, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51108 is SKF's 40 mm-bore single-direction thrust ball bearing in the 51100 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 40×60×13 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 08 encode the bore as 40 mm (code 08 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 40×60×13 mm (1.575×2.362×0.512 in), 10.0 mm radial section, C 25.5 kN, C0 63 kN, Pu 2.32 kN. reference speed 5,000 r/min (thermal) and limiting speed 7,000 r/min (mechanical), catalogue mass 120 g. Static-first selection data: 63 kN C0 spread across the 13 mm stack gives 4.8 kN of static rating per height millimetre, and the 120 g mass/C0 ratio is about 2 g per static kN — crane-hook and screw positions are normally sized on these two figures. Capacity density: 25.5 kN C from 0.120 kg of bearing steel gives about 212.5 kN per kilogram; static density is correspondingly 525.0 kN/kg at C0 63 kN. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51108 covers about 1,571 mm², distributing C0 63 kN over a mean track circle of π·dm ≈ 157 mm. Sizing arithmetic on the 40 mm bore: 25.5 kN C over the 10.0 mm radial section gives 2.5 kN per section millimetre, and the 13 mm stack height is 1.30× that section — proportions typical of a 51100 thrust section. Imperial cross-check for procurement drawings: 1.575 in bore, 2.362 in OD, 0.512 in height, and the 120 g catalogue mass converts to 0.120 kg (4.2 oz). Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 40 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 25.5/63 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "vertical pump and motor shaft thrust", "screw jacks and press-adjustment spindles", "low-speed reducer thrust positions" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "pitting on one track sector from a perpetually eccentric thrust line", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 25.5 kN track before first rotation.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 13 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 40 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51108 against two-way load lifts the loose washer off its raceway.", "The 25.5/63 kN figures belong to 51108 specifically (the single flat pressed steel execution of 51108); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51108-SKF?", "a": "51108 measures 40 mm bore × 60 mm OD × 13 mm bearing height (1.575 × 2.362 × 0.512 in), mass about 120 g. SKF 17000 ratings: C 25.5 kN, C0 63 kN, Pu 2.32 kN, reference speed 5,000 r/min (thermal) and limiting speed 7,000 r/min (mechanical)." }, { "q": "What does the designation 51108 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 08 encode the bore as 40 mm (code 08 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51108-SKF?", "a": "The 5,000 r/min reference speed is the thermal balance under catalogue load; the 7,000 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51108-SKF need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.02 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51108", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51108-SKF", "51108" ], "locale_variants": {} }, { "sku": "51208-SKF", "brand": "SKF", "manufacturer_designation": "51208", "series": "51200-series", "type": "thrust_ball", "d_mm": 40, "D_mm": 68, "B_mm": 19, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 44.2, "static_load_kN": 96.5, "fatigue_load_limit_kN": 3.6, "reference_speed_rpm": 3800, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 280, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51208 is SKF's 40 mm-bore single-direction thrust ball bearing in the 51200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 40×68×19 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 08 encode the bore as 40 mm (code 08 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 40×68×19 mm (1.575×2.677×0.748 in), 14.0 mm radial section, C 44.2 kN, C0 96.5 kN, Pu 3.6 kN. reference speed 3,800 r/min (thermal) and limiting speed 5,300 r/min (mechanical), catalogue mass 280 g. Speed-ratio note for this exact unit: the reference speed is 3,800 r/min against a 5,300 r/min limiting speed, a reference-to-limit ratio of 0.72. Stack/annulus proportions: the 19 mm axial stack over the 2,375 mm² washer annulus gives 8.00 mm of height per annular square millimetre ×10⁻³, and at 280 g the bearing holds about 344.6 kN of C0 per kilogram. Light-load floor: Pu = 3.6 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51208; the number is 8 % of the 44.2 kN dynamic rating. Capacity density: 44.2 kN C from 0.280 kg of bearing steel gives about 157.9 kN per kilogram; static density is correspondingly 344.6 kN/kg at C0 96.5 kN. Track-circle loading: per millimetre of mean track circumference the 44.2 kN dynamic rating corresponds to roughly 0.26 kN/mm of π·dm track, a useful comparison against the other dimension series of the 40 mm bore. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 19 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 44.2 kN C.", "applications": [ "machine-tool adjustment screws and tailstock centres", "screw jacks and press-adjustment spindles", "vertical pump and motor shaft thrust" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "washer face scoring from swarf trapped between the loose housing washer and its register", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.058; for 51208 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51208 against two-way load lifts the loose washer off its raceway.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "The 51208 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 40 mm shaft has to be carried by a radial bearing mounted alongside it.", "Ordering discipline for 51208: the catalogue page quotes 51208 and its 44.2/96.5 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51208-SKF?", "a": "51208 measures 40 mm bore × 68 mm OD × 19 mm bearing height (1.575 × 2.677 × 0.748 in), mass about 280 g. SKF 17000 ratings: C 44.2 kN, C0 96.5 kN, Pu 3.6 kN, reference speed 3,800 r/min (thermal) and limiting speed 5,300 r/min (mechanical)." }, { "q": "What does the designation 51208 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 08 encode the bore as 40 mm (code 08 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51208-SKF lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 5,300 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 40 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51208", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51208-SKF", "51208" ], "locale_variants": {} }, { "sku": "51308-SKF", "brand": "SKF", "manufacturer_designation": "51308", "series": "51300-series", "type": "thrust_ball", "d_mm": 40, "D_mm": 78, "B_mm": 26, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 61.8, "static_load_kN": 122, "fatigue_load_limit_kN": 4.5, "reference_speed_rpm": 3000, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 530, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51308 is SKF's 40 mm-bore single-direction thrust ball bearing in the 51300 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 40×78×26 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 08 encode the bore as 40 mm (code 08 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 40×78×26 mm (1.575×3.071×1.024 in), 19.0 mm radial section, C 61.8 kN, C0 122 kN, Pu 4.5 kN. reference speed 3,000 r/min (thermal) and limiting speed 4,300 r/min (mechanical), catalogue mass 530 g. Mass and section check: 530 g inside the 40×78×26 mm outline leaves a 19.0 mm radial section, and the 122 kN static rating is 1.97× the dynamic rating — plan static safety and minimum preload against those figures. Envelope economics: the 26 mm axial height over a 19.0 mm radial section yields 2.4 kN of dynamic capacity per height millimetre, and the bearing weighs 530 g for 61.8 kN C — about 9 g per rated kN. Minimum-load arithmetic: with dm ≈ 59.0 mm and factor A 0.077, Fam ≈ A·(n·dm/1000)² at the 3,000 r/min reference speed is about 2.4 kN for 51308; below that preload the balls skid and smear the tracks. Imperial cross-check for procurement drawings: 1.575 in bore, 3.071 in OD, 1.024 in height, and the 530 g catalogue mass converts to 0.530 kg (18.7 oz). Rating split for documentation: dynamic 61.8 kN (L10 life), static 122 kN (safety factor s0), fatigue limit 4.5 kN (adjusted life) — three different uses of three different numbers for 51308, none interchangeable with another. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 26 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 61.8 kN C.", "applications": [ "screw jacks and press-adjustment spindles", "crane hooks and lifting-block pins", "low-speed reducer thrust positions" ], "failure_modes": [ "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "track rust staining from condensate during long idle periods in humid plant air" ], "pitfalls": [ "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 40 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "The 51308 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 40 mm shaft has to be carried by a radial bearing mounted alongside it.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "When the housing seat cannot be machined square to the 40 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51300 bearing.", "The 61.8/122 kN figures belong to 51308 specifically (the single flat pressed steel execution of 51308); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51308-SKF?", "a": "51308 measures 40 mm bore × 78 mm OD × 26 mm bearing height (1.575 × 3.071 × 1.024 in), mass about 530 g. SKF 17000 ratings: C 61.8 kN, C0 122 kN, Pu 4.5 kN, reference speed 3,000 r/min (thermal) and limiting speed 4,300 r/min (mechanical)." }, { "q": "What does the designation 51308 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 08 encode the bore as 40 mm (code 08 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 40 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51308 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51308", "equiv_brand": "NTN", "level": "partial", "note": "Same 40×78×26 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51308-SKF", "51308" ], "locale_variants": {} }, { "sku": "51408-SKF", "brand": "SKF", "manufacturer_designation": "51408", "series": "51400-series", "type": "thrust_ball", "d_mm": 40, "D_mm": 90, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 95.6, "static_load_kN": 183, "fatigue_load_limit_kN": 6.8, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51408 is an ISO 104 single-direction thrust ball bearing, 40 mm bore and 90 mm OD on a flat housing seat, standing 36 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 08: bore 40 mm (code 08 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 40×90×36 mm (1.575×3.543×1.417 in), 25.0 mm radial section, C 95.6 kN, C0 183 kN, Pu 6.8 kN. reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical), catalogue mass 1100 g. Stack/annulus proportions: the 36 mm axial stack over the 5,105 mm² washer annulus gives 7.05 mm of height per annular square millimetre ×10⁻³, and at 1100 g the bearing holds about 166.4 kN of C0 per kilogram. Speed band width for this size is 1,000 r/min between reference and limiting (1.42× ratio); lubrication, preload and heat removal decide where inside that band 51408 can actually run. Imperial cross-check for procurement drawings: 1.575 in bore, 3.543 in OD, 1.417 in height, and the 1100 g catalogue mass converts to 1.100 kg (38.8 oz). Rating split for documentation: dynamic 95.6 kN (L10 life), static 183 kN (safety factor s0), fatigue limit 6.8 kN (adjusted life) — three different uses of three different numbers for 51408, none interchangeable with another. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.26 at the 3,400 r/min limiting speed raises the required axial preload to about 12.7 kN; the reference-speed value 6.3 kN is the thermal design point. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 40 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 95.6/183 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "machine-tool adjustment screws and tailstock centres", "crane hooks and lifting-block pins", "screw jacks and press-adjustment spindles" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "false brinelling of the stationary tracks while the machine stands under vibration", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 36 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "The 51408 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 40 mm shaft has to be carried by a radial bearing mounted alongside it.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.26; for 51408 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51408 as the single flat pressed steel execution; other order numbers of the 51408 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51408-SKF?", "a": "The catalogue envelope is 40×90×36 mm, mass 1100 g; ratings C 95.6 kN / C0 183 kN / Pu 6.8 kN, reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical)." }, { "q": "What does the designation 51408 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 08: bore 40 mm (code 08 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can 51408-SKF carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 40 mm shaft must go to a separate radial bearing; mixed loading through 51408 edge-loads the balls and destroys the washers." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." } ], "cross_ref": [ { "equiv_sku": "51408", "equiv_brand": "NTN", "level": "partial", "note": "Same 40×90×36 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51408-SKF", "51408" ], "locale_variants": {} }, { "sku": "51109-SKF", "brand": "SKF", "manufacturer_designation": "51109", "series": "51100-series", "type": "thrust_ball", "d_mm": 45, "D_mm": 65, "B_mm": 14, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 26.5, "static_load_kN": 69.5, "fatigue_load_limit_kN": 2.55, "reference_speed_rpm": 4500, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 140, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51109 is SKF's 45 mm-bore single-direction thrust ball bearing in the 51100 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 45×65×14 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 09 encode the bore as 45 mm (code 09 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 45×65×14 mm (1.772×2.559×0.551 in), 10.0 mm radial section, C 26.5 kN, C0 69.5 kN, Pu 2.55 kN. reference speed 4,500 r/min (thermal) and limiting speed 6,300 r/min (mechanical), catalogue mass 140 g. Minimum-load arithmetic: with dm ≈ 55.0 mm and factor A 0.025, Fam ≈ A·(n·dm/1000)² at the 4,500 r/min reference speed is about 1.5 kN for 51109; below that preload the balls skid and smear the tracks. Load balance: C0 69.5 kN against C 26.5 kN gives a 2.62 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 2.55 kN enters the adjusted-life check. Bore-to-OD planning: OD 65 over bore 45 is a 1.44× step for this size, and the 14 mm height gives a bore/height ratio of 3.21; use these ratios when the housing recess around the 45 mm shaft is the first constraint. Light-load floor: Pu = 2.55 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51109; the number is 10 % of the 26.5 kN dynamic rating. Static-first selection data: 69.5 kN C0 spread across the 14 mm stack gives 5.0 kN of static rating per height millimetre, and the 140 g mass/C0 ratio is about 2 g per static kN — crane-hook and screw positions are normally sized on these two figures. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 45 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 26.5/69.5 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "vertical pump and motor shaft thrust", "machine-tool adjustment screws and tailstock centres", "low-speed reducer thrust positions" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "cage damage from mounting force applied through the balls instead of the washer face", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 26.5/69.5 kN and the available 65 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 26.5 kN track before first rotation.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.025; for 51109 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Ordering discipline for 51109: the catalogue page quotes 51109 and its 26.5/69.5 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51109-SKF?", "a": "51109 measures 45 mm bore × 65 mm OD × 14 mm bearing height (1.772 × 2.559 × 0.551 in), mass about 140 g. SKF 17000 ratings: C 26.5 kN, C0 69.5 kN, Pu 2.55 kN, reference speed 4,500 r/min (thermal) and limiting speed 6,300 r/min (mechanical)." }, { "q": "What does the designation 51109 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 09 encode the bore as 45 mm (code 09 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can a single 51109 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." }, { "q": "What do the two published speeds mean for 51109-SKF?", "a": "The 4,500 r/min reference speed is the thermal balance under catalogue load; the 6,300 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." } ], "cross_ref": [ { "equiv_sku": "51109", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51109-SKF", "51109" ], "locale_variants": {} }, { "sku": "51209-SKF", "brand": "SKF", "manufacturer_designation": "51209", "series": "51200-series", "type": "thrust_ball", "d_mm": 45, "D_mm": 73, "B_mm": 20, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 39, "static_load_kN": 86.5, "fatigue_load_limit_kN": 3.2, "reference_speed_rpm": 3600, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51209 is SKF's 45 mm-bore single-direction thrust ball bearing in the 51200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 45×73×20 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 09 encode the bore as 45 mm (code 09 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 45×73×20 mm (1.772×2.874×0.787 in), 14.0 mm radial section, C 39 kN, C0 86.5 kN, Pu 3.2 kN. reference speed 3,600 r/min (thermal) and limiting speed 5,000 r/min (mechanical), catalogue mass 300 g. Load balance: C0 86.5 kN against C 39 kN gives a 2.22 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 3.2 kN enters the adjusted-life check. Static-first selection data: 86.5 kN C0 spread across the 20 mm stack gives 4.3 kN of static rating per height millimetre, and the 300 g mass/C0 ratio is about 3 g per static kN — crane-hook and screw positions are normally sized on these two figures. Speed band width for this size is 1,400 r/min between reference and limiting (1.39× ratio); lubrication, preload and heat removal decide where inside that band 51209 can actually run. Sizing arithmetic on the 45 mm bore: 39 kN C over the 14.0 mm radial section gives 2.8 kN per section millimetre, and the 20 mm stack height is 1.43× that section — proportions typical of a 51200 thrust section. Track-circle loading: per millimetre of mean track circumference the 39 kN dynamic rating corresponds to roughly 0.21 kN/mm of π·dm track, a useful comparison against the other dimension series of the 45 mm bore. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 20 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 39 kN C.", "applications": [ "screw jacks and press-adjustment spindles", "low-speed reducer thrust positions", "crane hooks and lifting-block pins" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "When the housing seat cannot be machined square to the 45 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 45 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.038; for 51209 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Ordering discipline for 51209: the catalogue page quotes 51209 and its 39/86.5 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51209-SKF?", "a": "51209 measures 45 mm bore × 73 mm OD × 20 mm bearing height (1.772 × 2.874 × 0.787 in), mass about 300 g. SKF 17000 ratings: C 39 kN, C0 86.5 kN, Pu 3.2 kN, reference speed 3,600 r/min (thermal) and limiting speed 5,000 r/min (mechanical)." }, { "q": "What does the designation 51209 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 09 encode the bore as 45 mm (code 09 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 45 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51209 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51209", "equiv_brand": "NTN", "level": "partial", "note": "Same 45×73×20 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51209-SKF", "51209" ], "locale_variants": {} }, { "sku": "51309-SKF", "brand": "SKF", "manufacturer_designation": "51309", "series": "51300-series", "type": "thrust_ball", "d_mm": 45, "D_mm": 85, "B_mm": 28, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 76.1, "static_load_kN": 153, "fatigue_load_limit_kN": 5.6, "reference_speed_rpm": 2800, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 660, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51300 series order number 51309 is a SKF single-direction thrust ball bearing for a 45 mm seat, built to ISO 104, with a flat housing seating surface, 45×85×28 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 09 decodes to 45 mm (code 09 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 45×85×28 mm (1.772×3.346×1.102 in), 20.0 mm radial section, C 76.1 kN, C0 153 kN, Pu 5.6 kN. reference speed 2,800 r/min (thermal) and limiting speed 4,000 r/min (mechanical), catalogue mass 660 g. Light-load floor: Pu = 5.6 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51309; the number is 7 % of the 76.1 kN dynamic rating. Capacity density: 76.1 kN C from 0.660 kg of bearing steel gives about 115.3 kN per kilogram; static density is correspondingly 231.8 kN/kg at C0 153 kN. Section proportions: the 20.0 mm radial section compares with 45 mm of bore (section/bore ≈ 0.44) and the 28 mm height is 1.40× that section — the proportions that identify the 51300 envelope at a glance. Static-first selection data: 153 kN C0 spread across the 28 mm stack gives 5.5 kN of static rating per height millimetre, and the 660 g mass/C0 ratio is about 4 g per static kN — crane-hook and screw positions are normally sized on these two figures. Load balance: C0 153 kN against C 76.1 kN gives a 2.01 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 5.6 kN enters the adjusted-life check. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 45 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 76.1/153 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "vertical pump and motor shaft thrust", "screw jacks and press-adjustment spindles", "low-speed reducer thrust positions" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "washer face scoring from swarf trapped between the loose housing washer and its register", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51309 against two-way load lifts the loose washer off its raceway.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.12; for 51309 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 76.1/153 kN and the available 85 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51309 as the single flat pressed steel execution; other order numbers of the 51309 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51309-SKF?", "a": "Boundary dimensions to ISO 104: bore 45 mm, OD 85 mm, height 28 mm; weight 660 g. Load figures from SKF 17000: dynamic 76.1 kN, static 153 kN, fatigue limit 5.6 kN; reference speed 2,800 r/min (thermal) and limiting speed 4,000 r/min (mechanical)." }, { "q": "What does the designation 51309 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 09 decodes to 45 mm (code 09 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51309-SKF lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 4,000 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 45 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51309", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51309-SKF", "51309" ], "locale_variants": {} }, { "sku": "51409-SKF", "brand": "SKF", "manufacturer_designation": "51409", "series": "51400-series", "type": "thrust_ball", "d_mm": 45, "D_mm": 100, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 124, "static_load_kN": 240, "fatigue_load_limit_kN": 9, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51409 is SKF's 45 mm-bore single-direction thrust ball bearing in the 51400 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 45×100×39 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 09 encode the bore as 45 mm (code 09 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 45×100×39 mm (1.772×3.937×1.535 in), 27.5 mm radial section, C 124 kN, C0 240 kN, Pu 9 kN. reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical), catalogue mass 1400 g. Pitch-diameter arithmetic: dm = (45+100)/2 = 72.5 mm; at the 3,000 r/min limiting speed that corresponds to roughly 218k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Imperial cross-check for procurement drawings: 1.772 in bore, 3.937 in OD, 1.535 in height, and the 1400 g catalogue mass converts to 1.400 kg (49.4 oz). Light-load floor: Pu = 9 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51409; the number is 7 % of the 124 kN dynamic rating. Sizing arithmetic on the 45 mm bore: 124 kN C over the 27.5 mm radial section gives 4.5 kN per section millimetre, and the 39 mm stack height is 1.42× that section — proportions typical of a 51400 thrust section. Static-first selection data: 240 kN C0 spread across the 39 mm stack gives 6.2 kN of static rating per height millimetre, and the 1400 g mass/C0 ratio is about 6 g per static kN — crane-hook and screw positions are normally sized on these two figures. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 39 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 124 kN C.", "applications": [ "vertical pump and motor shaft thrust", "low-speed reducer thrust positions", "crane hooks and lifting-block pins" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51409 against two-way load lifts the loose washer off its raceway.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 45 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "When the housing seat cannot be machined square to the 45 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51400 bearing.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51409 as the single flat pressed steel execution; other order numbers of the 51409 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51409-SKF?", "a": "51409 measures 45 mm bore × 100 mm OD × 39 mm bearing height (1.772 × 3.937 × 1.535 in), mass about 1400 g. SKF 17000 ratings: C 124 kN, C0 240 kN, Pu 9 kN, reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical)." }, { "q": "What does the designation 51409 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 09 encode the bore as 45 mm (code 09 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." }, { "q": "How is 51409-SKF lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 3,000 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "51409", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51409-SKF", "51409" ], "locale_variants": {} }, { "sku": "51110-SKF", "brand": "SKF", "manufacturer_designation": "51110", "series": "51100-series", "type": "thrust_ball", "d_mm": 50, "D_mm": 70, "B_mm": 14, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 27, "static_load_kN": 75, "fatigue_load_limit_kN": 2.8, "reference_speed_rpm": 4300, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 160, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51110 is a SKF single-direction thrust ball bearing for a 50 mm seat, built to ISO 104, with a flat housing seating surface, 50×70×14 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 10 decodes to 50 mm (code 10 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 50×70×14 mm (1.969×2.756×0.551 in), 10.0 mm radial section, C 27 kN, C0 75 kN, Pu 2.8 kN. reference speed 4,300 r/min (thermal) and limiting speed 6,300 r/min (mechanical), catalogue mass 160 g. Speed-ratio note for this exact unit: the reference speed is 4,300 r/min against a 6,300 r/min limiting speed, a reference-to-limit ratio of 0.68. Sizing arithmetic on the 50 mm bore: 27 kN C over the 10.0 mm radial section gives 2.7 kN per section millimetre, and the 14 mm stack height is 1.40× that section — proportions typical of a 51100 thrust section. Minimum-load arithmetic: with dm ≈ 60.0 mm and factor A 0.029, Fam ≈ A·(n·dm/1000)² at the 4,300 r/min reference speed is about 1.9 kN for 51110; below that preload the balls skid and smear the tracks. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.029 at the 6,300 r/min limiting speed raises the required axial preload to about 4.1 kN; the reference-speed value 1.9 kN is the thermal design point. Speed band width for this size is 2,000 r/min between reference and limiting (1.47× ratio); lubrication, preload and heat removal decide where inside that band 51110 can actually run. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 14 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 27 kN C.", "applications": [ "vertical pump and motor shaft thrust", "crane hooks and lifting-block pins", "low-speed reducer thrust positions" ], "failure_modes": [ "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "cage damage from mounting force applied through the balls instead of the washer face", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51110 against two-way load lifts the loose washer off its raceway.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 27/75 kN and the available 70 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 14 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51110 as the single flat pressed steel execution; other order numbers of the 51110 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51110-SKF?", "a": "Boundary dimensions to ISO 104: bore 50 mm, OD 70 mm, height 14 mm; weight 160 g. Load figures from SKF 17000: dynamic 27 kN, static 75 kN, fatigue limit 2.8 kN; reference speed 4,300 r/min (thermal) and limiting speed 6,300 r/min (mechanical)." }, { "q": "What does the designation 51110 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 10 decodes to 50 mm (code 10 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51110-SKF need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.029 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51110", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51110-SKF", "51110" ], "locale_variants": {} }, { "sku": "51210-SKF", "brand": "SKF", "manufacturer_designation": "51210", "series": "51200-series", "type": "thrust_ball", "d_mm": 50, "D_mm": 78, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 49.4, "static_load_kN": 116, "fatigue_load_limit_kN": 4.3, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4500, "max_rpm": 4500, "weight_g": 370, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51200 series order number 51210 is a SKF single-direction thrust ball bearing for a 50 mm seat, built to ISO 104, with a flat housing seating surface, 50×78×22 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 10 decodes to 50 mm (code 10 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 50×78×22 mm (1.969×3.071×0.866 in), 14.0 mm radial section, C 49.4 kN, C0 116 kN, Pu 4.3 kN. reference speed 3,400 r/min (thermal) and limiting speed 4,500 r/min (mechanical), catalogue mass 370 g. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 4,500 r/min while thermal balance under catalogue load sets the 3,400 r/min reference; at dm ≈ 64.0 mm the corresponding dn is approximately 288k mm·r/min. Bore-to-OD planning: OD 78 over bore 50 is a 1.56× step for this size, and the 22 mm height gives a bore/height ratio of 2.27; use these ratios when the housing recess around the 50 mm shaft is the first constraint. Section proportions: the 14.0 mm radial section compares with 50 mm of bore (section/bore ≈ 0.28) and the 22 mm height is 1.57× that section — the proportions that identify the 51200 envelope at a glance. Light-load floor: Pu = 4.3 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51210; the number is 9 % of the 49.4 kN dynamic rating. Static-first selection data: 116 kN C0 spread across the 22 mm stack gives 5.3 kN of static rating per height millimetre, and the 370 g mass/C0 ratio is about 3 g per static kN — crane-hook and screw positions are normally sized on these two figures. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 50 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 49.4/116 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "low-speed reducer thrust positions", "screw jacks and press-adjustment spindles", "machine-tool adjustment screws and tailstock centres" ], "failure_modes": [ "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "pitting on one track sector from a perpetually eccentric thrust line", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 49.4 kN track before first rotation.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51210 against two-way load lifts the loose washer off its raceway.", "When the housing seat cannot be machined square to the 50 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "The 51210 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 50 mm shaft has to be carried by a radial bearing mounted alongside it.", "The 49.4/116 kN figures belong to 51210 specifically (the single flat pressed steel execution of 51210); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51210-SKF?", "a": "Boundary dimensions to ISO 104: bore 50 mm, OD 78 mm, height 22 mm; weight 370 g. Load figures from SKF 17000: dynamic 49.4 kN, static 116 kN, fatigue limit 4.3 kN; reference speed 3,400 r/min (thermal) and limiting speed 4,500 r/min (mechanical)." }, { "q": "What does the designation 51210 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 10 decodes to 50 mm (code 10 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." }, { "q": "How is 51210-SKF lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 4,500 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "51210", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51210-SKF", "51210" ], "locale_variants": {} }, { "sku": "51310-SKF", "brand": "SKF", "manufacturer_designation": "51310", "series": "51300-series", "type": "thrust_ball", "d_mm": 50, "D_mm": 95, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 81.9, "static_load_kN": 170, "fatigue_load_limit_kN": 6.3, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 940, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51310 is SKF's 50 mm-bore single-direction thrust ball bearing in the 51300 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 50×95×31 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 10 encode the bore as 50 mm (code 10 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 50×95×31 mm (1.969×3.74×1.22 in), 22.5 mm radial section, C 81.9 kN, C0 170 kN, Pu 6.3 kN. reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical), catalogue mass 940 g. Stack/annulus proportions: the 31 mm axial stack over the 5,125 mm² washer annulus gives 6.05 mm of height per annular square millimetre ×10⁻³, and at 940 g the bearing holds about 180.9 kN of C0 per kilogram. Selection figures for 51310: the C0/C ratio is 2.08, Pu 6.3 kN is about 8 % of C, and the catalogue mass works out to roughly 19 g per millimetre of bore; the printed minimum-load factor is A 0.19. Speed band width for this size is 1,000 r/min between reference and limiting (1.38× ratio); lubrication, preload and heat removal decide where inside that band 51310 can actually run. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 3,600 r/min while thermal balance under catalogue load sets the 2,600 r/min reference; at dm ≈ 72.5 mm the corresponding dn is approximately 261k mm·r/min. Capacity density: 81.9 kN C from 0.940 kg of bearing steel gives about 87.1 kN per kilogram; static density is correspondingly 180.9 kN/kg at C0 170 kN. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 50 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 81.9/170 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "vertical pump and motor shaft thrust", "crane hooks and lifting-block pins", "low-speed reducer thrust positions" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 81.9/170 kN and the available 95 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 81.9 kN track before first rotation.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.19; for 51310 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51310 against two-way load lifts the loose washer off its raceway.", "Ordering discipline for 51310: the catalogue page quotes 51310 and its 81.9/170 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51310-SKF?", "a": "51310 measures 50 mm bore × 95 mm OD × 31 mm bearing height (1.969 × 3.74 × 1.22 in), mass about 940 g. SKF 17000 ratings: C 81.9 kN, C0 170 kN, Pu 6.3 kN, reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical)." }, { "q": "What does the designation 51310 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 10 encode the bore as 50 mm (code 10 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can a single 51310 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." }, { "q": "What do the two published speeds mean for 51310-SKF?", "a": "The 2,600 r/min reference speed is the thermal balance under catalogue load; the 3,600 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." } ], "cross_ref": [ { "equiv_sku": "51310", "equiv_brand": "NTN", "level": "partial", "note": "Same 50×95×31 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51310-SKF", "51310" ], "locale_variants": {} }, { "sku": "51410-SKF", "brand": "SKF", "manufacturer_designation": "51410", "series": "51400-series", "type": "thrust_ball", "d_mm": 50, "D_mm": 110, "B_mm": 43, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 159, "static_load_kN": 340, "fatigue_load_limit_kN": 12.5, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 2000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51400 series order number 51410 is a SKF single-direction thrust ball bearing for a 50 mm seat, built to ISO 104, with a flat housing seating surface, 50×110×43 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 10 decodes to 50 mm (code 10 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 50×110×43 mm (1.969×4.331×1.693 in), 30.0 mm radial section, C 159 kN, C0 340 kN, Pu 12.5 kN. reference speed 2,000 r/min (thermal) and limiting speed 2,800 r/min (mechanical), catalogue mass 2000 g. Light-load floor: Pu = 12.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51410; the number is 8 % of the 159 kN dynamic rating. Bore-to-OD planning: OD 110 over bore 50 is a 2.20× step for this size, and the 43 mm height gives a bore/height ratio of 1.16; use these ratios when the housing recess around the 50 mm shaft is the first constraint. Speed band width for this size is 800 r/min between reference and limiting (1.40× ratio); lubrication, preload and heat removal decide where inside that band 51410 can actually run. Rating split for documentation: dynamic 159 kN (L10 life), static 340 kN (safety factor s0), fatigue limit 12.5 kN (adjusted life) — three different uses of three different numbers for 51410, none interchangeable with another. At the printed limiting speed of 2,800 r/min the mean pitch diameter dm ≈ 80.0 mm implies a dn value around 224k mm·r/min; the 2,000 r/min reference speed is the thermal-planning value under catalogue load. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 43 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 159 kN C.", "applications": [ "machine-tool adjustment screws and tailstock centres", "low-speed reducer thrust positions", "vertical pump and motor shaft thrust" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 50 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "The 51410 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 50 mm shaft has to be carried by a radial bearing mounted alongside it.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.6; for 51410 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "When the housing seat cannot be machined square to the 50 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51400 bearing.", "The 159/340 kN figures belong to 51410 specifically (the single flat pressed steel execution of 51410); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51410-SKF?", "a": "Boundary dimensions to ISO 104: bore 50 mm, OD 110 mm, height 43 mm; weight 2000 g. Load figures from SKF 17000: dynamic 159 kN, static 340 kN, fatigue limit 12.5 kN; reference speed 2,000 r/min (thermal) and limiting speed 2,800 r/min (mechanical)." }, { "q": "What does the designation 51410 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 10 decodes to 50 mm (code 10 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." }, { "q": "Can 51410-SKF carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 50 mm shaft must go to a separate radial bearing; mixed loading through 51410 edge-loads the balls and destroys the washers." } ], "cross_ref": [ { "equiv_sku": "51410", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51410-SKF", "51410" ], "locale_variants": {} }, { "sku": "51111-SKF", "brand": "SKF", "manufacturer_designation": "51111", "series": "51100-series", "type": "thrust_ball", "d_mm": 55, "D_mm": 78, "B_mm": 16, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.2, "static_load_kN": 81.5, "fatigue_load_limit_kN": 3, "reference_speed_rpm": 3800, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 230, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51111 is a SKF single-direction thrust ball bearing for a 55 mm seat, built to ISO 104, with a flat housing seating surface, 55×78×16 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 11 decodes to 55 mm (code 11 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 55×78×16 mm (2.165×3.071×0.63 in), 11.5 mm radial section, C 30.2 kN, C0 81.5 kN, Pu 3 kN. reference speed 3,800 r/min (thermal) and limiting speed 5,300 r/min (mechanical), catalogue mass 230 g. Light-load floor: Pu = 3 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51111; the number is 10 % of the 30.2 kN dynamic rating. Selection figures for 51111: the C0/C ratio is 2.70, Pu 3 kN is about 10 % of C, and the catalogue mass works out to roughly 4 g per millimetre of bore; the printed minimum-load factor is A 0.039. Mass and section check: 230 g inside the 55×78×16 mm outline leaves a 11.5 mm radial section, and the 81.5 kN static rating is 2.70× the dynamic rating — plan static safety and minimum preload against those figures. Rating split for documentation: dynamic 30.2 kN (L10 life), static 81.5 kN (safety factor s0), fatigue limit 3 kN (adjusted life) — three different uses of three different numbers for 51111, none interchangeable with another. At the printed limiting speed of 5,300 r/min the mean pitch diameter dm ≈ 66.5 mm implies a dn value around 352k mm·r/min; the 3,800 r/min reference speed is the thermal-planning value under catalogue load. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 16 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 30.2 kN C.", "applications": [ "machine-tool adjustment screws and tailstock centres", "low-speed reducer thrust positions", "screw jacks and press-adjustment spindles" ], "failure_modes": [ "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "false brinelling of the stationary tracks while the machine stands under vibration" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.039; for 51111 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 16 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "When the housing seat cannot be machined square to the 55 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 30.2 kN track before first rotation.", "Ordering discipline for 51111: the catalogue page quotes 51111 and its 30.2/81.5 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51111-SKF?", "a": "Boundary dimensions to ISO 104: bore 55 mm, OD 78 mm, height 16 mm; weight 230 g. Load figures from SKF 17000: dynamic 30.2 kN, static 81.5 kN, fatigue limit 3 kN; reference speed 3,800 r/min (thermal) and limiting speed 5,300 r/min (mechanical)." }, { "q": "What does the designation 51111 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 11 decodes to 55 mm (code 11 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." }, { "q": "Can 51111-SKF carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 55 mm shaft must go to a separate radial bearing; mixed loading through 51111 edge-loads the balls and destroys the washers." } ], "cross_ref": [ { "equiv_sku": "51111", "equiv_brand": "NTN", "level": "partial", "note": "Same 55×78×16 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51111-SKF", "51111" ], "locale_variants": {} }, { "sku": "51211-SKF", "brand": "SKF", "manufacturer_designation": "51211", "series": "51200-series", "type": "thrust_ball", "d_mm": 55, "D_mm": 90, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 58.5, "static_load_kN": 134, "fatigue_load_limit_kN": 4.9, "reference_speed_rpm": 2800, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 590, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51211 is SKF's 55 mm-bore single-direction thrust ball bearing in the 51200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 55×90×25 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 11 encode the bore as 55 mm (code 11 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 55×90×25 mm (2.165×3.543×0.984 in), 17.5 mm radial section, C 58.5 kN, C0 134 kN, Pu 4.9 kN. reference speed 2,800 r/min (thermal) and limiting speed 4,000 r/min (mechanical), catalogue mass 590 g. At the printed limiting speed of 4,000 r/min the mean pitch diameter dm ≈ 72.5 mm implies a dn value around 290k mm·r/min; the 2,800 r/min reference speed is the thermal-planning value under catalogue load. Minimum-load arithmetic: with dm ≈ 72.5 mm and factor A 0.11, Fam ≈ A·(n·dm/1000)² at the 2,800 r/min reference speed is about 4.5 kN for 51211; below that preload the balls skid and smear the tracks. Capacity density: 58.5 kN C from 0.590 kg of bearing steel gives about 99.2 kN per kilogram; static density is correspondingly 227.1 kN/kg at C0 134 kN. Sizing arithmetic on the 55 mm bore: 58.5 kN C over the 17.5 mm radial section gives 3.3 kN per section millimetre, and the 25 mm stack height is 1.43× that section — proportions typical of a 51200 thrust section. Track-circle loading: per millimetre of mean track circumference the 58.5 kN dynamic rating corresponds to roughly 0.26 kN/mm of π·dm track, a useful comparison against the other dimension series of the 55 mm bore. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 25 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 58.5 kN C.", "applications": [ "screw jacks and press-adjustment spindles", "machine-tool adjustment screws and tailstock centres", "vertical pump and motor shaft thrust" ], "failure_modes": [ "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "washer face scoring from swarf trapped between the loose housing washer and its register", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 58.5 kN track before first rotation.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 58.5/134 kN and the available 90 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51211 against two-way load lifts the loose washer off its raceway.", "The 58.5/134 kN figures belong to 51211 specifically (the single flat pressed steel execution of 51211); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51211-SKF?", "a": "51211 measures 55 mm bore × 90 mm OD × 25 mm bearing height (2.165 × 3.543 × 0.984 in), mass about 590 g. SKF 17000 ratings: C 58.5 kN, C0 134 kN, Pu 4.9 kN, reference speed 2,800 r/min (thermal) and limiting speed 4,000 r/min (mechanical)." }, { "q": "What does the designation 51211 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 11 encode the bore as 55 mm (code 11 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can 51211-SKF carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 55 mm shaft must go to a separate radial bearing; mixed loading through 51211 edge-loads the balls and destroys the washers." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." } ], "cross_ref": [ { "equiv_sku": "51211", "equiv_brand": "NTN", "level": "partial", "note": "Same 55×90×25 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51211-SKF", "51211" ], "locale_variants": {} }, { "sku": "51311-SKF", "brand": "SKF", "manufacturer_designation": "51311", "series": "51300-series", "type": "thrust_ball", "d_mm": 55, "D_mm": 105, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 101, "static_load_kN": 224, "fatigue_load_limit_kN": 8.3, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51311 is an ISO 104 single-direction thrust ball bearing, 55 mm bore and 105 mm OD on a flat housing seat, standing 35 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 11: bore 55 mm (code 11 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 55×105×35 mm (2.165×4.134×1.378 in), 25.0 mm radial section, C 101 kN, C0 224 kN, Pu 8.3 kN. reference speed 2,200 r/min (thermal) and limiting speed 3,200 r/min (mechanical), catalogue mass 1300 g. Load balance: C0 224 kN against C 101 kN gives a 2.22 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 8.3 kN enters the adjusted-life check. Speed-ratio note for this exact unit: the reference speed is 2,200 r/min against a 3,200 r/min limiting speed, a reference-to-limit ratio of 0.69. Stack/annulus proportions: the 35 mm axial stack over the 6,283 mm² washer annulus gives 5.57 mm of height per annular square millimetre ×10⁻³, and at 1300 g the bearing holds about 172.3 kN of C0 per kilogram. Pitch-diameter arithmetic: dm = (55+105)/2 = 80.0 mm; at the 3,200 r/min limiting speed that corresponds to roughly 256k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 3,200 r/min while thermal balance under catalogue load sets the 2,200 r/min reference; at dm ≈ 80.0 mm the corresponding dn is approximately 256k mm·r/min. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 35 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 101 kN C.", "applications": [ "screw jacks and press-adjustment spindles", "low-speed reducer thrust positions", "crane hooks and lifting-block pins" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 35 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "The 51311 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 55 mm shaft has to be carried by a radial bearing mounted alongside it.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.26; for 51311 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51311 as the single flat pressed steel execution; other order numbers of the 51311 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51311-SKF?", "a": "The catalogue envelope is 55×105×35 mm, mass 1300 g; ratings C 101 kN / C0 224 kN / Pu 8.3 kN, reference speed 2,200 r/min (thermal) and limiting speed 3,200 r/min (mechanical)." }, { "q": "What does the designation 51311 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 11: bore 55 mm (code 11 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51311-SKF?", "a": "The 2,200 r/min reference speed is the thermal balance under catalogue load; the 3,200 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51311-SKF need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.26 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51311", "equiv_brand": "NTN", "level": "partial", "note": "Same 55×105×35 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51311-SKF", "51311" ], "locale_variants": {} }, { "sku": "51411-SKF", "brand": "SKF", "manufacturer_designation": "51411", "series": "51400-series", "type": "thrust_ball", "d_mm": 55, "D_mm": 120, "B_mm": 48, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 195, "static_load_kN": 400, "fatigue_load_limit_kN": 14.6, "reference_speed_rpm": 1800, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 2550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51411 is SKF's 55 mm-bore single-direction thrust ball bearing in the 51400 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 55×120×48 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 11 encode the bore as 55 mm (code 11 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 55×120×48 mm (2.165×4.724×1.89 in), 32.5 mm radial section, C 195 kN, C0 400 kN, Pu 14.6 kN. reference speed 1,800 r/min (thermal) and limiting speed 2,400 r/min (mechanical), catalogue mass 2550 g. Envelope economics: the 48 mm axial height over a 32.5 mm radial section yields 4.1 kN of dynamic capacity per height millimetre, and the bearing weighs 2550 g for 195 kN C — about 13 g per rated kN. Minimum-load arithmetic: with dm ≈ 87.5 mm and factor A 0.79, Fam ≈ A·(n·dm/1000)² at the 1,800 r/min reference speed is about 19.6 kN for 51411; below that preload the balls skid and smear the tracks. Speed band width for this size is 600 r/min between reference and limiting (1.33× ratio); lubrication, preload and heat removal decide where inside that band 51411 can actually run. Rating split for documentation: dynamic 195 kN (L10 life), static 400 kN (safety factor s0), fatigue limit 14.6 kN (adjusted life) — three different uses of three different numbers for 51411, none interchangeable with another. Light-load floor: Pu = 14.6 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51411; the number is 7 % of the 195 kN dynamic rating. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 48 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 195 kN C.", "applications": [ "machine-tool adjustment screws and tailstock centres", "vertical pump and motor shaft thrust", "screw jacks and press-adjustment spindles" ], "failure_modes": [ "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "track rust staining from condensate during long idle periods in humid plant air", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 195 kN track before first rotation.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 55 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.79; for 51411 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The 195/400 kN figures belong to 51411 specifically (the single flat pressed steel execution of 51411); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51411-SKF?", "a": "51411 measures 55 mm bore × 120 mm OD × 48 mm bearing height (2.165 × 4.724 × 1.89 in), mass about 2550 g. SKF 17000 ratings: C 195 kN, C0 400 kN, Pu 14.6 kN, reference speed 1,800 r/min (thermal) and limiting speed 2,400 r/min (mechanical)." }, { "q": "What does the designation 51411 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 11 encode the bore as 55 mm (code 11 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51411-SKF need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.79 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51411", "equiv_brand": "NTN", "level": "partial", "note": "Same 55×120×48 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51411-SKF", "51411" ], "locale_variants": {} }, { "sku": "51112-SKF", "brand": "SKF", "manufacturer_designation": "51112", "series": "51100-series", "type": "thrust_ball", "d_mm": 60, "D_mm": 85, "B_mm": 17, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 41.6, "static_load_kN": 122, "fatigue_load_limit_kN": 4.55, "reference_speed_rpm": 3600, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 270, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51112 is an ISO 104 single-direction thrust ball bearing, 60 mm bore and 85 mm OD on a flat housing seat, standing 17 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 12: bore 60 mm (code 12 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 60×85×17 mm (2.362×3.346×0.669 in), 12.5 mm radial section, C 41.6 kN, C0 122 kN, Pu 4.55 kN. reference speed 3,600 r/min (thermal) and limiting speed 5,000 r/min (mechanical), catalogue mass 270 g. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.077 at the 5,000 r/min limiting speed raises the required axial preload to about 10.1 kN; the reference-speed value 5.2 kN is the thermal design point. Load balance: C0 122 kN against C 41.6 kN gives a 2.93 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 4.55 kN enters the adjusted-life check. Static-first selection data: 122 kN C0 spread across the 17 mm stack gives 7.2 kN of static rating per height millimetre, and the 270 g mass/C0 ratio is about 2 g per static kN — crane-hook and screw positions are normally sized on these two figures. Rating split for documentation: dynamic 41.6 kN (L10 life), static 122 kN (safety factor s0), fatigue limit 4.55 kN (adjusted life) — three different uses of three different numbers for 51112, none interchangeable with another. Light-load floor: Pu = 4.55 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51112; the number is 11 % of the 41.6 kN dynamic rating. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 60 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 41.6/122 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "vertical motor and pump thrust bearings", "heavy crane hooks and hoist blocks", "winch drums and reducer housings" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "false brinelling of the stationary tracks while the machine stands under vibration", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 60 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.077; for 51112 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The 51112 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 60 mm shaft has to be carried by a radial bearing mounted alongside it.", "When the housing seat cannot be machined square to the 60 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "The 41.6/122 kN figures belong to 51112 specifically (the single flat pressed steel execution of 51112); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51112-SKF?", "a": "The catalogue envelope is 60×85×17 mm, mass 270 g; ratings C 41.6 kN / C0 122 kN / Pu 4.55 kN, reference speed 3,600 r/min (thermal) and limiting speed 5,000 r/min (mechanical)." }, { "q": "What does the designation 51112 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 12: bore 60 mm (code 12 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can 51112-SKF carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 60 mm shaft must go to a separate radial bearing; mixed loading through 51112 edge-loads the balls and destroys the washers." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." } ], "cross_ref": [ { "equiv_sku": "51112", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51112-SKF", "51112" ], "locale_variants": {} }, { "sku": "51212-SKF", "brand": "SKF", "manufacturer_designation": "51212", "series": "51200-series", "type": "thrust_ball", "d_mm": 60, "D_mm": 95, "B_mm": 26, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 59.2, "static_load_kN": 140, "fatigue_load_limit_kN": 5.1, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51212 is SKF's 60 mm-bore single-direction thrust ball bearing in the 51200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 60×95×26 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 12 encode the bore as 60 mm (code 12 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 60×95×26 mm (2.362×3.74×1.024 in), 17.5 mm radial section, C 59.2 kN, C0 140 kN, Pu 5.1 kN. reference speed 2,800 r/min (thermal) and limiting speed 3,800 r/min (mechanical), catalogue mass 650 g. Load balance: C0 140 kN against C 59.2 kN gives a 2.36 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 5.1 kN enters the adjusted-life check. Selection figures for 51212: the C0/C ratio is 2.36, Pu 5.1 kN is about 9 % of C, and the catalogue mass works out to roughly 11 g per millimetre of bore; the printed minimum-load factor is A 0.12. Light-load floor: Pu = 5.1 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51212; the number is 9 % of the 59.2 kN dynamic rating. Mass and section check: 650 g inside the 60×95×26 mm outline leaves a 17.5 mm radial section, and the 140 kN static rating is 2.36× the dynamic rating — plan static safety and minimum preload against those figures. Envelope economics: the 26 mm axial height over a 17.5 mm radial section yields 2.3 kN of dynamic capacity per height millimetre, and the bearing weighs 650 g for 59.2 kN C — about 11 g per rated kN. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 26 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 59.2 kN C.", "applications": [ "heavy crane hooks and hoist blocks", "large screw jacks and press rams", "turret and slewing-bearing adjustment screws" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "track rust staining from condensate during long idle periods in humid plant air" ], "pitfalls": [ "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51212 against two-way load lifts the loose washer off its raceway.", "When the housing seat cannot be machined square to the 60 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 60 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51212 as the single flat pressed steel execution; other order numbers of the 51212 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51212-SKF?", "a": "51212 measures 60 mm bore × 95 mm OD × 26 mm bearing height (2.362 × 3.74 × 1.024 in), mass about 650 g. SKF 17000 ratings: C 59.2 kN, C0 140 kN, Pu 5.1 kN, reference speed 2,800 r/min (thermal) and limiting speed 3,800 r/min (mechanical)." }, { "q": "What does the designation 51212 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 12 encode the bore as 60 mm (code 12 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." }, { "q": "Can 51212-SKF carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 60 mm shaft must go to a separate radial bearing; mixed loading through 51212 edge-loads the balls and destroys the washers." } ], "cross_ref": [ { "equiv_sku": "51212", "equiv_brand": "NTN", "level": "partial", "note": "Same 60×95×26 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51212-SKF", "51212" ], "locale_variants": {} }, { "sku": "51312-SKF", "brand": "SKF", "manufacturer_designation": "51312", "series": "51300-series", "type": "thrust_ball", "d_mm": 60, "D_mm": 110, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 101, "static_load_kN": 224, "fatigue_load_limit_kN": 8.3, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51300 series order number 51312 is a SKF single-direction thrust ball bearing for a 60 mm seat, built to ISO 104, with a flat housing seating surface, 60×110×35 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 12 decodes to 60 mm (code 12 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 60×110×35 mm (2.362×4.331×1.378 in), 25.0 mm radial section, C 101 kN, C0 224 kN, Pu 8.3 kN. reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical), catalogue mass 1350 g. Track-circle loading: per millimetre of mean track circumference the 101 kN dynamic rating corresponds to roughly 0.38 kN/mm of π·dm track, a useful comparison against the other dimension series of the 60 mm bore. Pitch-diameter arithmetic: dm = (60+110)/2 = 85.0 mm; at the 3,000 r/min limiting speed that corresponds to roughly 255k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Mass and section check: 1350 g inside the 60×110×35 mm outline leaves a 25.0 mm radial section, and the 224 kN static rating is 2.22× the dynamic rating — plan static safety and minimum preload against those figures. Load balance: C0 224 kN against C 101 kN gives a 2.22 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 8.3 kN enters the adjusted-life check. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51312 covers about 6,676 mm², distributing C0 224 kN over a mean track circle of π·dm ≈ 267 mm. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 35 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 101 kN C.", "applications": [ "turret and slewing-bearing adjustment screws", "large screw jacks and press rams", "vertical motor and pump thrust bearings" ], "failure_modes": [ "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "washer face scoring from swarf trapped between the loose housing washer and its register", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "The 51312 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 60 mm shaft has to be carried by a radial bearing mounted alongside it.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 101 kN track before first rotation.", "When the housing seat cannot be machined square to the 60 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51300 bearing.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 35 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51312 as the single flat pressed steel execution; other order numbers of the 51312 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51312-SKF?", "a": "Boundary dimensions to ISO 104: bore 60 mm, OD 110 mm, height 35 mm; weight 1350 g. Load figures from SKF 17000: dynamic 101 kN, static 224 kN, fatigue limit 8.3 kN; reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical)." }, { "q": "What does the designation 51312 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 12 decodes to 60 mm (code 12 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51312-SKF lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 3,000 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 60 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51312", "equiv_brand": "NTN", "level": "partial", "note": "Same 60×110×35 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51312-SKF", "51312" ], "locale_variants": {} }, { "sku": "51412-M", "brand": "SKF", "manufacturer_designation": "51412 M", "series": "51400-series", "type": "thrust_ball", "d_mm": 60, "D_mm": 130, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 199, "static_load_kN": 430, "fatigue_load_limit_kN": 16, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 3100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51400 series order number 51412 M is a SKF single-direction thrust ball bearing for a 60 mm seat, built to ISO 104, with a flat housing seating surface, 60×130×51 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 12 decodes to 60 mm (code 12 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 60×130×51 mm (2.362×5.118×2.008 in), 35.0 mm radial section, C 199 kN, C0 430 kN, Pu 16 kN. reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical), catalogue mass 3100 g. Load balance: C0 430 kN against C 199 kN gives a 2.16 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 16 kN enters the adjusted-life check. Envelope economics: the 51 mm axial height over a 35.0 mm radial section yields 3.9 kN of dynamic capacity per height millimetre, and the bearing weighs 3100 g for 199 kN C — about 16 g per rated kN. Sizing arithmetic on the 60 mm bore: 199 kN C over the 35.0 mm radial section gives 5.7 kN per section millimetre, and the 51 mm stack height is 1.46× that section — proportions typical of a 51400 thrust section. Speed band width for this size is 600 r/min between reference and limiting (1.38× ratio); lubrication, preload and heat removal decide where inside that band 51412 M can actually run. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51412 M covers about 10,446 mm², distributing C0 430 kN over a mean track circle of π·dm ≈ 298 mm. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 3100 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 60 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "heavy crane hooks and hoist blocks", "winch drums and reducer housings", "turret and slewing-bearing adjustment screws" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "When the housing seat cannot be machined square to the 60 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51400 bearing.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 60 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 51 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Ordering discipline for 51412: the catalogue page quotes 51412 M and its 199/430 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51412-M?", "a": "Boundary dimensions to ISO 104: bore 60 mm, OD 130 mm, height 51 mm; weight 3100 g. Load figures from SKF 17000: dynamic 199 kN, static 430 kN, fatigue limit 16 kN; reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical)." }, { "q": "What does the designation 51412 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 12 decodes to 60 mm (code 12 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 60 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51412 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51412", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51412-M", "51412 M" ], "locale_variants": {} }, { "sku": "51113-SKF", "brand": "SKF", "manufacturer_designation": "51113", "series": "51100-series", "type": "thrust_ball", "d_mm": 65, "D_mm": 90, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 37.7, "static_load_kN": 108, "fatigue_load_limit_kN": 4, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 330, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51113 is a SKF single-direction thrust ball bearing for a 65 mm seat, built to ISO 104, with a flat housing seating surface, 65×90×18 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 13 decodes to 65 mm (code 13 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 65×90×18 mm (2.559×3.543×0.709 in), 12.5 mm radial section, C 37.7 kN, C0 108 kN, Pu 4 kN. reference speed 3,400 r/min (thermal) and limiting speed 4,800 r/min (mechanical), catalogue mass 330 g. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51113 covers about 3,043 mm², distributing C0 108 kN over a mean track circle of π·dm ≈ 243 mm. Envelope economics: the 18 mm axial height over a 12.5 mm radial section yields 2.1 kN of dynamic capacity per height millimetre, and the bearing weighs 330 g for 37.7 kN C — about 9 g per rated kN. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 4,800 r/min while thermal balance under catalogue load sets the 3,400 r/min reference; at dm ≈ 77.5 mm the corresponding dn is approximately 372k mm·r/min. Load balance: C0 108 kN against C 37.7 kN gives a 2.86 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 4 kN enters the adjusted-life check. Bore-to-OD planning: OD 90 over bore 65 is a 1.38× step for this size, and the 18 mm height gives a bore/height ratio of 3.61; use these ratios when the housing recess around the 65 mm shaft is the first constraint. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 65 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 37.7/108 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "heavy crane hooks and hoist blocks", "winch drums and reducer housings", "large screw jacks and press rams" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "The 51113 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 65 mm shaft has to be carried by a radial bearing mounted alongside it.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 37.7/108 kN and the available 90 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "When the housing seat cannot be machined square to the 65 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51113 as the single flat pressed steel execution; other order numbers of the 51113 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51113-SKF?", "a": "Boundary dimensions to ISO 104: bore 65 mm, OD 90 mm, height 18 mm; weight 330 g. Load figures from SKF 17000: dynamic 37.7 kN, static 108 kN, fatigue limit 4 kN; reference speed 3,400 r/min (thermal) and limiting speed 4,800 r/min (mechanical)." }, { "q": "What does the designation 51113 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 13 decodes to 65 mm (code 13 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." }, { "q": "How is 51113-SKF lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 4,800 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "51113", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51113-SKF", "51113" ], "locale_variants": {} }, { "sku": "51213-SKF", "brand": "SKF", "manufacturer_designation": "51213", "series": "51200-series", "type": "thrust_ball", "d_mm": 65, "D_mm": 100, "B_mm": 27, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 60.5, "static_load_kN": 150, "fatigue_load_limit_kN": 5.5, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 720, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51200 series order number 51213 is a SKF single-direction thrust ball bearing for a 65 mm seat, built to ISO 104, with a flat housing seating surface, 65×100×27 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 13 decodes to 65 mm (code 13 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 65×100×27 mm (2.559×3.937×1.063 in), 17.5 mm radial section, C 60.5 kN, C0 150 kN, Pu 5.5 kN. reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical), catalogue mass 720 g. Speed band width for this size is 1,000 r/min between reference and limiting (1.38× ratio); lubrication, preload and heat removal decide where inside that band 51213 can actually run. Capacity density: 60.5 kN C from 0.720 kg of bearing steel gives about 84.0 kN per kilogram; static density is correspondingly 208.3 kN/kg at C0 150 kN. Selection figures for 51213: the C0/C ratio is 2.48, Pu 5.5 kN is about 9 % of C, and the catalogue mass works out to roughly 11 g per millimetre of bore; the printed minimum-load factor is A 0.14. Sizing arithmetic on the 65 mm bore: 60.5 kN C over the 17.5 mm radial section gives 3.5 kN per section millimetre, and the 27 mm stack height is 1.54× that section — proportions typical of a 51200 thrust section. Light-load floor: Pu = 5.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51213; the number is 9 % of the 60.5 kN dynamic rating. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 65 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 60.5/150 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "turret and slewing-bearing adjustment screws", "large screw jacks and press rams", "vertical motor and pump thrust bearings" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "track rust staining from condensate during long idle periods in humid plant air", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 27 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The 51213 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 65 mm shaft has to be carried by a radial bearing mounted alongside it.", "When the housing seat cannot be machined square to the 65 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 60.5/150 kN and the available 100 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51213 as the single flat pressed steel execution; other order numbers of the 51213 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51213-SKF?", "a": "Boundary dimensions to ISO 104: bore 65 mm, OD 100 mm, height 27 mm; weight 720 g. Load figures from SKF 17000: dynamic 60.5 kN, static 150 kN, fatigue limit 5.5 kN; reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical)." }, { "q": "What does the designation 51213 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 13 decodes to 65 mm (code 13 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51213-SKF need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.14 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51213", "equiv_brand": "NTN", "level": "partial", "note": "Same 65×100×27 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51213-SKF", "51213" ], "locale_variants": {} }, { "sku": "51313-SKF", "brand": "SKF", "manufacturer_designation": "51313", "series": "51300-series", "type": "thrust_ball", "d_mm": 65, "D_mm": 115, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 106, "static_load_kN": 240, "fatigue_load_limit_kN": 8.8, "reference_speed_rpm": 2000, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51313 is SKF's 65 mm-bore single-direction thrust ball bearing in the 51300 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 65×115×36 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 13 encode the bore as 65 mm (code 13 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 65×115×36 mm (2.559×4.528×1.417 in), 25.0 mm radial section, C 106 kN, C0 240 kN, Pu 8.8 kN. reference speed 2,000 r/min (thermal) and limiting speed 3,000 r/min (mechanical), catalogue mass 1500 g. Bore-to-OD planning: OD 115 over bore 65 is a 1.77× step for this size, and the 36 mm height gives a bore/height ratio of 1.81; use these ratios when the housing recess around the 65 mm shaft is the first constraint. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51313 covers about 7,069 mm², distributing C0 240 kN over a mean track circle of π·dm ≈ 283 mm. Load balance: C0 240 kN against C 106 kN gives a 2.26 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 8.8 kN enters the adjusted-life check. Selection figures for 51313: the C0/C ratio is 2.26, Pu 8.8 kN is about 8 % of C, and the catalogue mass works out to roughly 23 g per millimetre of bore; the printed minimum-load factor is A 0.3. Mass and section check: 1500 g inside the 65×115×36 mm outline leaves a 25.0 mm radial section, and the 240 kN static rating is 2.26× the dynamic rating — plan static safety and minimum preload against those figures. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 65 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 106/240 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "winch drums and reducer housings", "vertical motor and pump thrust bearings", "large screw jacks and press rams" ], "failure_modes": [ "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 106 kN track before first rotation.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 65 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 106/240 kN and the available 115 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The 106/240 kN figures belong to 51313 specifically (the single flat pressed steel execution of 51313); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51313-SKF?", "a": "51313 measures 65 mm bore × 115 mm OD × 36 mm bearing height (2.559 × 4.528 × 1.417 in), mass about 1500 g. SKF 17000 ratings: C 106 kN, C0 240 kN, Pu 8.8 kN, reference speed 2,000 r/min (thermal) and limiting speed 3,000 r/min (mechanical)." }, { "q": "What does the designation 51313 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 13 encode the bore as 65 mm (code 13 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 65 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51313 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51313", "equiv_brand": "NTN", "level": "partial", "note": "Same 65×115×36 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51313-SKF", "51313" ], "locale_variants": {} }, { "sku": "51413-M", "brand": "SKF", "manufacturer_designation": "51413 M", "series": "51400-series", "type": "thrust_ball", "d_mm": 65, "D_mm": 140, "B_mm": 56, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 216, "static_load_kN": 490, "fatigue_load_limit_kN": 18, "reference_speed_rpm": 1500, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 4000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51400 series order number 51413 M is a SKF single-direction thrust ball bearing for a 65 mm seat, built to ISO 104, with a flat housing seating surface, 65×140×56 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 13 decodes to 65 mm (code 13 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 65×140×56 mm (2.559×5.512×2.205 in), 37.5 mm radial section, C 216 kN, C0 490 kN, Pu 18 kN. reference speed 1,500 r/min (thermal) and limiting speed 2,200 r/min (mechanical), catalogue mass 4000 g. Mass and section check: 4000 g inside the 65×140×56 mm outline leaves a 37.5 mm radial section, and the 490 kN static rating is 2.27× the dynamic rating — plan static safety and minimum preload against those figures. Stack/annulus proportions: the 56 mm axial stack over the 12,075 mm² washer annulus gives 4.64 mm of height per annular square millimetre ×10⁻³, and at 4000 g the bearing holds about 122.5 kN of C0 per kilogram. Section proportions: the 37.5 mm radial section compares with 65 mm of bore (section/bore ≈ 0.58) and the 56 mm height is 1.49× that section — the proportions that identify the 51400 envelope at a glance. Sizing arithmetic on the 65 mm bore: 216 kN C over the 37.5 mm radial section gives 5.8 kN per section millimetre, and the 56 mm stack height is 1.49× that section — proportions typical of a 51400 thrust section. Rating split for documentation: dynamic 216 kN (L10 life), static 490 kN (safety factor s0), fatigue limit 18 kN (adjusted life) — three different uses of three different numbers for 51413 M, none interchangeable with another. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51413 M adds a small amount of mass and cage strength without changing the 65×140×56 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 2,200 r/min ceiling.", "applications": [ "vertical motor and pump thrust bearings", "heavy crane hooks and hoist blocks", "winch drums and reducer housings" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "false brinelling of the stationary tracks while the machine stands under vibration", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The 51413 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 65 mm shaft has to be carried by a radial bearing mounted alongside it.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 216/490 kN and the available 140 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "When the housing seat cannot be machined square to the 65 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51400 bearing.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51413 M as the single flat brass execution; other order numbers of the 51413 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51413-M?", "a": "Boundary dimensions to ISO 104: bore 65 mm, OD 140 mm, height 56 mm; weight 4000 g. Load figures from SKF 17000: dynamic 216 kN, static 490 kN, fatigue limit 18 kN; reference speed 1,500 r/min (thermal) and limiting speed 2,200 r/min (mechanical)." }, { "q": "What does the designation 51413 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 13 decodes to 65 mm (code 13 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51413-M need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 1.2 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number is a different, M-cage product) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51413", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51413-M", "51413 M" ], "locale_variants": {} }, { "sku": "51114-SKF", "brand": "SKF", "manufacturer_designation": "51114", "series": "51100-series", "type": "thrust_ball", "d_mm": 70, "D_mm": 95, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 40.3, "static_load_kN": 120, "fatigue_load_limit_kN": 4.4, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4500, "max_rpm": 4500, "weight_g": 350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51114 is a SKF single-direction thrust ball bearing for a 70 mm seat, built to ISO 104, with a flat housing seating surface, 70×95×18 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 14 decodes to 70 mm (code 14 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 70×95×18 mm (2.756×3.74×0.709 in), 12.5 mm radial section, C 40.3 kN, C0 120 kN, Pu 4.4 kN. reference speed 3,400 r/min (thermal) and limiting speed 4,500 r/min (mechanical), catalogue mass 350 g. Stack/annulus proportions: the 18 mm axial stack over the 3,240 mm² washer annulus gives 5.56 mm of height per annular square millimetre ×10⁻³, and at 350 g the bearing holds about 342.9 kN of C0 per kilogram. Pitch-diameter arithmetic: dm = (70+95)/2 = 82.5 mm; at the 4,500 r/min limiting speed that corresponds to roughly 371k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. At the printed limiting speed of 4,500 r/min the mean pitch diameter dm ≈ 82.5 mm implies a dn value around 371k mm·r/min; the 3,400 r/min reference speed is the thermal-planning value under catalogue load. Sizing arithmetic on the 70 mm bore: 40.3 kN C over the 12.5 mm radial section gives 3.2 kN per section millimetre, and the 18 mm stack height is 1.44× that section — proportions typical of a 51100 thrust section. Load balance: C0 120 kN against C 40.3 kN gives a 2.98 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 4.4 kN enters the adjusted-life check. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 70 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 40.3/120 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "vertical motor and pump thrust bearings", "heavy crane hooks and hoist blocks", "large screw jacks and press rams" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "false brinelling of the stationary tracks while the machine stands under vibration", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 70 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.074; for 51114 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "When the housing seat cannot be machined square to the 70 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 18 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The 40.3/120 kN figures belong to 51114 specifically (the single flat pressed steel execution of 51114); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51114-SKF?", "a": "Boundary dimensions to ISO 104: bore 70 mm, OD 95 mm, height 18 mm; weight 350 g. Load figures from SKF 17000: dynamic 40.3 kN, static 120 kN, fatigue limit 4.4 kN; reference speed 3,400 r/min (thermal) and limiting speed 4,500 r/min (mechanical)." }, { "q": "What does the designation 51114 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 14 decodes to 70 mm (code 14 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51114-SKF lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 4,500 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 70 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51114", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51114-SKF", "51114" ], "locale_variants": {} }, { "sku": "51214-SKF", "brand": "SKF", "manufacturer_designation": "51214", "series": "51200-series", "type": "thrust_ball", "d_mm": 70, "D_mm": 105, "B_mm": 27, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 62.4, "static_load_kN": 160, "fatigue_load_limit_kN": 5.85, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 790, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51200 series order number 51214 is a SKF single-direction thrust ball bearing for a 70 mm seat, built to ISO 104, with a flat housing seating surface, 70×105×27 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 14 decodes to 70 mm (code 14 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 70×105×27 mm (2.756×4.134×1.063 in), 17.5 mm radial section, C 62.4 kN, C0 160 kN, Pu 5.85 kN. reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical), catalogue mass 790 g. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51214 covers about 4,811 mm², distributing C0 160 kN over a mean track circle of π·dm ≈ 275 mm. Track-circle loading: per millimetre of mean track circumference the 62.4 kN dynamic rating corresponds to roughly 0.23 kN/mm of π·dm track, a useful comparison against the other dimension series of the 70 mm bore. Bore-to-OD planning: OD 105 over bore 70 is a 1.50× step for this size, and the 27 mm height gives a bore/height ratio of 2.59; use these ratios when the housing recess around the 70 mm shaft is the first constraint. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.16 at the 3,600 r/min limiting speed raises the required axial preload to about 15.9 kN; the reference-speed value 8.3 kN is the thermal design point. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 3,600 r/min while thermal balance under catalogue load sets the 2,600 r/min reference; at dm ≈ 87.5 mm the corresponding dn is approximately 315k mm·r/min. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 70 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 62.4/160 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "large screw jacks and press rams", "winch drums and reducer housings", "turret and slewing-bearing adjustment screws" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "false brinelling of the stationary tracks while the machine stands under vibration" ], "pitfalls": [ "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51214 against two-way load lifts the loose washer off its raceway.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.16; for 51214 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 62.4/160 kN and the available 105 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51214 as the single flat pressed steel execution; other order numbers of the 51214 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51214-SKF?", "a": "Boundary dimensions to ISO 104: bore 70 mm, OD 105 mm, height 27 mm; weight 790 g. Load figures from SKF 17000: dynamic 62.4 kN, static 160 kN, fatigue limit 5.85 kN; reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical)." }, { "q": "What does the designation 51214 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 14 decodes to 70 mm (code 14 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51214-SKF?", "a": "The 2,600 r/min reference speed is the thermal balance under catalogue load; the 3,600 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51214-SKF need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.16 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51214", "equiv_brand": "NTN", "level": "partial", "note": "Same 70×105×27 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "53214", "equiv_brand": "SKF", "level": "full", "note": "Same 70×105×27 mm ISO 104 thrust-ball envelope with catalogue ratings within 10 %; 53214 is the single-direction, sphered housing washer with U 214 seat washer, stamped sheet-steel cage execution of this size — boundary dimensions interchangeable, execution differs. The counterpart is a sphered execution that needs its U 214 seat washer; its mounted H1 is taller than the bearing height." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51214-SKF", "51214" ], "locale_variants": {} }, { "sku": "51314-SKF", "brand": "SKF", "manufacturer_designation": "51314", "series": "51300-series", "type": "thrust_ball", "d_mm": 70, "D_mm": 125, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 135, "static_load_kN": 320, "fatigue_load_limit_kN": 11.8, "reference_speed_rpm": 1900, "limiting_speed_rpm": 2600, "max_rpm": 2600, "weight_g": 2000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51300 series order number 51314 is a SKF single-direction thrust ball bearing for a 70 mm seat, built to ISO 104, with a flat housing seating surface, 70×125×40 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 14 decodes to 70 mm (code 14 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 70×125×40 mm (2.756×4.921×1.575 in), 27.5 mm radial section, C 135 kN, C0 320 kN, Pu 11.8 kN. reference speed 1,900 r/min (thermal) and limiting speed 2,600 r/min (mechanical), catalogue mass 2000 g. Bore-to-OD planning: OD 125 over bore 70 is a 1.79× step for this size, and the 40 mm height gives a bore/height ratio of 1.75; use these ratios when the housing recess around the 70 mm shaft is the first constraint. Light-load floor: Pu = 11.8 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51314; the number is 9 % of the 135 kN dynamic rating. Pitch-diameter arithmetic: dm = (70+125)/2 = 97.5 mm; at the 2,600 r/min limiting speed that corresponds to roughly 254k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Capacity density: 135 kN C from 2.000 kg of bearing steel gives about 67.5 kN per kilogram; static density is correspondingly 160.0 kN/kg at C0 320 kN. Stack/annulus proportions: the 40 mm axial stack over the 8,423 mm² washer annulus gives 4.75 mm of height per annular square millimetre ×10⁻³, and at 2000 g the bearing holds about 160.0 kN of C0 per kilogram. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 40 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 135 kN C.", "applications": [ "large screw jacks and press rams", "vertical motor and pump thrust bearings", "turret and slewing-bearing adjustment screws" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "cage damage from mounting force applied through the balls instead of the washer face", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 135 kN track before first rotation.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 40 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "When the housing seat cannot be machined square to the 70 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51300 bearing.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51314 against two-way load lifts the loose washer off its raceway.", "The 135/320 kN figures belong to 51314 specifically (the single flat pressed steel execution of 51314); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51314-SKF?", "a": "Boundary dimensions to ISO 104: bore 70 mm, OD 125 mm, height 40 mm; weight 2000 g. Load figures from SKF 17000: dynamic 135 kN, static 320 kN, fatigue limit 11.8 kN; reference speed 1,900 r/min (thermal) and limiting speed 2,600 r/min (mechanical)." }, { "q": "What does the designation 51314 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 14 decodes to 70 mm (code 14 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can 51314-SKF carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 70 mm shaft must go to a separate radial bearing; mixed loading through 51314 edge-loads the balls and destroys the washers." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." } ], "cross_ref": [ { "equiv_sku": "51314", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51314-SKF", "51314" ], "locale_variants": {} }, { "sku": "51414-M", "brand": "SKF", "manufacturer_designation": "51414 M", "series": "51400-series", "type": "thrust_ball", "d_mm": 70, "D_mm": 150, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 234, "static_load_kN": 550, "fatigue_load_limit_kN": 19.3, "reference_speed_rpm": 1400, "limiting_speed_rpm": 2000, "max_rpm": 2000, "weight_g": 5000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51400 series order number 51414 M is a SKF single-direction thrust ball bearing for a 70 mm seat, built to ISO 104, with a flat housing seating surface, 70×150×60 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 14 decodes to 70 mm (code 14 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 70×150×60 mm (2.756×5.906×2.362 in), 40.0 mm radial section, C 234 kN, C0 550 kN, Pu 19.3 kN. reference speed 1,400 r/min (thermal) and limiting speed 2,000 r/min (mechanical), catalogue mass 5000 g. Track-circle loading: per millimetre of mean track circumference the 234 kN dynamic rating corresponds to roughly 0.68 kN/mm of π·dm track, a useful comparison against the other dimension series of the 70 mm bore. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51414 M covers about 13,823 mm², distributing C0 550 kN over a mean track circle of π·dm ≈ 346 mm. Section proportions: the 40.0 mm radial section compares with 70 mm of bore (section/bore ≈ 0.57) and the 60 mm height is 1.50× that section — the proportions that identify the 51400 envelope at a glance. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 1.6 at the 2,000 r/min limiting speed raises the required axial preload to about 77.4 kN; the reference-speed value 37.9 kN is the thermal design point. Speed band width for this size is 600 r/min between reference and limiting (1.43× ratio); lubrication, preload and heat removal decide where inside that band 51414 M can actually run. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51414 M adds a small amount of mass and cage strength without changing the 70×150×60 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 2,000 r/min ceiling.", "applications": [ "turret and slewing-bearing adjustment screws", "large screw jacks and press rams", "heavy crane hooks and hoist blocks" ], "failure_modes": [ "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "washer face scoring from swarf trapped between the loose housing washer and its register" ], "pitfalls": [ "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 70 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 1.6; for 51414 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "When the housing seat cannot be machined square to the 70 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51400 bearing.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 60 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The 234/550 kN figures belong to 51414 M specifically (the single flat brass execution of 51414); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51414-M?", "a": "Boundary dimensions to ISO 104: bore 70 mm, OD 150 mm, height 60 mm; weight 5000 g. Load figures from SKF 17000: dynamic 234 kN, static 550 kN, fatigue limit 19.3 kN; reference speed 1,400 r/min (thermal) and limiting speed 2,000 r/min (mechanical)." }, { "q": "What does the designation 51414 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 14 decodes to 70 mm (code 14 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." }, { "q": "How is 51414-M lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 2,000 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "51414", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51414-M", "51414 M" ], "locale_variants": {} }, { "sku": "51115-SKF", "brand": "SKF", "manufacturer_designation": "51115", "series": "51100-series", "type": "thrust_ball", "d_mm": 75, "D_mm": 100, "B_mm": 19, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 44.2, "static_load_kN": 134, "fatigue_load_limit_kN": 4.9, "reference_speed_rpm": 3200, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51115 is an ISO 104 single-direction thrust ball bearing, 75 mm bore and 100 mm OD on a flat housing seat, standing 19 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 15: bore 75 mm (code 15 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 75×100×19 mm (2.953×3.937×0.748 in), 12.5 mm radial section, C 44.2 kN, C0 134 kN, Pu 4.9 kN. reference speed 3,200 r/min (thermal) and limiting speed 4,300 r/min (mechanical), catalogue mass 400 g. Load balance: C0 134 kN against C 44.2 kN gives a 3.03 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 4.9 kN enters the adjusted-life check. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 4,300 r/min while thermal balance under catalogue load sets the 3,200 r/min reference; at dm ≈ 87.5 mm the corresponding dn is approximately 376k mm·r/min. Capacity density: 44.2 kN C from 0.400 kg of bearing steel gives about 110.5 kN per kilogram; static density is correspondingly 335.0 kN/kg at C0 134 kN. Mass and section check: 400 g inside the 75×100×19 mm outline leaves a 12.5 mm radial section, and the 134 kN static rating is 3.03× the dynamic rating — plan static safety and minimum preload against those figures. Envelope economics: the 19 mm axial height over a 12.5 mm radial section yields 2.3 kN of dynamic capacity per height millimetre, and the bearing weighs 400 g for 44.2 kN C — about 9 g per rated kN. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 19 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 44.2 kN C.", "applications": [ "vertical motor and pump thrust bearings", "turret and slewing-bearing adjustment screws", "winch drums and reducer housings" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "pitting on one track sector from a perpetually eccentric thrust line", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 19 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 44.2 kN track before first rotation.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.11; for 51115 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The 44.2/134 kN figures belong to 51115 specifically (the single flat pressed steel execution of 51115); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51115-SKF?", "a": "The catalogue envelope is 75×100×19 mm, mass 400 g; ratings C 44.2 kN / C0 134 kN / Pu 4.9 kN, reference speed 3,200 r/min (thermal) and limiting speed 4,300 r/min (mechanical)." }, { "q": "What does the designation 51115 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 15: bore 75 mm (code 15 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 75 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51115 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51115", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51115-SKF", "51115" ], "locale_variants": {} }, { "sku": "51215-SKF", "brand": "SKF", "manufacturer_designation": "51215", "series": "51200-series", "type": "thrust_ball", "d_mm": 75, "D_mm": 110, "B_mm": 27, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 63.7, "static_load_kN": 170, "fatigue_load_limit_kN": 6.2, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 830, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51215 is an ISO 104 single-direction thrust ball bearing, 75 mm bore and 110 mm OD on a flat housing seat, standing 27 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 15: bore 75 mm (code 15 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 75×110×27 mm (2.953×4.331×1.063 in), 17.5 mm radial section, C 63.7 kN, C0 170 kN, Pu 6.2 kN. reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical), catalogue mass 830 g. Envelope economics: the 27 mm axial height over a 17.5 mm radial section yields 2.4 kN of dynamic capacity per height millimetre, and the bearing weighs 830 g for 63.7 kN C — about 13 g per rated kN. Mass and section check: 830 g inside the 75×110×27 mm outline leaves a 17.5 mm radial section, and the 170 kN static rating is 2.67× the dynamic rating — plan static safety and minimum preload against those figures. Pitch-diameter arithmetic: dm = (75+110)/2 = 92.5 mm; at the 3,400 r/min limiting speed that corresponds to roughly 315k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Load balance: C0 170 kN against C 63.7 kN gives a 2.67 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 6.2 kN enters the adjusted-life check. Bore-to-OD planning: OD 110 over bore 75 is a 1.47× step for this size, and the 27 mm height gives a bore/height ratio of 2.78; use these ratios when the housing recess around the 75 mm shaft is the first constraint. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 27 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 63.7 kN C.", "applications": [ "winch drums and reducer housings", "vertical motor and pump thrust bearings", "large screw jacks and press rams" ], "failure_modes": [ "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "cage damage from mounting force applied through the balls instead of the washer face", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "When the housing seat cannot be machined square to the 75 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 63.7 kN track before first rotation.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 27 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 63.7/170 kN and the available 110 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Ordering discipline for 51215: the catalogue page quotes 51215 and its 63.7/170 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51215-SKF?", "a": "The catalogue envelope is 75×110×27 mm, mass 830 g; ratings C 63.7 kN / C0 170 kN / Pu 6.2 kN, reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical)." }, { "q": "What does the designation 51215 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 15: bore 75 mm (code 15 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can a single 51215 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." }, { "q": "What do the two published speeds mean for 51215-SKF?", "a": "The 2,400 r/min reference speed is the thermal balance under catalogue load; the 3,400 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." } ], "cross_ref": [ { "equiv_sku": "51215", "equiv_brand": "NTN", "level": "partial", "note": "Same 75×110×27 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51215-SKF", "51215" ], "locale_variants": {} }, { "sku": "51315-SKF", "brand": "SKF", "manufacturer_designation": "51315", "series": "51300-series", "type": "thrust_ball", "d_mm": 75, "D_mm": 135, "B_mm": 44, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 163, "static_load_kN": 390, "fatigue_load_limit_kN": 14, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 2600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51315 is an ISO 104 single-direction thrust ball bearing, 75 mm bore and 135 mm OD on a flat housing seat, standing 44 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 15: bore 75 mm (code 15 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 75×135×44 mm (2.953×5.315×1.732 in), 30.0 mm radial section, C 163 kN, C0 390 kN, Pu 14 kN. reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical), catalogue mass 2600 g. Light-load floor: Pu = 14 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51315; the number is 9 % of the 163 kN dynamic rating. Section proportions: the 30.0 mm radial section compares with 75 mm of bore (section/bore ≈ 0.40) and the 44 mm height is 1.47× that section — the proportions that identify the 51300 envelope at a glance. Sizing arithmetic on the 75 mm bore: 163 kN C over the 30.0 mm radial section gives 5.4 kN per section millimetre, and the 44 mm stack height is 1.47× that section — proportions typical of a 51300 thrust section. Speed-ratio note for this exact unit: the reference speed is 1,700 r/min against a 2,400 r/min limiting speed, a reference-to-limit ratio of 0.71. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.79 at the 2,400 r/min limiting speed raises the required axial preload to about 50.2 kN; the reference-speed value 25.2 kN is the thermal design point. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 44 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 163 kN C.", "applications": [ "winch drums and reducer housings", "large screw jacks and press rams", "turret and slewing-bearing adjustment screws" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.79; for 51315 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51315 against two-way load lifts the loose washer off its raceway.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 44 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Ordering discipline for 51315: the catalogue page quotes 51315 and its 163/390 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51315-SKF?", "a": "The catalogue envelope is 75×135×44 mm, mass 2600 g; ratings C 163 kN / C0 390 kN / Pu 14 kN, reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical)." }, { "q": "What does the designation 51315 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 15: bore 75 mm (code 15 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." }, { "q": "How is 51315-SKF lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 2,400 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "51315", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51315-SKF", "51315" ], "locale_variants": {} }, { "sku": "51415-M", "brand": "SKF", "manufacturer_designation": "51415 M", "series": "51400-series", "type": "thrust_ball", "d_mm": 75, "D_mm": 160, "B_mm": 65, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 251, "static_load_kN": 610, "fatigue_load_limit_kN": 20.8, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 6750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51415 M is SKF's 75 mm-bore single-direction thrust ball bearing in the 51400 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 75×160×65 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 15 encode the bore as 75 mm (code 15 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 75×160×65 mm (2.953×6.299×2.559 in), 42.5 mm radial section, C 251 kN, C0 610 kN, Pu 20.8 kN. reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical), catalogue mass 6750 g. Sizing arithmetic on the 75 mm bore: 251 kN C over the 42.5 mm radial section gives 5.9 kN per section millimetre, and the 65 mm stack height is 1.53× that section — proportions typical of a 51400 thrust section. Stack/annulus proportions: the 65 mm axial stack over the 15,688 mm² washer annulus gives 4.14 mm of height per annular square millimetre ×10⁻³, and at 6750 g the bearing holds about 90.4 kN of C0 per kilogram. Speed planning separates the two ceilings mechanically: the pressed brass cage and balls tolerate 1,800 r/min while thermal balance under catalogue load sets the 1,300 r/min reference; at dm ≈ 117.5 mm the corresponding dn is approximately 212k mm·r/min. Light-load floor: Pu = 20.8 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51415 M; the number is 8 % of the 251 kN dynamic rating. Minimum-load arithmetic: with dm ≈ 117.5 mm and factor A 1.9, Fam ≈ A·(n·dm/1000)² at the 1,300 r/min reference speed is about 44.3 kN for 51415 M; below that preload the balls skid and smear the tracks. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51415 M adds a small amount of mass and cage strength without changing the 75×160×65 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,800 r/min ceiling.", "applications": [ "winch drums and reducer housings", "vertical motor and pump thrust bearings", "heavy crane hooks and hoist blocks" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "When the housing seat cannot be machined square to the 75 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51400 bearing.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 251/610 kN and the available 160 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 251 kN track before first rotation.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51415 against two-way load lifts the loose washer off its raceway.", "Ordering discipline for 51415: the catalogue page quotes 51415 M and its 251/610 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51415-M?", "a": "51415 M measures 75 mm bore × 160 mm OD × 65 mm bearing height (2.953 × 6.299 × 2.559 in), mass about 6750 g. SKF 17000 ratings: C 251 kN, C0 610 kN, Pu 20.8 kN, reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical)." }, { "q": "What does the designation 51415 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 15 encode the bore as 75 mm (code 15 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can a single 51415 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." }, { "q": "What do the two published speeds mean for 51415-M?", "a": "The 1,300 r/min reference speed is the thermal balance under catalogue load; the 1,800 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." } ], "cross_ref": [ { "equiv_sku": "51415", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51415-M", "51415 M" ], "locale_variants": {} }, { "sku": "51116-SKF", "brand": "SKF", "manufacturer_designation": "51116", "series": "51100-series", "type": "thrust_ball", "d_mm": 80, "D_mm": 105, "B_mm": 19, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 44.9, "static_load_kN": 140, "fatigue_load_limit_kN": 5.1, "reference_speed_rpm": 3000, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 420, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51116 is an ISO 104 single-direction thrust ball bearing, 80 mm bore and 105 mm OD on a flat housing seat, standing 19 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 16: bore 80 mm (code 16 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 80×105×19 mm (3.15×4.134×0.748 in), 12.5 mm radial section, C 44.9 kN, C0 140 kN, Pu 5.1 kN. reference speed 3,000 r/min (thermal) and limiting speed 4,300 r/min (mechanical), catalogue mass 420 g. Static-first selection data: 140 kN C0 spread across the 19 mm stack gives 7.4 kN of static rating per height millimetre, and the 420 g mass/C0 ratio is about 3 g per static kN — crane-hook and screw positions are normally sized on these two figures. Speed band width for this size is 1,300 r/min between reference and limiting (1.43× ratio); lubrication, preload and heat removal decide where inside that band 51116 can actually run. Capacity density: 44.9 kN C from 0.420 kg of bearing steel gives about 106.9 kN per kilogram; static density is correspondingly 333.3 kN/kg at C0 140 kN. Mass and section check: 420 g inside the 80×105×19 mm outline leaves a 12.5 mm radial section, and the 140 kN static rating is 3.12× the dynamic rating — plan static safety and minimum preload against those figures. Stack/annulus proportions: the 19 mm axial stack over the 3,632 mm² washer annulus gives 5.23 mm of height per annular square millimetre ×10⁻³, and at 420 g the bearing holds about 333.3 kN of C0 per kilogram. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 19 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 44.9 kN C.", "applications": [ "turret and slewing-bearing adjustment screws", "heavy crane hooks and hoist blocks", "vertical motor and pump thrust bearings" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "false brinelling of the stationary tracks while the machine stands under vibration", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "When the housing seat cannot be machined square to the 80 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 44.9 kN track before first rotation.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51116 against two-way load lifts the loose washer off its raceway.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 44.9/140 kN and the available 105 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Ordering discipline for 51116: the catalogue page quotes 51116 and its 44.9/140 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51116-SKF?", "a": "The catalogue envelope is 80×105×19 mm, mass 420 g; ratings C 44.9 kN / C0 140 kN / Pu 5.1 kN, reference speed 3,000 r/min (thermal) and limiting speed 4,300 r/min (mechanical)." }, { "q": "What does the designation 51116 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 16: bore 80 mm (code 16 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can a single 51116 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." }, { "q": "What do the two published speeds mean for 51116-SKF?", "a": "The 3,000 r/min reference speed is the thermal balance under catalogue load; the 4,300 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." } ], "cross_ref": [ { "equiv_sku": "51116", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51116-SKF", "51116" ], "locale_variants": {} }, { "sku": "51216-SKF", "brand": "SKF", "manufacturer_designation": "51216", "series": "51200-series", "type": "thrust_ball", "d_mm": 80, "D_mm": 115, "B_mm": 28, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 76.1, "static_load_kN": 208, "fatigue_load_limit_kN": 7.65, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 910, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51200 series order number 51216 is a SKF single-direction thrust ball bearing for a 80 mm seat, built to ISO 104, with a flat housing seating surface, 80×115×28 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 16 decodes to 80 mm (code 16 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 80×115×28 mm (3.15×4.528×1.102 in), 17.5 mm radial section, C 76.1 kN, C0 208 kN, Pu 7.65 kN. reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical), catalogue mass 910 g. Rating split for documentation: dynamic 76.1 kN (L10 life), static 208 kN (safety factor s0), fatigue limit 7.65 kN (adjusted life) — three different uses of three different numbers for 51216, none interchangeable with another. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51216 covers about 5,360 mm², distributing C0 208 kN over a mean track circle of π·dm ≈ 306 mm. Sizing arithmetic on the 80 mm bore: 76.1 kN C over the 17.5 mm radial section gives 4.3 kN per section millimetre, and the 28 mm stack height is 1.60× that section — proportions typical of a 51200 thrust section. Load balance: C0 208 kN against C 76.1 kN gives a 2.73 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 7.65 kN enters the adjusted-life check. Static-first selection data: 208 kN C0 spread across the 28 mm stack gives 7.4 kN of static rating per height millimetre, and the 910 g mass/C0 ratio is about 4 g per static kN — crane-hook and screw positions are normally sized on these two figures. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 28 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 76.1 kN C.", "applications": [ "vertical motor and pump thrust bearings", "turret and slewing-bearing adjustment screws", "winch drums and reducer housings" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "pitting on one track sector from a perpetually eccentric thrust line", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 28 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 76.1/208 kN and the available 115 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.22; for 51216 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51216 as the single flat pressed steel execution; other order numbers of the 51216 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51216-SKF?", "a": "Boundary dimensions to ISO 104: bore 80 mm, OD 115 mm, height 28 mm; weight 910 g. Load figures from SKF 17000: dynamic 76.1 kN, static 208 kN, fatigue limit 7.65 kN; reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical)." }, { "q": "What does the designation 51216 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 16 decodes to 80 mm (code 16 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 80 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51216 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51216", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51216-SKF", "51216" ], "locale_variants": {} }, { "sku": "51316-SKF", "brand": "SKF", "manufacturer_designation": "51316", "series": "51300-series", "type": "thrust_ball", "d_mm": 80, "D_mm": 140, "B_mm": 44, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 159, "static_load_kN": 390, "fatigue_load_limit_kN": 13.7, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 2700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51300 series order number 51316 is a SKF single-direction thrust ball bearing for a 80 mm seat, built to ISO 104, with a flat housing seating surface, 80×140×44 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 16 decodes to 80 mm (code 16 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 80×140×44 mm (3.15×5.512×1.732 in), 30.0 mm radial section, C 159 kN, C0 390 kN, Pu 13.7 kN. reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical), catalogue mass 2700 g. Pitch-diameter arithmetic: dm = (80+140)/2 = 110.0 mm; at the 2,400 r/min limiting speed that corresponds to roughly 264k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Sizing arithmetic on the 80 mm bore: 159 kN C over the 30.0 mm radial section gives 5.3 kN per section millimetre, and the 44 mm stack height is 1.47× that section — proportions typical of a 51300 thrust section. At the printed limiting speed of 2,400 r/min the mean pitch diameter dm ≈ 110.0 mm implies a dn value around 264k mm·r/min; the 1,700 r/min reference speed is the thermal-planning value under catalogue load. Stack/annulus proportions: the 44 mm axial stack over the 10,367 mm² washer annulus gives 4.24 mm of height per annular square millimetre ×10⁻³, and at 2700 g the bearing holds about 144.4 kN of C0 per kilogram. Minimum-load arithmetic: with dm ≈ 110.0 mm and factor A 0.79, Fam ≈ A·(n·dm/1000)² at the 1,700 r/min reference speed is about 27.6 kN for 51316; below that preload the balls skid and smear the tracks. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 80 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 159/390 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "winch drums and reducer housings", "heavy crane hooks and hoist blocks", "vertical motor and pump thrust bearings" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "false brinelling of the stationary tracks while the machine stands under vibration", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.79; for 51316 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 159 kN track before first rotation.", "When the housing seat cannot be machined square to the 80 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51300 bearing.", "The 51316 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 80 mm shaft has to be carried by a radial bearing mounted alongside it.", "Ordering discipline for 51316: the catalogue page quotes 51316 and its 159/390 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51316-SKF?", "a": "Boundary dimensions to ISO 104: bore 80 mm, OD 140 mm, height 44 mm; weight 2700 g. Load figures from SKF 17000: dynamic 159 kN, static 390 kN, fatigue limit 13.7 kN; reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical)." }, { "q": "What does the designation 51316 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 16 decodes to 80 mm (code 16 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51316-SKF need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.79 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51316", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51316-SKF", "51316" ], "locale_variants": {} }, { "sku": "51416-M", "brand": "SKF", "manufacturer_designation": "51416 M", "series": "51400-series", "type": "thrust_ball", "d_mm": 80, "D_mm": 170, "B_mm": 68, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 302, "static_load_kN": 750, "fatigue_load_limit_kN": 25, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1700, "max_rpm": 1700, "weight_g": 7950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51416 M is SKF's 80 mm-bore single-direction thrust ball bearing in the 51400 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 80×170×68 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 16 encode the bore as 80 mm (code 16 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 80×170×68 mm (3.15×6.693×2.677 in), 45.0 mm radial section, C 302 kN, C0 750 kN, Pu 25 kN. reference speed 1,200 r/min (thermal) and limiting speed 1,700 r/min (mechanical), catalogue mass 7950 g. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 2.3 at the 1,700 r/min limiting speed raises the required axial preload to about 103.9 kN; the reference-speed value 51.7 kN is the thermal design point. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51416 M covers about 17,671 mm², distributing C0 750 kN over a mean track circle of π·dm ≈ 393 mm. Minimum-load arithmetic: with dm ≈ 125.0 mm and factor A 2.3, Fam ≈ A·(n·dm/1000)² at the 1,200 r/min reference speed is about 51.7 kN for 51416 M; below that preload the balls skid and smear the tracks. Sizing arithmetic on the 80 mm bore: 302 kN C over the 45.0 mm radial section gives 6.7 kN per section millimetre, and the 68 mm stack height is 1.51× that section — proportions typical of a 51400 thrust section. Imperial cross-check for procurement drawings: 3.15 in bore, 6.693 in OD, 2.677 in height, and the 7950 g catalogue mass converts to 7.950 kg (280.4 oz). Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 7950 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 80 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "vertical motor and pump thrust bearings", "heavy crane hooks and hoist blocks", "large screw jacks and press rams" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "The 51416 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 80 mm shaft has to be carried by a radial bearing mounted alongside it.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51416 against two-way load lifts the loose washer off its raceway.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 302 kN track before first rotation.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51416 M as the single flat brass execution; other order numbers of the 51416 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51416-M?", "a": "51416 M measures 80 mm bore × 170 mm OD × 68 mm bearing height (3.15 × 6.693 × 2.677 in), mass about 7950 g. SKF 17000 ratings: C 302 kN, C0 750 kN, Pu 25 kN, reference speed 1,200 r/min (thermal) and limiting speed 1,700 r/min (mechanical)." }, { "q": "What does the designation 51416 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 16 encode the bore as 80 mm (code 16 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number is a different, M-cage product) uses the standard stamped sheet-steel pressed cage." }, { "q": "Can 51416-M carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 80 mm shaft must go to a separate radial bearing; mixed loading through 51416 M edge-loads the balls and destroys the washers." } ], "cross_ref": [ { "equiv_sku": "51416", "equiv_brand": "NTN", "level": "partial", "note": "Same 80×170×68 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51416-M", "51416 M" ], "locale_variants": {} }, { "sku": "51117-SKF", "brand": "SKF", "manufacturer_designation": "51117", "series": "51100-series", "type": "thrust_ball", "d_mm": 85, "D_mm": 110, "B_mm": 19, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 44.9, "static_load_kN": 146, "fatigue_load_limit_kN": 5.4, "reference_speed_rpm": 3000, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51117 is a SKF single-direction thrust ball bearing for a 85 mm seat, built to ISO 104, with a flat housing seating surface, 85×110×19 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 17 decodes to 85 mm (code 17 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 85×110×19 mm (3.346×4.331×0.748 in), 12.5 mm radial section, C 44.9 kN, C0 146 kN, Pu 5.4 kN. reference speed 3,000 r/min (thermal) and limiting speed 4,300 r/min (mechanical), catalogue mass 440 g. Load balance: C0 146 kN against C 44.9 kN gives a 3.25 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 5.4 kN enters the adjusted-life check. Envelope economics: the 19 mm axial height over a 12.5 mm radial section yields 2.4 kN of dynamic capacity per height millimetre, and the bearing weighs 440 g for 44.9 kN C — about 10 g per rated kN. Sizing arithmetic on the 85 mm bore: 44.9 kN C over the 12.5 mm radial section gives 3.6 kN per section millimetre, and the 19 mm stack height is 1.52× that section — proportions typical of a 51100 thrust section. Speed band width for this size is 1,300 r/min between reference and limiting (1.43× ratio); lubrication, preload and heat removal decide where inside that band 51117 can actually run. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51117 covers about 3,829 mm², distributing C0 146 kN over a mean track circle of π·dm ≈ 306 mm. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 19 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 44.9 kN C.", "applications": [ "vertical motor and pump thrust bearings", "heavy crane hooks and hoist blocks", "large screw jacks and press rams" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51117 against two-way load lifts the loose washer off its raceway.", "When the housing seat cannot be machined square to the 85 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 19 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The 44.9/146 kN figures belong to 51117 specifically (the single flat pressed steel execution of 51117); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51117-SKF?", "a": "Boundary dimensions to ISO 104: bore 85 mm, OD 110 mm, height 19 mm; weight 440 g. Load figures from SKF 17000: dynamic 44.9 kN, static 146 kN, fatigue limit 5.4 kN; reference speed 3,000 r/min (thermal) and limiting speed 4,300 r/min (mechanical)." }, { "q": "What does the designation 51117 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 17 decodes to 85 mm (code 17 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51117-SKF?", "a": "The 3,000 r/min reference speed is the thermal balance under catalogue load; the 4,300 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51117-SKF need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.14 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51117", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51117-SKF", "51117" ], "locale_variants": {} }, { "sku": "51217-SKF", "brand": "SKF", "manufacturer_designation": "51217", "series": "51200-series", "type": "thrust_ball", "d_mm": 85, "D_mm": 125, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 97.5, "static_load_kN": 275, "fatigue_load_limit_kN": 9.8, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51217 is an ISO 104 single-direction thrust ball bearing, 85 mm bore and 125 mm OD on a flat housing seat, standing 31 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 17: bore 85 mm (code 17 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 85×125×31 mm (3.346×4.921×1.22 in), 20.0 mm radial section, C 97.5 kN, C0 275 kN, Pu 9.8 kN. reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical), catalogue mass 1200 g. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51217 covers about 6,597 mm², distributing C0 275 kN over a mean track circle of π·dm ≈ 330 mm. Load balance: C0 275 kN against C 97.5 kN gives a 2.82 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 9.8 kN enters the adjusted-life check. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.39 at the 3,000 r/min limiting speed raises the required axial preload to about 38.7 kN; the reference-speed value 20.8 kN is the thermal design point. Capacity density: 97.5 kN C from 1.200 kg of bearing steel gives about 81.3 kN per kilogram; static density is correspondingly 229.2 kN/kg at C0 275 kN. Track-circle loading: per millimetre of mean track circumference the 97.5 kN dynamic rating corresponds to roughly 0.30 kN/mm of π·dm track, a useful comparison against the other dimension series of the 85 mm bore. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 31 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 97.5 kN C.", "applications": [ "turret and slewing-bearing adjustment screws", "vertical motor and pump thrust bearings", "winch drums and reducer housings" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "cage damage from mounting force applied through the balls instead of the washer face", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "When the housing seat cannot be machined square to the 85 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 85 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 31 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Ordering discipline for 51217: the catalogue page quotes 51217 and its 97.5/275 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51217-SKF?", "a": "The catalogue envelope is 85×125×31 mm, mass 1200 g; ratings C 97.5 kN / C0 275 kN / Pu 9.8 kN, reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical)." }, { "q": "What does the designation 51217 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 17: bore 85 mm (code 17 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51217-SKF lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 3,000 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 85 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51217", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51217-SKF", "51217" ], "locale_variants": {} }, { "sku": "51317-SKF", "brand": "SKF", "manufacturer_designation": "51317", "series": "51300-series", "type": "thrust_ball", "d_mm": 85, "D_mm": 150, "B_mm": 49, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 174, "static_load_kN": 405, "fatigue_load_limit_kN": 14, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 3550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51317 is SKF's 85 mm-bore single-direction thrust ball bearing in the 51300 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 85×150×49 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 17 encode the bore as 85 mm (code 17 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 85×150×49 mm (3.346×5.906×1.929 in), 32.5 mm radial section, C 174 kN, C0 405 kN, Pu 14 kN. reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical), catalogue mass 3550 g. Rating split for documentation: dynamic 174 kN (L10 life), static 405 kN (safety factor s0), fatigue limit 14 kN (adjusted life) — three different uses of three different numbers for 51317, none interchangeable with another. Imperial cross-check for procurement drawings: 3.346 in bore, 5.906 in OD, 1.929 in height, and the 3550 g catalogue mass converts to 3.550 kg (125.2 oz). Speed band width for this size is 600 r/min between reference and limiting (1.38× ratio); lubrication, preload and heat removal decide where inside that band 51317 can actually run. Section proportions: the 32.5 mm radial section compares with 85 mm of bore (section/bore ≈ 0.38) and the 49 mm height is 1.51× that section — the proportions that identify the 51300 envelope at a glance. Envelope economics: the 49 mm axial height over a 32.5 mm radial section yields 3.6 kN of dynamic capacity per height millimetre, and the bearing weighs 3550 g for 174 kN C — about 20 g per rated kN. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 49 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 174 kN C.", "applications": [ "heavy crane hooks and hoist blocks", "vertical motor and pump thrust bearings", "winch drums and reducer housings" ], "failure_modes": [ "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "raceway indentation from driving the bearing home through the ball set rather than the washer face" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 49 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 85 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "The 51317 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 85 mm shaft has to be carried by a radial bearing mounted alongside it.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51317 as the single flat pressed steel execution; other order numbers of the 51317 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51317-SKF?", "a": "51317 measures 85 mm bore × 150 mm OD × 49 mm bearing height (3.346 × 5.906 × 1.929 in), mass about 3550 g. SKF 17000 ratings: C 174 kN, C0 405 kN, Pu 14 kN, reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical)." }, { "q": "What does the designation 51317 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 17 encode the bore as 85 mm (code 17 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." }, { "q": "Can 51317-SKF carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 85 mm shaft must go to a separate radial bearing; mixed loading through 51317 edge-loads the balls and destroys the washers." } ], "cross_ref": [ { "equiv_sku": "51317", "equiv_brand": "NTN", "level": "partial", "note": "Same 85×150×49 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51317-SKF", "51317" ], "locale_variants": {} }, { "sku": "51417-M", "brand": "SKF", "manufacturer_designation": "51417 M", "series": "51400-series", "type": "thrust_ball", "d_mm": 85, "D_mm": 180, "B_mm": 72, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 286, "static_load_kN": 750, "fatigue_load_limit_kN": 24, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1600, "max_rpm": 1600, "weight_g": 9450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51400 series order number 51417 M is a SKF single-direction thrust ball bearing for a 85 mm seat, built to ISO 104, with a flat housing seating surface, 85×180×72 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 17 decodes to 85 mm (code 17 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 85×180×72 mm (3.346×7.087×2.835 in), 47.5 mm radial section, C 286 kN, C0 750 kN, Pu 24 kN. reference speed 1,200 r/min (thermal) and limiting speed 1,600 r/min (mechanical), catalogue mass 9450 g. Speed planning separates the two ceilings mechanically: the pressed brass cage and balls tolerate 1,600 r/min while thermal balance under catalogue load sets the 1,200 r/min reference; at dm ≈ 132.5 mm the corresponding dn is approximately 212k mm·r/min. Light-load floor: Pu = 24 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51417 M; the number is 8 % of the 286 kN dynamic rating. Capacity density: 286 kN C from 9.450 kg of bearing steel gives about 30.3 kN per kilogram; static density is correspondingly 79.4 kN/kg at C0 750 kN. Minimum-load arithmetic: with dm ≈ 132.5 mm and factor A 2.9, Fam ≈ A·(n·dm/1000)² at the 1,200 r/min reference speed is about 73.3 kN for 51417 M; below that preload the balls skid and smear the tracks. Sizing arithmetic on the 85 mm bore: 286 kN C over the 47.5 mm radial section gives 6.0 kN per section millimetre, and the 72 mm stack height is 1.52× that section — proportions typical of a 51400 thrust section. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 9450 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 85 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "heavy crane hooks and hoist blocks", "large screw jacks and press rams", "turret and slewing-bearing adjustment screws" ], "failure_modes": [ "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "track rust staining from condensate during long idle periods in humid plant air", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 286/750 kN and the available 180 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The 51417 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 85 mm shaft has to be carried by a radial bearing mounted alongside it.", "When the housing seat cannot be machined square to the 85 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51400 bearing.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Ordering discipline for 51417: the catalogue page quotes 51417 M and its 286/750 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51417-M?", "a": "Boundary dimensions to ISO 104: bore 85 mm, OD 180 mm, height 72 mm; weight 9450 g. Load figures from SKF 17000: dynamic 286 kN, static 750 kN, fatigue limit 24 kN; reference speed 1,200 r/min (thermal) and limiting speed 1,600 r/min (mechanical)." }, { "q": "What does the designation 51417 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 17 decodes to 85 mm (code 17 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51417-M lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 1,600 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 85 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51417", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51417-M", "51417 M" ], "locale_variants": {} }, { "sku": "51118-SKF", "brand": "SKF", "manufacturer_designation": "51118", "series": "51100-series", "type": "thrust_ball", "d_mm": 90, "D_mm": 120, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 59.2, "static_load_kN": 208, "fatigue_load_limit_kN": 7.5, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 670, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51118 is an ISO 104 single-direction thrust ball bearing, 90 mm bore and 120 mm OD on a flat housing seat, standing 22 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 18: bore 90 mm (code 18 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 90×120×22 mm (3.543×4.724×0.866 in), 15.0 mm radial section, C 59.2 kN, C0 208 kN, Pu 7.5 kN. reference speed 2,600 r/min (thermal) and limiting speed 3,800 r/min (mechanical), catalogue mass 670 g. Mass and section check: 670 g inside the 90×120×22 mm outline leaves a 15.0 mm radial section, and the 208 kN static rating is 3.51× the dynamic rating — plan static safety and minimum preload against those figures. Light-load floor: Pu = 7.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51118; the number is 13 % of the 59.2 kN dynamic rating. Imperial cross-check for procurement drawings: 3.543 in bore, 4.724 in OD, 0.866 in height, and the 670 g catalogue mass converts to 0.670 kg (23.6 oz). Load balance: C0 208 kN against C 59.2 kN gives a 3.51 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 7.5 kN enters the adjusted-life check. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.22 at the 3,800 r/min limiting speed raises the required axial preload to about 35.0 kN; the reference-speed value 16.4 kN is the thermal design point. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 90 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 59.2/208 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "large screw jacks and press rams", "vertical motor and pump thrust bearings", "turret and slewing-bearing adjustment screws" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "cage damage from mounting force applied through the balls instead of the washer face", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "When the housing seat cannot be machined square to the 90 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 22 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51118 against two-way load lifts the loose washer off its raceway.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Ordering discipline for 51118: the catalogue page quotes 51118 and its 59.2/208 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51118-SKF?", "a": "The catalogue envelope is 90×120×22 mm, mass 670 g; ratings C 59.2 kN / C0 208 kN / Pu 7.5 kN, reference speed 2,600 r/min (thermal) and limiting speed 3,800 r/min (mechanical)." }, { "q": "What does the designation 51118 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 18: bore 90 mm (code 18 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51118-SKF need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.22 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51118", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51118-SKF", "51118" ], "locale_variants": {} }, { "sku": "51218-SKF", "brand": "SKF", "manufacturer_designation": "51218", "series": "51200-series", "type": "thrust_ball", "d_mm": 90, "D_mm": 135, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 112, "static_load_kN": 290, "fatigue_load_limit_kN": 10.4, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 1700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51218 is SKF's 90 mm-bore single-direction thrust ball bearing in the 51200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 90×135×35 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 18 encode the bore as 90 mm (code 18 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 90×135×35 mm (3.543×5.315×1.378 in), 22.5 mm radial section, C 112 kN, C0 290 kN, Pu 10.4 kN. reference speed 2,000 r/min (thermal) and limiting speed 2,800 r/min (mechanical), catalogue mass 1700 g. Sizing arithmetic on the 90 mm bore: 112 kN C over the 22.5 mm radial section gives 5.0 kN per section millimetre, and the 35 mm stack height is 1.56× that section — proportions typical of a 51200 thrust section. Envelope economics: the 35 mm axial height over a 22.5 mm radial section yields 3.2 kN of dynamic capacity per height millimetre, and the bearing weighs 1700 g for 112 kN C — about 15 g per rated kN. Pitch-diameter arithmetic: dm = (90+135)/2 = 112.5 mm; at the 2,800 r/min limiting speed that corresponds to roughly 315k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Mass and section check: 1700 g inside the 90×135×35 mm outline leaves a 22.5 mm radial section, and the 290 kN static rating is 2.59× the dynamic rating — plan static safety and minimum preload against those figures. Section proportions: the 22.5 mm radial section compares with 90 mm of bore (section/bore ≈ 0.25) and the 35 mm height is 1.56× that section — the proportions that identify the 51200 envelope at a glance. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 35 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 112 kN C.", "applications": [ "winch drums and reducer housings", "large screw jacks and press rams", "heavy crane hooks and hoist blocks" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "false brinelling of the stationary tracks while the machine stands under vibration" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 35 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 90 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 112 kN track before first rotation.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51218 as the single flat pressed steel execution; other order numbers of the 51218 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51218-SKF?", "a": "51218 measures 90 mm bore × 135 mm OD × 35 mm bearing height (3.543 × 5.315 × 1.378 in), mass about 1700 g. SKF 17000 ratings: C 112 kN, C0 290 kN, Pu 10.4 kN, reference speed 2,000 r/min (thermal) and limiting speed 2,800 r/min (mechanical)." }, { "q": "What does the designation 51218 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 18 encode the bore as 90 mm (code 18 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." }, { "q": "How is 51218-SKF lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 2,800 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "51218", "equiv_brand": "NTN", "level": "partial", "note": "Same 90×135×35 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51218-SKF", "51218" ], "locale_variants": {} }, { "sku": "51318-SKF", "brand": "SKF", "manufacturer_designation": "51318", "series": "51300-series", "type": "thrust_ball", "d_mm": 90, "D_mm": 155, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 182, "static_load_kN": 440, "fatigue_load_limit_kN": 14.6, "reference_speed_rpm": 1500, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 3800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51300 series order number 51318 is a SKF single-direction thrust ball bearing for a 90 mm seat, built to ISO 104, with a flat housing seating surface, 90×155×50 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 18 decodes to 90 mm (code 18 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 90×155×50 mm (3.543×6.102×1.969 in), 32.5 mm radial section, C 182 kN, C0 440 kN, Pu 14.6 kN. reference speed 1,500 r/min (thermal) and limiting speed 2,200 r/min (mechanical), catalogue mass 3800 g. Pitch-diameter arithmetic: dm = (90+155)/2 = 122.5 mm; at the 2,200 r/min limiting speed that corresponds to roughly 270k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Rating split for documentation: dynamic 182 kN (L10 life), static 440 kN (safety factor s0), fatigue limit 14.6 kN (adjusted life) — three different uses of three different numbers for 51318, none interchangeable with another. Section proportions: the 32.5 mm radial section compares with 90 mm of bore (section/bore ≈ 0.36) and the 50 mm height is 1.54× that section — the proportions that identify the 51300 envelope at a glance. Minimum-load arithmetic: with dm ≈ 122.5 mm and factor A 1.3, Fam ≈ A·(n·dm/1000)² at the 1,500 r/min reference speed is about 43.9 kN for 51318; below that preload the balls skid and smear the tracks. Light-load floor: Pu = 14.6 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51318; the number is 8 % of the 182 kN dynamic rating. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 90 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 182/440 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "vertical motor and pump thrust bearings", "winch drums and reducer housings", "heavy crane hooks and hoist blocks" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "When the housing seat cannot be machined square to the 90 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51300 bearing.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 1.3; for 51318 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The 51318 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 90 mm shaft has to be carried by a radial bearing mounted alongside it.", "The 182/440 kN figures belong to 51318 specifically (the single flat pressed steel execution of 51318); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51318-SKF?", "a": "Boundary dimensions to ISO 104: bore 90 mm, OD 155 mm, height 50 mm; weight 3800 g. Load figures from SKF 17000: dynamic 182 kN, static 440 kN, fatigue limit 14.6 kN; reference speed 1,500 r/min (thermal) and limiting speed 2,200 r/min (mechanical)." }, { "q": "What does the designation 51318 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 18 decodes to 90 mm (code 18 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can a single 51318 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." }, { "q": "What do the two published speeds mean for 51318-SKF?", "a": "The 1,500 r/min reference speed is the thermal balance under catalogue load; the 2,200 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." } ], "cross_ref": [ { "equiv_sku": "51318", "equiv_brand": "NTN", "level": "partial", "note": "Same 90×155×50 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51318-SKF", "51318" ], "locale_variants": {} }, { "sku": "51418-M", "brand": "SKF", "manufacturer_designation": "51418 M", "series": "51400-series", "type": "thrust_ball", "d_mm": 90, "D_mm": 190, "B_mm": 77, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 307, "static_load_kN": 815, "fatigue_load_limit_kN": 25.5, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1500, "max_rpm": 1500, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51400 series order number 51418 M is a SKF single-direction thrust ball bearing for a 90 mm seat, built to ISO 104, with a flat housing seating surface, 90×190×77 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 18 decodes to 90 mm (code 18 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 90×190×77 mm (3.543×7.48×3.031 in), 50.0 mm radial section, C 307 kN, C0 815 kN, Pu 25.5 kN. reference speed 1,100 r/min (thermal) and limiting speed 1,500 r/min (mechanical), catalogue mass 11000 g. Bore-to-OD planning: OD 190 over bore 90 is a 2.11× step for this size, and the 77 mm height gives a bore/height ratio of 1.17; use these ratios when the housing recess around the 90 mm shaft is the first constraint. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51418 M covers about 21,991 mm², distributing C0 815 kN over a mean track circle of π·dm ≈ 440 mm. Speed band width for this size is 400 r/min between reference and limiting (1.36× ratio); lubrication, preload and heat removal decide where inside that band 51418 M can actually run. Sizing arithmetic on the 90 mm bore: 307 kN C over the 50.0 mm radial section gives 6.1 kN per section millimetre, and the 77 mm stack height is 1.54× that section — proportions typical of a 51400 thrust section. Imperial cross-check for procurement drawings: 3.543 in bore, 7.48 in OD, 3.031 in height, and the 11000 g catalogue mass converts to 11.000 kg (388.0 oz). Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51418 M adds a small amount of mass and cage strength without changing the 90×190×77 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,500 r/min ceiling.", "applications": [ "vertical motor and pump thrust bearings", "winch drums and reducer housings", "turret and slewing-bearing adjustment screws" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "false brinelling of the stationary tracks while the machine stands under vibration" ], "pitfalls": [ "When the housing seat cannot be machined square to the 90 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51400 bearing.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51418 against two-way load lifts the loose washer off its raceway.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 307/815 kN and the available 190 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 90 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Ordering discipline for 51418: the catalogue page quotes 51418 M and its 307/815 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51418-M?", "a": "Boundary dimensions to ISO 104: bore 90 mm, OD 190 mm, height 77 mm; weight 11000 g. Load figures from SKF 17000: dynamic 307 kN, static 815 kN, fatigue limit 25.5 kN; reference speed 1,100 r/min (thermal) and limiting speed 1,500 r/min (mechanical)." }, { "q": "What does the designation 51418 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 18 decodes to 90 mm (code 18 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51418-M?", "a": "The 1,100 r/min reference speed is the thermal balance under catalogue load; the 1,500 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51418-M need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 3.5 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51418", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51418-M", "51418 M" ], "locale_variants": {} }, { "sku": "51120-SKF", "brand": "SKF", "manufacturer_designation": "51120", "series": "51100-series", "type": "thrust_ball", "d_mm": 100, "D_mm": 135, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 80.6, "static_load_kN": 265, "fatigue_load_limit_kN": 9.15, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 970, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51120 is SKF's 100 mm-bore single-direction thrust ball bearing in the 51100 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 100×135×25 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 20 encode the bore as 100 mm (code 20 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 100×135×25 mm (3.937×5.315×0.984 in), 17.5 mm radial section, C 80.6 kN, C0 265 kN, Pu 9.15 kN. reference speed 2,400 r/min (thermal) and limiting speed 3,200 r/min (mechanical), catalogue mass 970 g. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.44 at the 3,200 r/min limiting speed raises the required axial preload to about 62.2 kN; the reference-speed value 35.0 kN is the thermal design point. Bore-to-OD planning: OD 135 over bore 100 is a 1.35× step for this size, and the 25 mm height gives a bore/height ratio of 4.00; use these ratios when the housing recess around the 100 mm shaft is the first constraint. Rating split for documentation: dynamic 80.6 kN (L10 life), static 265 kN (safety factor s0), fatigue limit 9.15 kN (adjusted life) — three different uses of three different numbers for 51120, none interchangeable with another. Capacity density: 80.6 kN C from 0.970 kg of bearing steel gives about 83.1 kN per kilogram; static density is correspondingly 273.2 kN/kg at C0 265 kN. Track-circle loading: per millimetre of mean track circumference the 80.6 kN dynamic rating corresponds to roughly 0.22 kN/mm of π·dm track, a useful comparison against the other dimension series of the 100 mm bore. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 25 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 80.6 kN C.", "applications": [ "winch drums and reducer housings", "heavy crane hooks and hoist blocks", "turret and slewing-bearing adjustment screws" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "track rust staining from condensate during long idle periods in humid plant air" ], "pitfalls": [ "The 51120 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 100 mm shaft has to be carried by a radial bearing mounted alongside it.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51120 against two-way load lifts the loose washer off its raceway.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 100 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.44; for 51120 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51120 as the single flat pressed steel execution; other order numbers of the 51120 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51120-SKF?", "a": "51120 measures 100 mm bore × 135 mm OD × 25 mm bearing height (3.937 × 5.315 × 0.984 in), mass about 970 g. SKF 17000 ratings: C 80.6 kN, C0 265 kN, Pu 9.15 kN, reference speed 2,400 r/min (thermal) and limiting speed 3,200 r/min (mechanical)." }, { "q": "What does the designation 51120 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 20 encode the bore as 100 mm (code 20 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 100 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51120 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51120", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51120-SKF", "51120" ], "locale_variants": {} }, { "sku": "51220-SKF", "brand": "SKF", "manufacturer_designation": "51220", "series": "51200-series", "type": "thrust_ball", "d_mm": 100, "D_mm": 150, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 119, "static_load_kN": 325, "fatigue_load_limit_kN": 10.8, "reference_speed_rpm": 1800, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 2200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51220 is an ISO 104 single-direction thrust ball bearing, 100 mm bore and 150 mm OD on a flat housing seat, standing 38 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 20: bore 100 mm (code 20 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 100×150×38 mm (3.937×5.906×1.496 in), 25.0 mm radial section, C 119 kN, C0 325 kN, Pu 10.8 kN. reference speed 1,800 r/min (thermal) and limiting speed 2,400 r/min (mechanical), catalogue mass 2200 g. Bore-to-OD planning: OD 150 over bore 100 is a 1.50× step for this size, and the 38 mm height gives a bore/height ratio of 2.63; use these ratios when the housing recess around the 100 mm shaft is the first constraint. Sizing arithmetic on the 100 mm bore: 119 kN C over the 25.0 mm radial section gives 4.8 kN per section millimetre, and the 38 mm stack height is 1.52× that section — proportions typical of a 51200 thrust section. Load balance: C0 325 kN against C 119 kN gives a 2.73 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 10.8 kN enters the adjusted-life check. Stack/annulus proportions: the 38 mm axial stack over the 9,817 mm² washer annulus gives 3.87 mm of height per annular square millimetre ×10⁻³, and at 2200 g the bearing holds about 147.7 kN of C0 per kilogram. Mass and section check: 2200 g inside the 100×150×38 mm outline leaves a 25.0 mm radial section, and the 325 kN static rating is 2.73× the dynamic rating — plan static safety and minimum preload against those figures. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 38 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 119 kN C.", "applications": [ "turret and slewing-bearing adjustment screws", "winch drums and reducer housings", "vertical motor and pump thrust bearings" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "washer face scoring from swarf trapped between the loose housing washer and its register", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51220 against two-way load lifts the loose washer off its raceway.", "When the housing seat cannot be machined square to the 100 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 38 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 100 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51220 as the single flat pressed steel execution; other order numbers of the 51220 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51220-SKF?", "a": "The catalogue envelope is 100×150×38 mm, mass 2200 g; ratings C 119 kN / C0 325 kN / Pu 10.8 kN, reference speed 1,800 r/min (thermal) and limiting speed 2,400 r/min (mechanical)." }, { "q": "What does the designation 51220 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 20: bore 100 mm (code 20 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can 51220-SKF carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 100 mm shaft must go to a separate radial bearing; mixed loading through 51220 edge-loads the balls and destroys the washers." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." } ], "cross_ref": [ { "equiv_sku": "51220", "equiv_brand": "NTN", "level": "partial", "note": "Same 100×150×38 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51220-SKF", "51220" ], "locale_variants": {} }, { "sku": "51320-SKF", "brand": "SKF", "manufacturer_designation": "51320", "series": "51300-series", "type": "thrust_ball", "d_mm": 100, "D_mm": 170, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 225, "static_load_kN": 570, "fatigue_load_limit_kN": 18.3, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1900, "max_rpm": 1900, "weight_g": 4950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51300 series order number 51320 is a SKF single-direction thrust ball bearing for a 100 mm seat, built to ISO 104, with a flat housing seating surface, 100×170×55 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 20 decodes to 100 mm (code 20 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 100×170×55 mm (3.937×6.693×2.165 in), 35.0 mm radial section, C 225 kN, C0 570 kN, Pu 18.3 kN. reference speed 1,400 r/min (thermal) and limiting speed 1,900 r/min (mechanical), catalogue mass 4950 g. Imperial cross-check for procurement drawings: 3.937 in bore, 6.693 in OD, 2.165 in height, and the 4950 g catalogue mass converts to 4.950 kg (174.6 oz). Section proportions: the 35.0 mm radial section compares with 100 mm of bore (section/bore ≈ 0.35) and the 55 mm height is 1.57× that section — the proportions that identify the 51300 envelope at a glance. Rating split for documentation: dynamic 225 kN (L10 life), static 570 kN (safety factor s0), fatigue limit 18.3 kN (adjusted life) — three different uses of three different numbers for 51320, none interchangeable with another. Bore-to-OD planning: OD 170 over bore 100 is a 1.70× step for this size, and the 55 mm height gives a bore/height ratio of 1.82; use these ratios when the housing recess around the 100 mm shaft is the first constraint. Stack/annulus proportions: the 55 mm axial stack over the 14,844 mm² washer annulus gives 3.71 mm of height per annular square millimetre ×10⁻³, and at 4950 g the bearing holds about 115.2 kN of C0 per kilogram. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 100 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 225/570 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "turret and slewing-bearing adjustment screws", "vertical motor and pump thrust bearings", "heavy crane hooks and hoist blocks" ], "failure_modes": [ "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 1.9; for 51320 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "When the housing seat cannot be machined square to the 100 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51300 bearing.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 225/570 kN and the available 170 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Ordering discipline for 51320: the catalogue page quotes 51320 and its 225/570 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51320-SKF?", "a": "Boundary dimensions to ISO 104: bore 100 mm, OD 170 mm, height 55 mm; weight 4950 g. Load figures from SKF 17000: dynamic 225 kN, static 570 kN, fatigue limit 18.3 kN; reference speed 1,400 r/min (thermal) and limiting speed 1,900 r/min (mechanical)." }, { "q": "What does the designation 51320 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 20 decodes to 100 mm (code 20 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51320-SKF?", "a": "The 1,400 r/min reference speed is the thermal balance under catalogue load; the 1,900 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51320-SKF need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 1.9 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51320", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51320-SKF", "51320" ], "locale_variants": {} }, { "sku": "51420-M", "brand": "SKF", "manufacturer_designation": "51420 M", "series": "51400-series", "type": "thrust_ball", "d_mm": 100, "D_mm": 210, "B_mm": 85, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 371, "static_load_kN": 1060, "fatigue_load_limit_kN": 31.5, "reference_speed_rpm": 950, "limiting_speed_rpm": 1400, "max_rpm": 1400, "weight_g": 15000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51400 series order number 51420 M is a SKF single-direction thrust ball bearing for a 100 mm seat, built to ISO 104, with a flat housing seating surface, 100×210×85 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 20 decodes to 100 mm (code 20 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 100×210×85 mm (3.937×8.268×3.346 in), 55.0 mm radial section, C 371 kN, C0 1060 kN, Pu 31.5 kN. reference speed 950 r/min (thermal) and limiting speed 1,400 r/min (mechanical), catalogue mass 15000 g. Selection figures for 51420 M: the C0/C ratio is 2.86, Pu 31.5 kN is about 8 % of C, and the catalogue mass works out to roughly 150 g per millimetre of bore; the printed minimum-load factor is A 5.8. Capacity density: 371 kN C from 15.000 kg of bearing steel gives about 24.7 kN per kilogram; static density is correspondingly 70.7 kN/kg at C0 1060 kN. Minimum-load arithmetic: with dm ≈ 155.0 mm and factor A 5.8, Fam ≈ A·(n·dm/1000)² at the 950 r/min reference speed is about 125.8 kN for 51420 M; below that preload the balls skid and smear the tracks. Sizing arithmetic on the 100 mm bore: 371 kN C over the 55.0 mm radial section gives 6.7 kN per section millimetre, and the 85 mm stack height is 1.55× that section — proportions typical of a 51400 thrust section. Stack/annulus proportions: the 85 mm axial stack over the 26,782 mm² washer annulus gives 3.17 mm of height per annular square millimetre ×10⁻³, and at 15000 g the bearing holds about 70.7 kN of C0 per kilogram. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 15000 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 100 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "large screw jacks and press rams", "vertical motor and pump thrust bearings", "turret and slewing-bearing adjustment screws" ], "failure_modes": [ "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "cage damage from mounting force applied through the balls instead of the washer face", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "When the housing seat cannot be machined square to the 100 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51400 bearing.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 85 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 5.8; for 51420 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Ordering discipline for 51420: the catalogue page quotes 51420 M and its 371/1060 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51420-M?", "a": "Boundary dimensions to ISO 104: bore 100 mm, OD 210 mm, height 85 mm; weight 15000 g. Load figures from SKF 17000: dynamic 371 kN, static 1060 kN, fatigue limit 31.5 kN; reference speed 950 r/min (thermal) and limiting speed 1,400 r/min (mechanical)." }, { "q": "What does the designation 51420 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 20 decodes to 100 mm (code 20 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can a single 51420 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." }, { "q": "What do the two published speeds mean for 51420-M?", "a": "The 950 r/min reference speed is the thermal balance under catalogue load; the 1,400 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." } ], "cross_ref": [ { "equiv_sku": "51420", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51420-M", "51420 M" ], "locale_variants": {} }, { "sku": "51122", "brand": "SKF", "manufacturer_designation": "51122", "series": "51100-series", "type": "thrust_ball", "d_mm": 110, "D_mm": 145, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 83.2, "static_load_kN": 285, "fatigue_load_limit_kN": 9.5, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 1050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51122 is a SKF single-direction thrust ball bearing for a 110 mm seat, built to ISO 104, with a flat housing seating surface, 110×145×25 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 22 decodes to 110 mm (code 22 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 110×145×25 mm (4.331×5.709×0.984 in), 17.5 mm radial section, C 83.2 kN, C0 285 kN, Pu 9.5 kN. reference speed 2,200 r/min (thermal) and limiting speed 3,200 r/min (mechanical), catalogue mass 1050 g. Selection figures for 51122: the C0/C ratio is 3.43, Pu 9.5 kN is about 11 % of C, and the catalogue mass works out to roughly 10 g per millimetre of bore; the printed minimum-load factor is A 0.52. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.52 at the 3,200 r/min limiting speed raises the required axial preload to about 86.6 kN; the reference-speed value 40.9 kN is the thermal design point. Stack/annulus proportions: the 25 mm axial stack over the 7,010 mm² washer annulus gives 3.57 mm of height per annular square millimetre ×10⁻³, and at 1050 g the bearing holds about 271.4 kN of C0 per kilogram. Sizing arithmetic on the 110 mm bore: 83.2 kN C over the 17.5 mm radial section gives 4.8 kN per section millimetre, and the 25 mm stack height is 1.43× that section — proportions typical of a 51100 thrust section. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 3,200 r/min while thermal balance under catalogue load sets the 2,200 r/min reference; at dm ≈ 127.5 mm the corresponding dn is approximately 408k mm·r/min. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 25 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 83.2 kN C.", "applications": [ "turret and slewing-bearing adjustment screws", "vertical motor and pump thrust bearings", "winch drums and reducer housings" ], "failure_modes": [ "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "cage damage from mounting force applied through the balls instead of the washer face", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51122 against two-way load lifts the loose washer off its raceway.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 83.2 kN track before first rotation.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 83.2/285 kN and the available 145 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The 51122 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 110 mm shaft has to be carried by a radial bearing mounted alongside it.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51122 as the single flat pressed steel execution; other order numbers of the 51122 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51122?", "a": "Boundary dimensions to ISO 104: bore 110 mm, OD 145 mm, height 25 mm; weight 1050 g. Load figures from SKF 17000: dynamic 83.2 kN, static 285 kN, fatigue limit 9.5 kN; reference speed 2,200 r/min (thermal) and limiting speed 3,200 r/min (mechanical)." }, { "q": "What does the designation 51122 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 22 decodes to 110 mm (code 22 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51122 lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 3,200 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 110 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51122-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "51122", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51122" ], "locale_variants": {} }, { "sku": "51222", "brand": "SKF", "manufacturer_designation": "51222", "series": "51200-series", "type": "thrust_ball", "d_mm": 110, "D_mm": 160, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 125, "static_load_kN": 365, "fatigue_load_limit_kN": 11.6, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 2400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51222 is SKF's 110 mm-bore single-direction thrust ball bearing in the 51200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 110×160×38 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 22 encode the bore as 110 mm (code 22 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 110×160×38 mm (4.331×6.299×1.496 in), 25.0 mm radial section, C 125 kN, C0 365 kN, Pu 11.6 kN. reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical), catalogue mass 2400 g. Rating split for documentation: dynamic 125 kN (L10 life), static 365 kN (safety factor s0), fatigue limit 11.6 kN (adjusted life) — three different uses of three different numbers for 51222, none interchangeable with another. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 2,400 r/min while thermal balance under catalogue load sets the 1,700 r/min reference; at dm ≈ 135.0 mm the corresponding dn is approximately 324k mm·r/min. Capacity density: 125 kN C from 2.400 kg of bearing steel gives about 52.1 kN per kilogram; static density is correspondingly 152.1 kN/kg at C0 365 kN. Sizing arithmetic on the 110 mm bore: 125 kN C over the 25.0 mm radial section gives 5.0 kN per section millimetre, and the 38 mm stack height is 1.52× that section — proportions typical of a 51200 thrust section. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51222 covers about 10,603 mm², distributing C0 365 kN over a mean track circle of π·dm ≈ 424 mm. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 38 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 125 kN C.", "applications": [ "turret and slewing-bearing adjustment screws", "vertical motor and pump thrust bearings", "winch drums and reducer housings" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "raceway indentation from driving the bearing home through the ball set rather than the washer face" ], "pitfalls": [ "When the housing seat cannot be machined square to the 110 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.79; for 51222 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 125 kN track before first rotation.", "The 51222 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 110 mm shaft has to be carried by a radial bearing mounted alongside it.", "Ordering discipline for 51222: the catalogue page quotes 51222 and its 125/365 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51222?", "a": "51222 measures 110 mm bore × 160 mm OD × 38 mm bearing height (4.331 × 6.299 × 1.496 in), mass about 2400 g. SKF 17000 ratings: C 125 kN, C0 365 kN, Pu 11.6 kN, reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical)." }, { "q": "What does the designation 51222 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 22 encode the bore as 110 mm (code 22 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51222?", "a": "The 1,700 r/min reference speed is the thermal balance under catalogue load; the 2,400 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51222 need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.79 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51222-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 110×160×38 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51222", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51222" ], "locale_variants": {} }, { "sku": "51322-M", "brand": "SKF", "manufacturer_designation": "51322 M", "series": "51300-series", "type": "thrust_ball", "d_mm": 110, "D_mm": 190, "B_mm": 63, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 281, "static_load_kN": 815, "fatigue_load_limit_kN": 24.5, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1700, "max_rpm": 1700, "weight_g": 7850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51322 M is SKF's 110 mm-bore single-direction thrust ball bearing in the 51300 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 110×190×63 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 22 encode the bore as 110 mm (code 22 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 110×190×63 mm (4.331×7.48×2.48 in), 40.0 mm radial section, C 281 kN, C0 815 kN, Pu 24.5 kN. reference speed 1,200 r/min (thermal) and limiting speed 1,700 r/min (mechanical), catalogue mass 7850 g. Pitch-diameter arithmetic: dm = (110+190)/2 = 150.0 mm; at the 1,700 r/min limiting speed that corresponds to roughly 255k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51322 M covers about 18,850 mm², distributing C0 815 kN over a mean track circle of π·dm ≈ 471 mm. Sizing arithmetic on the 110 mm bore: 281 kN C over the 40.0 mm radial section gives 7.0 kN per section millimetre, and the 63 mm stack height is 1.57× that section — proportions typical of a 51300 thrust section. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 3.2 at the 1,700 r/min limiting speed raises the required axial preload to about 208.1 kN; the reference-speed value 103.7 kN is the thermal design point. Section proportions: the 40.0 mm radial section compares with 110 mm of bore (section/bore ≈ 0.36) and the 63 mm height is 1.57× that section — the proportions that identify the 51300 envelope at a glance. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 7850 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 110 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "heavy crane hooks and hoist blocks", "winch drums and reducer housings", "large screw jacks and press rams" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "false brinelling of the stationary tracks while the machine stands under vibration" ], "pitfalls": [ "The 51322 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 110 mm shaft has to be carried by a radial bearing mounted alongside it.", "When the housing seat cannot be machined square to the 110 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51300 bearing.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 110 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 281 kN track before first rotation.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51322 M as the single flat brass execution; other order numbers of the 51322 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51322-M?", "a": "51322 M measures 110 mm bore × 190 mm OD × 63 mm bearing height (4.331 × 7.48 × 2.48 in), mass about 7850 g. SKF 17000 ratings: C 281 kN, C0 815 kN, Pu 24.5 kN, reference speed 1,200 r/min (thermal) and limiting speed 1,700 r/min (mechanical)." }, { "q": "What does the designation 51322 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 22 encode the bore as 110 mm (code 22 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." }, { "q": "How is 51322-M lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 1,700 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "51322", "equiv_brand": "NTN", "level": "partial", "note": "Same 110×190×63 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51322", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51322-M", "51322 M" ], "locale_variants": {} }, { "sku": "51422-M", "brand": "SKF", "manufacturer_designation": "51422 M", "series": "51400-series", "type": "thrust_ball", "d_mm": 110, "D_mm": 230, "B_mm": 95, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 410, "static_load_kN": 1220, "fatigue_load_limit_kN": 34.5, "reference_speed_rpm": 900, "limiting_speed_rpm": 1300, "max_rpm": 1300, "weight_g": 20000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51400 series order number 51422 M is a SKF single-direction thrust ball bearing for a 110 mm seat, built to ISO 104, with a flat housing seating surface, 110×230×95 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 22 decodes to 110 mm (code 22 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 110×230×95 mm (4.331×9.055×3.74 in), 60.0 mm radial section, C 410 kN, C0 1220 kN, Pu 34.5 kN. reference speed 900 r/min (thermal) and limiting speed 1,300 r/min (mechanical), catalogue mass 20000 g. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 7.7 at the 1,300 r/min limiting speed raises the required axial preload to about 376.1 kN; the reference-speed value 180.2 kN is the thermal design point. Rating split for documentation: dynamic 410 kN (L10 life), static 1220 kN (safety factor s0), fatigue limit 34.5 kN (adjusted life) — three different uses of three different numbers for 51422 M, none interchangeable with another. Selection figures for 51422 M: the C0/C ratio is 2.98, Pu 34.5 kN is about 8 % of C, and the catalogue mass works out to roughly 182 g per millimetre of bore; the printed minimum-load factor is A 7.7. Light-load floor: Pu = 34.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51422 M; the number is 8 % of the 410 kN dynamic rating. Static-first selection data: 1220 kN C0 spread across the 95 mm stack gives 12.8 kN of static rating per height millimetre, and the 20000 g mass/C0 ratio is about 16 g per static kN — crane-hook and screw positions are normally sized on these two figures. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51422 M adds a small amount of mass and cage strength without changing the 110×230×95 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,300 r/min ceiling.", "applications": [ "winch drums and reducer housings", "heavy crane hooks and hoist blocks", "vertical motor and pump thrust bearings" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "false brinelling of the stationary tracks while the machine stands under vibration", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 7.7; for 51422 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51422 against two-way load lifts the loose washer off its raceway.", "When the housing seat cannot be machined square to the 110 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51400 bearing.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Ordering discipline for 51422: the catalogue page quotes 51422 M and its 410/1220 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51422-M?", "a": "Boundary dimensions to ISO 104: bore 110 mm, OD 230 mm, height 95 mm; weight 20000 g. Load figures from SKF 17000: dynamic 410 kN, static 1220 kN, fatigue limit 34.5 kN; reference speed 900 r/min (thermal) and limiting speed 1,300 r/min (mechanical)." }, { "q": "What does the designation 51422 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 22 decodes to 110 mm (code 22 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51422-M lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 1,300 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 110 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51422", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51422-M", "51422 M" ], "locale_variants": {} }, { "sku": "51124", "brand": "SKF", "manufacturer_designation": "51124", "series": "51100-series", "type": "thrust_ball", "d_mm": 120, "D_mm": 155, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 85.2, "static_load_kN": 305, "fatigue_load_limit_kN": 9.65, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51124 is a SKF single-direction thrust ball bearing for a 120 mm seat, built to ISO 104, with a flat housing seating surface, 120×155×25 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 24 decodes to 120 mm (code 24 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 120×155×25 mm (4.724×6.102×0.984 in), 17.5 mm radial section, C 85.2 kN, C0 305 kN, Pu 9.65 kN. reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical), catalogue mass 1150 g. Track-circle loading: per millimetre of mean track circumference the 85.2 kN dynamic rating corresponds to roughly 0.20 kN/mm of π·dm track, a useful comparison against the other dimension series of the 120 mm bore. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.58 at the 3,000 r/min limiting speed raises the required axial preload to about 98.7 kN; the reference-speed value 53.1 kN is the thermal design point. Speed band width for this size is 800 r/min between reference and limiting (1.36× ratio); lubrication, preload and heat removal decide where inside that band 51124 can actually run. Load balance: C0 305 kN against C 85.2 kN gives a 3.58 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 9.65 kN enters the adjusted-life check. Speed-ratio note for this exact unit: the reference speed is 2,200 r/min against a 3,000 r/min limiting speed, a reference-to-limit ratio of 0.73. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 25 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 85.2 kN C.", "applications": [ "very heavy crane and ladle hooks", "large press rams and screwdown mechanisms", "offshore and dock winch drums" ], "failure_modes": [ "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "cage damage from mounting force applied through the balls instead of the washer face", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.58; for 51124 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 120 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "When the housing seat cannot be machined square to the 120 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "The 51124 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 120 mm shaft has to be carried by a radial bearing mounted alongside it.", "Ordering discipline for 51124: the catalogue page quotes 51124 and its 85.2/305 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51124?", "a": "Boundary dimensions to ISO 104: bore 120 mm, OD 155 mm, height 25 mm; weight 1150 g. Load figures from SKF 17000: dynamic 85.2 kN, static 305 kN, fatigue limit 9.65 kN; reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical)." }, { "q": "What does the designation 51124 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 24 decodes to 120 mm (code 24 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can 51124 carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 120 mm shaft must go to a separate radial bearing; mixed loading through 51124 edge-loads the balls and destroys the washers." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." } ], "cross_ref": [ { "equiv_sku": "51124-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "51124", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51124" ], "locale_variants": {} }, { "sku": "51224", "brand": "SKF", "manufacturer_designation": "51224", "series": "51200-series", "type": "thrust_ball", "d_mm": 120, "D_mm": 170, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 127, "static_load_kN": 390, "fatigue_load_limit_kN": 11.8, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 2650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51200 series order number 51224 is a SKF single-direction thrust ball bearing for a 120 mm seat, built to ISO 104, with a flat housing seating surface, 120×170×39 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 24 decodes to 120 mm (code 24 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 120×170×39 mm (4.724×6.693×1.535 in), 25.0 mm radial section, C 127 kN, C0 390 kN, Pu 11.8 kN. reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical), catalogue mass 2650 g. Rating split for documentation: dynamic 127 kN (L10 life), static 390 kN (safety factor s0), fatigue limit 11.8 kN (adjusted life) — three different uses of three different numbers for 51224, none interchangeable with another. Speed-ratio note for this exact unit: the reference speed is 1,600 r/min against a 2,200 r/min limiting speed, a reference-to-limit ratio of 0.73. Capacity density: 127 kN C from 2.650 kg of bearing steel gives about 47.9 kN per kilogram; static density is correspondingly 147.2 kN/kg at C0 390 kN. Minimum-load arithmetic: with dm ≈ 145.0 mm and factor A 1, Fam ≈ A·(n·dm/1000)² at the 1,600 r/min reference speed is about 53.8 kN for 51224; below that preload the balls skid and smear the tracks. Track-circle loading: per millimetre of mean track circumference the 127 kN dynamic rating corresponds to roughly 0.28 kN/mm of π·dm track, a useful comparison against the other dimension series of the 120 mm bore. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 39 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 127 kN C.", "applications": [ "marine gearbox thrust positions", "large press rams and screwdown mechanisms", "very heavy crane and ladle hooks" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 39 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 1; for 51224 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "When the housing seat cannot be machined square to the 120 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 127 kN track before first rotation.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51224 as the single flat pressed steel execution; other order numbers of the 51224 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51224?", "a": "Boundary dimensions to ISO 104: bore 120 mm, OD 170 mm, height 39 mm; weight 2650 g. Load figures from SKF 17000: dynamic 127 kN, static 390 kN, fatigue limit 11.8 kN; reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical)." }, { "q": "What does the designation 51224 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 24 decodes to 120 mm (code 24 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." }, { "q": "Can 51224 carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 120 mm shaft must go to a separate radial bearing; mixed loading through 51224 edge-loads the balls and destroys the washers." } ], "cross_ref": [ { "equiv_sku": "51224-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 120×170×39 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51224", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51224" ], "locale_variants": {} }, { "sku": "51324-M", "brand": "SKF", "manufacturer_designation": "51324 M", "series": "51300-series", "type": "thrust_ball", "d_mm": 120, "D_mm": 210, "B_mm": 70, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 325, "static_load_kN": 980, "fatigue_load_limit_kN": 28.5, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1500, "max_rpm": 1500, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51324 M is SKF's 120 mm-bore single-direction thrust ball bearing in the 51300 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 120×210×70 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 24 encode the bore as 120 mm (code 24 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 120×210×70 mm (4.724×8.268×2.756 in), 45.0 mm radial section, C 325 kN, C0 980 kN, Pu 28.5 kN. reference speed 1,100 r/min (thermal) and limiting speed 1,500 r/min (mechanical), catalogue mass 11000 g. Pitch-diameter arithmetic: dm = (120+210)/2 = 165.0 mm; at the 1,500 r/min limiting speed that corresponds to roughly 248k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Speed-ratio note for this exact unit: the reference speed is 1,100 r/min against a 1,500 r/min limiting speed, a reference-to-limit ratio of 0.73. Envelope economics: the 70 mm axial height over a 45.0 mm radial section yields 4.6 kN of dynamic capacity per height millimetre, and the bearing weighs 11000 g for 325 kN C — about 34 g per rated kN. Light-load floor: Pu = 28.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51324 M; the number is 9 % of the 325 kN dynamic rating. Static-first selection data: 980 kN C0 spread across the 70 mm stack gives 14.0 kN of static rating per height millimetre, and the 11000 g mass/C0 ratio is about 11 g per static kN — crane-hook and screw positions are normally sized on these two figures. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 11000 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 120 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "offshore and dock winch drums", "heavy converter and ladle-tilt pivots", "large press rams and screwdown mechanisms" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "pitting on one track sector from a perpetually eccentric thrust line", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "overheating from grease overfill churning inside a sealed housing recess with no escape volume" ], "pitfalls": [ "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 120 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 70 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "When the housing seat cannot be machined square to the 120 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51300 bearing.", "The 325/980 kN figures belong to 51324 M specifically (the single flat brass execution of 51324); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51324-M?", "a": "51324 M measures 120 mm bore × 210 mm OD × 70 mm bearing height (4.724 × 8.268 × 2.756 in), mass about 11000 g. SKF 17000 ratings: C 325 kN, C0 980 kN, Pu 28.5 kN, reference speed 1,100 r/min (thermal) and limiting speed 1,500 r/min (mechanical)." }, { "q": "What does the designation 51324 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 24 encode the bore as 120 mm (code 24 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 120 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51324 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51324", "equiv_brand": "NTN", "level": "partial", "note": "Same 120×210×70 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51324", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51324-M", "51324 M" ], "locale_variants": {} }, { "sku": "51424-M", "brand": "SKF", "manufacturer_designation": "51424 M", "series": "51400-series", "type": "thrust_ball", "d_mm": 120, "D_mm": 250, "B_mm": 102, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 432, "static_load_kN": 1320, "fatigue_load_limit_kN": 36, "reference_speed_rpm": 800, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 25500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51424 M is an ISO 104 single-direction thrust ball bearing, 120 mm bore and 250 mm OD on a flat housing seat, standing 102 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 24: bore 120 mm (code 24 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. Envelope 120×250×102 mm (4.724×9.843×4.016 in), 65.0 mm radial section, C 432 kN, C0 1320 kN, Pu 36 kN. reference speed 800 r/min (thermal) and limiting speed 1,100 r/min (mechanical), catalogue mass 25500 g. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 16 at the 1,100 r/min limiting speed raises the required axial preload to about 662.6 kN; the reference-speed value 350.5 kN is the thermal design point. Load balance: C0 1320 kN against C 432 kN gives a 3.06 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 36 kN enters the adjusted-life check. Bore-to-OD planning: OD 250 over bore 120 is a 2.08× step for this size, and the 102 mm height gives a bore/height ratio of 1.18; use these ratios when the housing recess around the 120 mm shaft is the first constraint. Minimum-load arithmetic: with dm ≈ 185.0 mm and factor A 16, Fam ≈ A·(n·dm/1000)² at the 800 r/min reference speed is about 350.5 kN for 51424 M; below that preload the balls skid and smear the tracks. Sizing arithmetic on the 120 mm bore: 432 kN C over the 65.0 mm radial section gives 6.6 kN per section millimetre, and the 102 mm stack height is 1.57× that section — proportions typical of a 51400 thrust section. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51424 M adds a small amount of mass and cage strength without changing the 120×250×102 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,100 r/min ceiling.", "applications": [ "very heavy crane and ladle hooks", "large press rams and screwdown mechanisms", "offshore and dock winch drums" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "cage damage from mounting force applied through the balls instead of the washer face", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 16; for 51424 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51424 against two-way load lifts the loose washer off its raceway.", "The 51424 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 120 mm shaft has to be carried by a radial bearing mounted alongside it.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Ordering discipline for 51424: the catalogue page quotes 51424 M and its 432/1320 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51424-M?", "a": "The catalogue envelope is 120×250×102 mm, mass 25500 g; ratings C 432 kN / C0 1320 kN / Pu 36 kN, reference speed 800 r/min (thermal) and limiting speed 1,100 r/min (mechanical)." }, { "q": "What does the designation 51424 M mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 24: bore 120 mm (code 24 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can 51424-M carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 120 mm shaft must go to a separate radial bearing; mixed loading through 51424 M edge-loads the balls and destroys the washers." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." } ], "cross_ref": [ { "equiv_sku": "51424", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51424-M", "51424 M" ], "locale_variants": {} }, { "sku": "51126", "brand": "SKF", "manufacturer_designation": "51126", "series": "51100-series", "type": "thrust_ball", "d_mm": 130, "D_mm": 170, "B_mm": 30, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 119, "static_load_kN": 440, "fatigue_load_limit_kN": 13.4, "reference_speed_rpm": 1900, "limiting_speed_rpm": 2600, "max_rpm": 2600, "weight_g": 1850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51126 is SKF's 130 mm-bore single-direction thrust ball bearing in the 51100 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 130×170×30 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 26 encode the bore as 130 mm (code 26 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 130×170×30 mm (5.118×6.693×1.181 in), 20.0 mm radial section, C 119 kN, C0 440 kN, Pu 13.4 kN. reference speed 1,900 r/min (thermal) and limiting speed 2,600 r/min (mechanical), catalogue mass 1850 g. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.94 at the 2,600 r/min limiting speed raises the required axial preload to about 143.0 kN; the reference-speed value 76.4 kN is the thermal design point. Mass and section check: 1850 g inside the 130×170×30 mm outline leaves a 20.0 mm radial section, and the 440 kN static rating is 3.70× the dynamic rating — plan static safety and minimum preload against those figures. At the printed limiting speed of 2,600 r/min the mean pitch diameter dm ≈ 150.0 mm implies a dn value around 390k mm·r/min; the 1,900 r/min reference speed is the thermal-planning value under catalogue load. Sizing arithmetic on the 130 mm bore: 119 kN C over the 20.0 mm radial section gives 6.0 kN per section millimetre, and the 30 mm stack height is 1.50× that section — proportions typical of a 51100 thrust section. Speed band width for this size is 700 r/min between reference and limiting (1.37× ratio); lubrication, preload and heat removal decide where inside that band 51126 can actually run. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 130 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 119/440 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "offshore and dock winch drums", "heavy converter and ladle-tilt pivots", "large press rams and screwdown mechanisms" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "washer face scoring from swarf trapped between the loose housing washer and its register", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "The 51126 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 130 mm shaft has to be carried by a radial bearing mounted alongside it.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 119/440 kN and the available 170 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 119 kN track before first rotation.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51126 as the single flat pressed steel execution; other order numbers of the 51126 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51126?", "a": "51126 measures 130 mm bore × 170 mm OD × 30 mm bearing height (5.118 × 6.693 × 1.181 in), mass about 1850 g. SKF 17000 ratings: C 119 kN, C0 440 kN, Pu 13.4 kN, reference speed 1,900 r/min (thermal) and limiting speed 2,600 r/min (mechanical)." }, { "q": "What does the designation 51126 mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 26 encode the bore as 130 mm (code 26 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51126 need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 0.94 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51126-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 130×170×30 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51126", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51126" ], "locale_variants": {} }, { "sku": "51226", "brand": "SKF", "manufacturer_designation": "51226", "series": "51200-series", "type": "thrust_ball", "d_mm": 130, "D_mm": 190, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 186, "static_load_kN": 585, "fatigue_load_limit_kN": 17, "reference_speed_rpm": 1400, "limiting_speed_rpm": 2000, "max_rpm": 2000, "weight_g": 4000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51226 is an ISO 104 single-direction thrust ball bearing, 130 mm bore and 190 mm OD on a flat housing seat, standing 45 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 26: bore 130 mm (code 26 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 130×190×45 mm (5.118×7.48×1.772 in), 30.0 mm radial section, C 186 kN, C0 585 kN, Pu 17 kN. reference speed 1,400 r/min (thermal) and limiting speed 2,000 r/min (mechanical), catalogue mass 4000 g. At the printed limiting speed of 2,000 r/min the mean pitch diameter dm ≈ 160.0 mm implies a dn value around 320k mm·r/min; the 1,400 r/min reference speed is the thermal-planning value under catalogue load. Selection figures for 51226: the C0/C ratio is 3.15, Pu 17 kN is about 9 % of C, and the catalogue mass works out to roughly 31 g per millimetre of bore; the printed minimum-load factor is A 1.8. Mass and section check: 4000 g inside the 130×190×45 mm outline leaves a 30.0 mm radial section, and the 585 kN static rating is 3.15× the dynamic rating — plan static safety and minimum preload against those figures. Imperial cross-check for procurement drawings: 5.118 in bore, 7.48 in OD, 1.772 in height, and the 4000 g catalogue mass converts to 4.000 kg (141.1 oz). Rating split for documentation: dynamic 186 kN (L10 life), static 585 kN (safety factor s0), fatigue limit 17 kN (adjusted life) — three different uses of three different numbers for 51226, none interchangeable with another. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 130 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 186/585 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "marine gearbox thrust positions", "large press rams and screwdown mechanisms", "heavy converter and ladle-tilt pivots" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 186 kN track before first rotation.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 186/585 kN and the available 190 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The 51226 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 130 mm shaft has to be carried by a radial bearing mounted alongside it.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 1.8; for 51226 a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The 186/585 kN figures belong to 51226 specifically (the single flat pressed steel execution of 51226); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51226?", "a": "The catalogue envelope is 130×190×45 mm, mass 4000 g; ratings C 186 kN / C0 585 kN / Pu 17 kN, reference speed 1,400 r/min (thermal) and limiting speed 2,000 r/min (mechanical)." }, { "q": "What does the designation 51226 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 26: bore 130 mm (code 26 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." }, { "q": "How is 51226 lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 2,000 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "51226-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "51226", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51226" ], "locale_variants": {} }, { "sku": "51326-M", "brand": "SKF", "manufacturer_designation": "51326 M", "series": "51300-series", "type": "thrust_ball", "d_mm": 130, "D_mm": 225, "B_mm": 75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 358, "static_load_kN": 1140, "fatigue_load_limit_kN": 32, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1400, "max_rpm": 1400, "weight_g": 13000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51300 series order number 51326 M is a SKF single-direction thrust ball bearing for a 130 mm seat, built to ISO 104, with a flat housing seating surface, 130×225×75 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 26 decodes to 130 mm (code 26 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 130×225×75 mm (5.118×8.858×2.953 in), 47.5 mm radial section, C 358 kN, C0 1140 kN, Pu 32 kN. reference speed 1,000 r/min (thermal) and limiting speed 1,400 r/min (mechanical), catalogue mass 13000 g. Load balance: C0 1140 kN against C 358 kN gives a 3.18 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 32 kN enters the adjusted-life check. At the printed limiting speed of 1,400 r/min the mean pitch diameter dm ≈ 177.5 mm implies a dn value around 249k mm·r/min; the 1,000 r/min reference speed is the thermal-planning value under catalogue load. Sizing arithmetic on the 130 mm bore: 358 kN C over the 47.5 mm radial section gives 7.5 kN per section millimetre, and the 75 mm stack height is 1.58× that section — proportions typical of a 51300 thrust section. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 6.8 at the 1,400 r/min limiting speed raises the required axial preload to about 419.9 kN; the reference-speed value 214.2 kN is the thermal design point. Bore-to-OD planning: OD 225 over bore 130 is a 1.73× step for this size, and the 75 mm height gives a bore/height ratio of 1.73; use these ratios when the housing recess around the 130 mm shaft is the first constraint. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 13000 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 130 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "offshore and dock winch drums", "very heavy crane and ladle hooks", "marine gearbox thrust positions" ], "failure_modes": [ "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 6.8; for 51326 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The 51326 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 130 mm shaft has to be carried by a radial bearing mounted alongside it.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 358/1140 kN and the available 225 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 130 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Ordering discipline for 51326: the catalogue page quotes 51326 M and its 358/1140 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51326-M?", "a": "Boundary dimensions to ISO 104: bore 130 mm, OD 225 mm, height 75 mm; weight 13000 g. Load figures from SKF 17000: dynamic 358 kN, static 1140 kN, fatigue limit 32 kN; reference speed 1,000 r/min (thermal) and limiting speed 1,400 r/min (mechanical)." }, { "q": "What does the designation 51326 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 26 decodes to 130 mm (code 26 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51326-M?", "a": "The 1,000 r/min reference speed is the thermal balance under catalogue load; the 1,400 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51326-M need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 6.8 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51326", "equiv_brand": "NTN", "level": "partial", "note": "Same 130×225×75 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51326", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51326-M", "51326 M" ], "locale_variants": {} }, { "sku": "51426-M", "brand": "SKF", "manufacturer_designation": "51426 M", "series": "51400-series", "type": "thrust_ball", "d_mm": 130, "D_mm": 270, "B_mm": 110, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 520, "static_load_kN": 1730, "fatigue_load_limit_kN": 45, "reference_speed_rpm": 750, "limiting_speed_rpm": 1000, "max_rpm": 1000, "weight_g": 32000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51426 M is SKF's 130 mm-bore single-direction thrust ball bearing in the 51400 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 130×270×110 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 26 encode the bore as 130 mm (code 26 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 130×270×110 mm (5.118×10.63×4.331 in), 70.0 mm radial section, C 520 kN, C0 1730 kN, Pu 45 kN. reference speed 750 r/min (thermal) and limiting speed 1,000 r/min (mechanical), catalogue mass 32000 g. Load balance: C0 1730 kN against C 520 kN gives a 3.33 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 45 kN enters the adjusted-life check. Capacity density: 520 kN C from 32.000 kg of bearing steel gives about 16.3 kN per kilogram; static density is correspondingly 54.1 kN/kg at C0 1730 kN. Imperial cross-check for procurement drawings: 5.118 in bore, 10.63 in OD, 4.331 in height, and the 32000 g catalogue mass converts to 32.000 kg (1128.7 oz). Mass and section check: 32000 g inside the 130×270×110 mm outline leaves a 70.0 mm radial section, and the 1730 kN static rating is 3.33× the dynamic rating — plan static safety and minimum preload against those figures. Rating split for documentation: dynamic 520 kN (L10 life), static 1730 kN (safety factor s0), fatigue limit 45 kN (adjusted life) — three different uses of three different numbers for 51426 M, none interchangeable with another. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51426 M adds a small amount of mass and cage strength without changing the 130×270×110 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,000 r/min ceiling.", "applications": [ "very heavy crane and ladle hooks", "offshore and dock winch drums", "heavy converter and ladle-tilt pivots" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "track rust staining from condensate during long idle periods in humid plant air", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 110 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 130 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 520 kN track before first rotation.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51426 M as the single flat brass execution; other order numbers of the 51426 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51426-M?", "a": "51426 M measures 130 mm bore × 270 mm OD × 110 mm bearing height (5.118 × 10.63 × 4.331 in), mass about 32000 g. SKF 17000 ratings: C 520 kN, C0 1730 kN, Pu 45 kN, reference speed 750 r/min (thermal) and limiting speed 1,000 r/min (mechanical)." }, { "q": "What does the designation 51426 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 26 encode the bore as 130 mm (code 26 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51426-M need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 16 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number is a different, M-cage product) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51426", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51426-M", "51426 M" ], "locale_variants": {} }, { "sku": "51128", "brand": "SKF", "manufacturer_designation": "51128", "series": "51100-series", "type": "thrust_ball", "d_mm": 140, "D_mm": 180, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 111, "static_load_kN": 440, "fatigue_load_limit_kN": 12.9, "reference_speed_rpm": 1800, "limiting_speed_rpm": 2600, "max_rpm": 2600, "weight_g": 2050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51128 is a SKF single-direction thrust ball bearing for a 140 mm seat, built to ISO 104, with a flat housing seating surface, 140×180×31 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 28 decodes to 140 mm (code 28 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 140×180×31 mm (5.512×7.087×1.22 in), 20.0 mm radial section, C 111 kN, C0 440 kN, Pu 12.9 kN. reference speed 1,800 r/min (thermal) and limiting speed 2,600 r/min (mechanical), catalogue mass 2050 g. Stack/annulus proportions: the 31 mm axial stack over the 10,053 mm² washer annulus gives 3.08 mm of height per annular square millimetre ×10⁻³, and at 2050 g the bearing holds about 214.6 kN of C0 per kilogram. Pitch-diameter arithmetic: dm = (140+180)/2 = 160.0 mm; at the 2,600 r/min limiting speed that corresponds to roughly 416k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Section proportions: the 20.0 mm radial section compares with 140 mm of bore (section/bore ≈ 0.14) and the 31 mm height is 1.55× that section — the proportions that identify the 51100 envelope at a glance. Rating split for documentation: dynamic 111 kN (L10 life), static 440 kN (safety factor s0), fatigue limit 12.9 kN (adjusted life) — three different uses of three different numbers for 51128, none interchangeable with another. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 1 at the 2,600 r/min limiting speed raises the required axial preload to about 173.1 kN; the reference-speed value 82.9 kN is the thermal design point. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 140 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 111/440 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "marine gearbox thrust positions", "heavy converter and ladle-tilt pivots", "large press rams and screwdown mechanisms" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "washer face scoring from swarf trapped between the loose housing washer and its register", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 31 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The 51128 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 140 mm shaft has to be carried by a radial bearing mounted alongside it.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 111/440 kN and the available 180 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51128 as the single flat pressed steel execution; other order numbers of the 51128 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51128?", "a": "Boundary dimensions to ISO 104: bore 140 mm, OD 180 mm, height 31 mm; weight 2050 g. Load figures from SKF 17000: dynamic 111 kN, static 440 kN, fatigue limit 12.9 kN; reference speed 1,800 r/min (thermal) and limiting speed 2,600 r/min (mechanical)." }, { "q": "What does the designation 51128 mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 28 decodes to 140 mm (code 28 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can a single 51128 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." }, { "q": "What do the two published speeds mean for 51128?", "a": "The 1,800 r/min reference speed is the thermal balance under catalogue load; the 2,600 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." } ], "cross_ref": [ { "equiv_sku": "51128-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 140×180×31 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51128", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51128" ], "locale_variants": {} }, { "sku": "51228", "brand": "SKF", "manufacturer_designation": "51228", "series": "51200-series", "type": "thrust_ball", "d_mm": 140, "D_mm": 200, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 190, "static_load_kN": 620, "fatigue_load_limit_kN": 17.6, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1900, "max_rpm": 1900, "weight_g": 4350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51228 is an ISO 104 single-direction thrust ball bearing, 140 mm bore and 200 mm OD on a flat housing seat, standing 46 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 28: bore 140 mm (code 28 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 140×200×46 mm (5.512×7.874×1.811 in), 30.0 mm radial section, C 190 kN, C0 620 kN, Pu 17.6 kN. reference speed 1,400 r/min (thermal) and limiting speed 1,900 r/min (mechanical), catalogue mass 4350 g. Imperial cross-check for procurement drawings: 5.512 in bore, 7.874 in OD, 1.811 in height, and the 4350 g catalogue mass converts to 4.350 kg (153.4 oz). Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 1,900 r/min while thermal balance under catalogue load sets the 1,400 r/min reference; at dm ≈ 170.0 mm the corresponding dn is approximately 323k mm·r/min. At the printed limiting speed of 1,900 r/min the mean pitch diameter dm ≈ 170.0 mm implies a dn value around 323k mm·r/min; the 1,400 r/min reference speed is the thermal-planning value under catalogue load. Stack/annulus proportions: the 46 mm axial stack over the 16,022 mm² washer annulus gives 2.87 mm of height per annular square millimetre ×10⁻³, and at 4350 g the bearing holds about 142.5 kN of C0 per kilogram. Track-circle loading: per millimetre of mean track circumference the 190 kN dynamic rating corresponds to roughly 0.36 kN/mm of π·dm track, a useful comparison against the other dimension series of the 140 mm bore. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. On this 140 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 190/620 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.", "applications": [ "offshore and dock winch drums", "marine gearbox thrust positions", "very heavy crane and ladle hooks" ], "failure_modes": [ "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "pressed sheet-steel cage distortion after a mounting blow or shock load at sizes where the F/M machined-cage executions are the catalogue choice", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "When the housing seat cannot be machined square to the 140 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "The 51228 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 140 mm shaft has to be carried by a radial bearing mounted alongside it.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51228 against two-way load lifts the loose washer off its raceway.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 190 kN track before first rotation.", "Ordering discipline for 51228: the catalogue page quotes 51228 and its 190/620 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51228?", "a": "The catalogue envelope is 140×200×46 mm, mass 4350 g; ratings C 190 kN / C0 620 kN / Pu 17.6 kN, reference speed 1,400 r/min (thermal) and limiting speed 1,900 r/min (mechanical)." }, { "q": "What does the designation 51228 mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 28: bore 140 mm (code 28 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 140 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51228 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51228-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "51228", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51228" ], "locale_variants": {} }, { "sku": "51328-M", "brand": "SKF", "manufacturer_designation": "51328 M", "series": "51300-series", "type": "thrust_ball", "d_mm": 140, "D_mm": 240, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 377, "static_load_kN": 1220, "fatigue_load_limit_kN": 32.5, "reference_speed_rpm": 950, "limiting_speed_rpm": 1300, "max_rpm": 1300, "weight_g": 15500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51300 series order number 51328 M is a SKF single-direction thrust ball bearing for a 140 mm seat, built to ISO 104, with a flat housing seating surface, 140×240×80 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 28 decodes to 140 mm (code 28 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 140×240×80 mm (5.512×9.449×3.15 in), 50.0 mm radial section, C 377 kN, C0 1220 kN, Pu 32.5 kN. reference speed 950 r/min (thermal) and limiting speed 1,300 r/min (mechanical), catalogue mass 15500 g. Bore-to-OD planning: OD 240 over bore 140 is a 1.71× step for this size, and the 80 mm height gives a bore/height ratio of 1.75; use these ratios when the housing recess around the 140 mm shaft is the first constraint. Section proportions: the 50.0 mm radial section compares with 140 mm of bore (section/bore ≈ 0.36) and the 80 mm height is 1.60× that section — the proportions that identify the 51300 envelope at a glance. Minimum-load arithmetic: with dm ≈ 190.0 mm and factor A 9.1, Fam ≈ A·(n·dm/1000)² at the 950 r/min reference speed is about 296.5 kN for 51328 M; below that preload the balls skid and smear the tracks. At the printed limiting speed of 1,300 r/min the mean pitch diameter dm ≈ 190.0 mm implies a dn value around 247k mm·r/min; the 950 r/min reference speed is the thermal-planning value under catalogue load. Pitch-diameter arithmetic: dm = (140+240)/2 = 190.0 mm; at the 1,300 r/min limiting speed that corresponds to roughly 247k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51328 M adds a small amount of mass and cage strength without changing the 140×240×80 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,300 r/min ceiling.", "applications": [ "offshore and dock winch drums", "very heavy crane and ladle hooks", "heavy converter and ladle-tilt pivots" ], "failure_modes": [ "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 80 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 377/1220 kN and the available 240 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The 51328 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 140 mm shaft has to be carried by a radial bearing mounted alongside it.", "The 377/1220 kN figures belong to 51328 M specifically (the single flat brass execution of 51328); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51328-M?", "a": "Boundary dimensions to ISO 104: bore 140 mm, OD 240 mm, height 80 mm; weight 15500 g. Load figures from SKF 17000: dynamic 377 kN, static 1220 kN, fatigue limit 32.5 kN; reference speed 950 r/min (thermal) and limiting speed 1,300 r/min (mechanical)." }, { "q": "What does the designation 51328 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 28 decodes to 140 mm (code 28 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number is a different, M-cage product) uses the standard stamped sheet-steel pressed cage." }, { "q": "Can 51328-M carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 140 mm shaft must go to a separate radial bearing; mixed loading through 51328 M edge-loads the balls and destroys the washers." } ], "cross_ref": [ { "equiv_sku": "51328", "equiv_brand": "NTN", "level": "partial", "note": "Same 140×240×80 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51328", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51328-M", "51328 M" ], "locale_variants": {} }, { "sku": "51428-M", "brand": "SKF", "manufacturer_designation": "51428 M", "series": "51400-series", "type": "thrust_ball", "d_mm": 140, "D_mm": 280, "B_mm": 112, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 520, "static_load_kN": 1730, "fatigue_load_limit_kN": 44, "reference_speed_rpm": 700, "limiting_speed_rpm": 1000, "max_rpm": 1000, "weight_g": 34500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51428 M is SKF's 140 mm-bore single-direction thrust ball bearing in the 51400 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 140×280×112 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 28 encode the bore as 140 mm (code 28 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 140×280×112 mm (5.512×11.024×4.409 in), 70.0 mm radial section, C 520 kN, C0 1730 kN, Pu 44 kN. reference speed 700 r/min (thermal) and limiting speed 1,000 r/min (mechanical), catalogue mass 34500 g. Speed band width for this size is 300 r/min between reference and limiting (1.43× ratio); lubrication, preload and heat removal decide where inside that band 51428 M can actually run. Sizing arithmetic on the 140 mm bore: 520 kN C over the 70.0 mm radial section gives 7.4 kN per section millimetre, and the 112 mm stack height is 1.60× that section — proportions typical of a 51400 thrust section. Section proportions: the 70.0 mm radial section compares with 140 mm of bore (section/bore ≈ 0.50) and the 112 mm height is 1.60× that section — the proportions that identify the 51400 envelope at a glance. Mass and section check: 34500 g inside the 140×280×112 mm outline leaves a 70.0 mm radial section, and the 1730 kN static rating is 3.33× the dynamic rating — plan static safety and minimum preload against those figures. Bore-to-OD planning: OD 280 over bore 140 is a 2.00× step for this size, and the 112 mm height gives a bore/height ratio of 1.25; use these ratios when the housing recess around the 140 mm shaft is the first constraint. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51428 M adds a small amount of mass and cage strength without changing the 140×280×112 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,000 r/min ceiling.", "applications": [ "marine gearbox thrust positions", "very heavy crane and ladle hooks", "large press rams and screwdown mechanisms" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "false brinelling of the stationary tracks while the machine stands under vibration", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 16; for 51428 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 112 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 520 kN track before first rotation.", "The 51428 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 140 mm shaft has to be carried by a radial bearing mounted alongside it.", "Ordering discipline for 51428: the catalogue page quotes 51428 M and its 520/1730 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51428-M?", "a": "51428 M measures 140 mm bore × 280 mm OD × 112 mm bearing height (5.512 × 11.024 × 4.409 in), mass about 34500 g. SKF 17000 ratings: C 520 kN, C0 1730 kN, Pu 44 kN, reference speed 700 r/min (thermal) and limiting speed 1,000 r/min (mechanical)." }, { "q": "What does the designation 51428 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 28 encode the bore as 140 mm (code 28 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can a single 51428 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." }, { "q": "What do the two published speeds mean for 51428-M?", "a": "The 700 r/min reference speed is the thermal balance under catalogue load; the 1,000 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." } ], "cross_ref": [ { "equiv_sku": "51428", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51428-M", "51428 M" ], "locale_variants": {} }, { "sku": "51130-M", "brand": "SKF", "manufacturer_designation": "51130 M", "series": "51100-series", "type": "thrust_ball", "d_mm": 150, "D_mm": 190, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 111, "static_load_kN": 440, "fatigue_load_limit_kN": 12.5, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 2200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51130 M is SKF's 150 mm-bore single-direction thrust ball bearing in the 51100 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 150×190×31 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 30 encode the bore as 150 mm (code 30 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 150×190×31 mm (5.906×7.48×1.22 in), 20.0 mm radial section, C 111 kN, C0 440 kN, Pu 12.5 kN. reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical), catalogue mass 2200 g. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51130 M covers about 10,681 mm², distributing C0 440 kN over a mean track circle of π·dm ≈ 534 mm. Rating split for documentation: dynamic 111 kN (L10 life), static 440 kN (safety factor s0), fatigue limit 12.5 kN (adjusted life) — three different uses of three different numbers for 51130 M, none interchangeable with another. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 1 at the 2,400 r/min limiting speed raises the required axial preload to about 166.5 kN; the reference-speed value 83.5 kN is the thermal design point. Load balance: C0 440 kN against C 111 kN gives a 3.96 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 12.5 kN enters the adjusted-life check. Speed-ratio note for this exact unit: the reference speed is 1,700 r/min against a 2,400 r/min limiting speed, a reference-to-limit ratio of 0.71. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 2200 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 150 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "large press rams and screwdown mechanisms", "very heavy crane and ladle hooks", "heavy converter and ladle-tilt pivots" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "false brinelling of the stationary tracks while the machine stands under vibration", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "When the housing seat cannot be machined square to the 150 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 1; for 51130 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 150 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "The 51130 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 150 mm shaft has to be carried by a radial bearing mounted alongside it.", "Ordering discipline for 51130: the catalogue page quotes 51130 M and its 111/440 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51130-M?", "a": "51130 M measures 150 mm bore × 190 mm OD × 31 mm bearing height (5.906 × 7.48 × 1.22 in), mass about 2200 g. SKF 17000 ratings: C 111 kN, C0 440 kN, Pu 12.5 kN, reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical)." }, { "q": "What does the designation 51130 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 30 encode the bore as 150 mm (code 30 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51130-M lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 2,400 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 150 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51130", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "51130", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51130-M", "51130 M" ], "locale_variants": {} }, { "sku": "51230-M", "brand": "SKF", "manufacturer_designation": "51230 M", "series": "51200-series", "type": "thrust_ball", "d_mm": 150, "D_mm": 215, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 238, "static_load_kN": 800, "fatigue_load_limit_kN": 22, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 6100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51230 M is an ISO 104 single-direction thrust ball bearing, 150 mm bore and 215 mm OD on a flat housing seat, standing 50 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 30: bore 150 mm (code 30 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. Envelope 150×215×50 mm (5.906×8.465×1.969 in), 32.5 mm radial section, C 238 kN, C0 800 kN, Pu 22 kN. reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical), catalogue mass 6100 g. Rating split for documentation: dynamic 238 kN (L10 life), static 800 kN (safety factor s0), fatigue limit 22 kN (adjusted life) — three different uses of three different numbers for 51230 M, none interchangeable with another. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51230 M covers about 18,634 mm², distributing C0 800 kN over a mean track circle of π·dm ≈ 573 mm. Light-load floor: Pu = 22 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51230 M; the number is 9 % of the 238 kN dynamic rating. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 3.3 at the 1,800 r/min limiting speed raises the required axial preload to about 356.1 kN; the reference-speed value 185.7 kN is the thermal design point. Speed-ratio note for this exact unit: the reference speed is 1,300 r/min against a 1,800 r/min limiting speed, a reference-to-limit ratio of 0.72. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 6100 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 150 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "heavy converter and ladle-tilt pivots", "very heavy crane and ladle hooks", "large press rams and screwdown mechanisms" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 50 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51230 against two-way load lifts the loose washer off its raceway.", "When the housing seat cannot be machined square to the 150 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51230 M as the single flat brass execution; other order numbers of the 51230 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51230-M?", "a": "The catalogue envelope is 150×215×50 mm, mass 6100 g; ratings C 238 kN / C0 800 kN / Pu 22 kN, reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical)." }, { "q": "What does the designation 51230 M mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 30: bore 150 mm (code 30 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51230-M?", "a": "The 1,300 r/min reference speed is the thermal balance under catalogue load; the 1,800 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51230-M need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 3.3 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51230", "equiv_brand": "NTN", "level": "partial", "note": "Same 150×215×50 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51230", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51230-M", "51230 M" ], "locale_variants": {} }, { "sku": "51330-M", "brand": "SKF", "manufacturer_designation": "51330 M", "series": "51300-series", "type": "thrust_ball", "d_mm": 150, "D_mm": 250, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 390, "static_load_kN": 1290, "fatigue_load_limit_kN": 34, "reference_speed_rpm": 900, "limiting_speed_rpm": 1300, "max_rpm": 1300, "weight_g": 16500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51300 series order number 51330 M is a SKF single-direction thrust ball bearing for a 150 mm seat, built to ISO 104, with a flat housing seating surface, 150×250×80 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 30 decodes to 150 mm (code 30 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 150×250×80 mm (5.906×9.843×3.15 in), 50.0 mm radial section, C 390 kN, C0 1290 kN, Pu 34 kN. reference speed 900 r/min (thermal) and limiting speed 1,300 r/min (mechanical), catalogue mass 16500 g. Capacity density: 390 kN C from 16.500 kg of bearing steel gives about 23.6 kN per kilogram; static density is correspondingly 78.2 kN/kg at C0 1290 kN. Pitch-diameter arithmetic: dm = (150+250)/2 = 200.0 mm; at the 1,300 r/min limiting speed that corresponds to roughly 260k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Static-first selection data: 1290 kN C0 spread across the 80 mm stack gives 16.1 kN of static rating per height millimetre, and the 16500 g mass/C0 ratio is about 13 g per static kN — crane-hook and screw positions are normally sized on these two figures. Sizing arithmetic on the 150 mm bore: 390 kN C over the 50.0 mm radial section gives 7.8 kN per section millimetre, and the 80 mm stack height is 1.60× that section — proportions typical of a 51300 thrust section. Track-circle loading: per millimetre of mean track circumference the 390 kN dynamic rating corresponds to roughly 0.62 kN/mm of π·dm track, a useful comparison against the other dimension series of the 150 mm bore. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51330 M adds a small amount of mass and cage strength without changing the 150×250×80 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,300 r/min ceiling.", "applications": [ "large press rams and screwdown mechanisms", "very heavy crane and ladle hooks", "offshore and dock winch drums" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "false brinelling of the stationary tracks while the machine stands under vibration", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 150 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 390/1290 kN and the available 250 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "When the housing seat cannot be machined square to the 150 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51300 bearing.", "The 390/1290 kN figures belong to 51330 M specifically (the single flat brass execution of 51330); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51330-M?", "a": "Boundary dimensions to ISO 104: bore 150 mm, OD 250 mm, height 80 mm; weight 16500 g. Load figures from SKF 17000: dynamic 390 kN, static 1290 kN, fatigue limit 34 kN; reference speed 900 r/min (thermal) and limiting speed 1,300 r/min (mechanical)." }, { "q": "What does the designation 51330 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 30 decodes to 150 mm (code 30 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can 51330-M carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 150 mm shaft must go to a separate radial bearing; mixed loading through 51330 M edge-loads the balls and destroys the washers." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." } ], "cross_ref": [ { "equiv_sku": "51330", "equiv_brand": "NTN", "level": "partial", "note": "Same 150×250×80 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51330", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51330-M", "51330 M" ], "locale_variants": {} }, { "sku": "51430-M", "brand": "SKF", "manufacturer_designation": "51430 M", "series": "51400-series", "type": "thrust_ball", "d_mm": 150, "D_mm": 300, "B_mm": 120, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 559, "static_load_kN": 1960, "fatigue_load_limit_kN": 48, "reference_speed_rpm": 670, "limiting_speed_rpm": 950, "max_rpm": 950, "weight_g": 42500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51400 series order number 51430 M is a SKF single-direction thrust ball bearing for a 150 mm seat, built to ISO 104, with a flat housing seating surface, 150×300×120 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 30 decodes to 150 mm (code 30 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 150×300×120 mm (5.906×11.811×4.724 in), 75.0 mm radial section, C 559 kN, C0 1960 kN, Pu 48 kN. reference speed 670 r/min (thermal) and limiting speed 950 r/min (mechanical), catalogue mass 42500 g. Envelope economics: the 120 mm axial height over a 75.0 mm radial section yields 4.7 kN of dynamic capacity per height millimetre, and the bearing weighs 42500 g for 559 kN C — about 76 g per rated kN. Selection figures for 51430 M: the C0/C ratio is 3.51, Pu 48 kN is about 9 % of C, and the catalogue mass works out to roughly 283 g per millimetre of bore; the printed minimum-load factor is A 20. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51430 M covers about 53,014 mm², distributing C0 1960 kN over a mean track circle of π·dm ≈ 707 mm. Speed band width for this size is 280 r/min between reference and limiting (1.42× ratio); lubrication, preload and heat removal decide where inside that band 51430 M can actually run. Section proportions: the 75.0 mm radial section compares with 150 mm of bore (section/bore ≈ 0.50) and the 120 mm height is 1.60× that section — the proportions that identify the 51400 envelope at a glance. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51430 M adds a small amount of mass and cage strength without changing the 150×300×120 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 950 r/min ceiling.", "applications": [ "very heavy crane and ladle hooks", "large press rams and screwdown mechanisms", "marine gearbox thrust positions" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "raceway indentation from driving the bearing home through the ball set rather than the washer face" ], "pitfalls": [ "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 150 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 20; for 51430 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "When the housing seat cannot be machined square to the 150 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51400 bearing.", "The 559/1960 kN figures belong to 51430 M specifically (the single flat brass execution of 51430); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51430-M?", "a": "Boundary dimensions to ISO 104: bore 150 mm, OD 300 mm, height 120 mm; weight 42500 g. Load figures from SKF 17000: dynamic 559 kN, static 1960 kN, fatigue limit 48 kN; reference speed 670 r/min (thermal) and limiting speed 950 r/min (mechanical)." }, { "q": "What does the designation 51430 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 30 decodes to 150 mm (code 30 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 150 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51430 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51430", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51430-M", "51430 M" ], "locale_variants": {} }, { "sku": "51132-M", "brand": "SKF", "manufacturer_designation": "51132 M", "series": "51100-series", "type": "thrust_ball", "d_mm": 160, "D_mm": 200, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 112, "static_load_kN": 465, "fatigue_load_limit_kN": 12.9, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 2350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51132 M is a SKF single-direction thrust ball bearing for a 160 mm seat, built to ISO 104, with a flat housing seating surface, 160×200×31 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 32 decodes to 160 mm (code 32 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 160×200×31 mm (6.299×7.874×1.22 in), 20.0 mm radial section, C 112 kN, C0 465 kN, Pu 12.9 kN. reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical), catalogue mass 2350 g. Envelope economics: the 31 mm axial height over a 20.0 mm radial section yields 3.6 kN of dynamic capacity per height millimetre, and the bearing weighs 2350 g for 112 kN C — about 21 g per rated kN. Rating split for documentation: dynamic 112 kN (L10 life), static 465 kN (safety factor s0), fatigue limit 12.9 kN (adjusted life) — three different uses of three different numbers for 51132 M, none interchangeable with another. Stack/annulus proportions: the 31 mm axial stack over the 11,310 mm² washer annulus gives 2.74 mm of height per annular square millimetre ×10⁻³, and at 2350 g the bearing holds about 197.9 kN of C0 per kilogram. Speed band width for this size is 700 r/min between reference and limiting (1.41× ratio); lubrication, preload and heat removal decide where inside that band 51132 M can actually run. Sizing arithmetic on the 160 mm bore: 112 kN C over the 20.0 mm radial section gives 5.6 kN per section millimetre, and the 31 mm stack height is 1.55× that section — proportions typical of a 51100 thrust section. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 2350 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 160 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "large press rams and screwdown mechanisms", "marine gearbox thrust positions", "very heavy crane and ladle hooks" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "cage damage from mounting force applied through the balls instead of the washer face", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "The 51132 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 160 mm shaft has to be carried by a radial bearing mounted alongside it.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 31 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "When the housing seat cannot be machined square to the 160 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 112/465 kN and the available 200 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51132 M as the single flat brass execution; other order numbers of the 51132 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51132-M?", "a": "Boundary dimensions to ISO 104: bore 160 mm, OD 200 mm, height 31 mm; weight 2350 g. Load figures from SKF 17000: dynamic 112 kN, static 465 kN, fatigue limit 12.9 kN; reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical)." }, { "q": "What does the designation 51132 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 32 decodes to 160 mm (code 32 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can a single 51132 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." }, { "q": "What do the two published speeds mean for 51132-M?", "a": "The 1,700 r/min reference speed is the thermal balance under catalogue load; the 2,400 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." } ], "cross_ref": [ { "equiv_sku": "51132", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "51132", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51132-M", "51132 M" ], "locale_variants": {} }, { "sku": "51232-M", "brand": "SKF", "manufacturer_designation": "51232 M", "series": "51200-series", "type": "thrust_ball", "d_mm": 160, "D_mm": 225, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 238, "static_load_kN": 830, "fatigue_load_limit_kN": 22.4, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1700, "max_rpm": 1700, "weight_g": 6550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51200 series order number 51232 M is a SKF single-direction thrust ball bearing for a 160 mm seat, built to ISO 104, with a flat housing seating surface, 160×225×51 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 32 decodes to 160 mm (code 32 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 160×225×51 mm (6.299×8.858×2.008 in), 32.5 mm radial section, C 238 kN, C0 830 kN, Pu 22.4 kN. reference speed 1,200 r/min (thermal) and limiting speed 1,700 r/min (mechanical), catalogue mass 6550 g. Capacity density: 238 kN C from 6.550 kg of bearing steel gives about 36.3 kN per kilogram; static density is correspondingly 126.7 kN/kg at C0 830 kN. Selection figures for 51232 M: the C0/C ratio is 3.49, Pu 22.4 kN is about 9 % of C, and the catalogue mass works out to roughly 41 g per millimetre of bore; the printed minimum-load factor is A 3.8. Minimum-load arithmetic: with dm ≈ 192.5 mm and factor A 3.8, Fam ≈ A·(n·dm/1000)² at the 1,200 r/min reference speed is about 202.8 kN for 51232 M; below that preload the balls skid and smear the tracks. Pitch-diameter arithmetic: dm = (160+225)/2 = 192.5 mm; at the 1,700 r/min limiting speed that corresponds to roughly 327k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Speed-ratio note for this exact unit: the reference speed is 1,200 r/min against a 1,700 r/min limiting speed, a reference-to-limit ratio of 0.71. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 6550 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 160 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "large press rams and screwdown mechanisms", "offshore and dock winch drums", "marine gearbox thrust positions" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 51 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 3.8; for 51232 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "When the housing seat cannot be machined square to the 160 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 238 kN track before first rotation.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51232 M as the single flat brass execution; other order numbers of the 51232 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51232-M?", "a": "Boundary dimensions to ISO 104: bore 160 mm, OD 225 mm, height 51 mm; weight 6550 g. Load figures from SKF 17000: dynamic 238 kN, static 830 kN, fatigue limit 22.4 kN; reference speed 1,200 r/min (thermal) and limiting speed 1,700 r/min (mechanical)." }, { "q": "What does the designation 51232 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 32 decodes to 160 mm (code 32 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 160 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51232 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51232", "equiv_brand": "NTN", "level": "partial", "note": "Same 160×225×51 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51232", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51232-M", "51232 M" ], "locale_variants": {} }, { "sku": "51332-M", "brand": "SKF", "manufacturer_designation": "51332 M", "series": "51300-series", "type": "thrust_ball", "d_mm": 160, "D_mm": 270, "B_mm": 87, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 449, "static_load_kN": 1660, "fatigue_load_limit_kN": 41.5, "reference_speed_rpm": 850, "limiting_speed_rpm": 1200, "max_rpm": 1200, "weight_g": 21000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51300 series order number 51332 M is a SKF single-direction thrust ball bearing for a 160 mm seat, built to ISO 104, with a flat housing seating surface, 160×270×87 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 32 decodes to 160 mm (code 32 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 160×270×87 mm (6.299×10.63×3.425 in), 55.0 mm radial section, C 449 kN, C0 1660 kN, Pu 41.5 kN. reference speed 850 r/min (thermal) and limiting speed 1,200 r/min (mechanical), catalogue mass 21000 g. At the printed limiting speed of 1,200 r/min the mean pitch diameter dm ≈ 215.0 mm implies a dn value around 258k mm·r/min; the 850 r/min reference speed is the thermal-planning value under catalogue load. Minimum-load arithmetic: with dm ≈ 215.0 mm and factor A 14, Fam ≈ A·(n·dm/1000)² at the 850 r/min reference speed is about 467.6 kN for 51332 M; below that preload the balls skid and smear the tracks. Light-load floor: Pu = 41.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51332 M; the number is 9 % of the 449 kN dynamic rating. Mass and section check: 21000 g inside the 160×270×87 mm outline leaves a 55.0 mm radial section, and the 1660 kN static rating is 3.70× the dynamic rating — plan static safety and minimum preload against those figures. Speed band width for this size is 350 r/min between reference and limiting (1.41× ratio); lubrication, preload and heat removal decide where inside that band 51332 M can actually run. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 21000 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 160 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "very heavy crane and ladle hooks", "offshore and dock winch drums", "heavy converter and ladle-tilt pivots" ], "failure_modes": [ "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "track rust staining from condensate during long idle periods in humid plant air", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 449 kN track before first rotation.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 87 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 449/1660 kN and the available 270 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51332 against two-way load lifts the loose washer off its raceway.", "The 449/1660 kN figures belong to 51332 M specifically (the single flat brass execution of 51332); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51332-M?", "a": "Boundary dimensions to ISO 104: bore 160 mm, OD 270 mm, height 87 mm; weight 21000 g. Load figures from SKF 17000: dynamic 449 kN, static 1660 kN, fatigue limit 41.5 kN; reference speed 850 r/min (thermal) and limiting speed 1,200 r/min (mechanical)." }, { "q": "What does the designation 51332 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 32 decodes to 160 mm (code 32 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51332-M need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 14 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number is a different, M-cage product) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51332", "equiv_brand": "NTN", "level": "partial", "note": "Same 160×270×87 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51332", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51332-M", "51332 M" ], "locale_variants": {} }, { "sku": "51134-M", "brand": "SKF", "manufacturer_designation": "51134 M", "series": "51100-series", "type": "thrust_ball", "d_mm": 170, "D_mm": 215, "B_mm": 34, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 133, "static_load_kN": 540, "fatigue_load_limit_kN": 14.3, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 3300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51134 M is a SKF single-direction thrust ball bearing for a 170 mm seat, built to ISO 104, with a flat housing seating surface, 170×215×34 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 34 decodes to 170 mm (code 34 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 170×215×34 mm (6.693×8.465×1.339 in), 22.5 mm radial section, C 133 kN, C0 540 kN, Pu 14.3 kN. reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical), catalogue mass 3300 g. Envelope economics: the 34 mm axial height over a 22.5 mm radial section yields 3.9 kN of dynamic capacity per height millimetre, and the bearing weighs 3300 g for 133 kN C — about 25 g per rated kN. Capacity density: 133 kN C from 3.300 kg of bearing steel gives about 40.3 kN per kilogram; static density is correspondingly 163.6 kN/kg at C0 540 kN. Pitch-diameter arithmetic: dm = (170+215)/2 = 192.5 mm; at the 2,200 r/min limiting speed that corresponds to roughly 424k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Track-circle loading: per millimetre of mean track circumference the 133 kN dynamic rating corresponds to roughly 0.22 kN/mm of π·dm track, a useful comparison against the other dimension series of the 170 mm bore. Minimum-load arithmetic: with dm ≈ 192.5 mm and factor A 1.5, Fam ≈ A·(n·dm/1000)² at the 1,600 r/min reference speed is about 142.3 kN for 51134 M; below that preload the balls skid and smear the tracks. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 3300 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 170 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "marine gearbox thrust positions", "very heavy crane and ladle hooks", "offshore and dock winch drums" ], "failure_modes": [ "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "false brinelling of the stationary tracks while the machine stands under vibration", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 170 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 133/540 kN and the available 215 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 1.5; for 51134 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The 133/540 kN figures belong to 51134 M specifically (the single flat brass execution of 51134); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51134-M?", "a": "Boundary dimensions to ISO 104: bore 170 mm, OD 215 mm, height 34 mm; weight 3300 g. Load figures from SKF 17000: dynamic 133 kN, static 540 kN, fatigue limit 14.3 kN; reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical)." }, { "q": "What does the designation 51134 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 34 decodes to 170 mm (code 34 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51134-M need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 1.5 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number is a different, M-cage product) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51134", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "51134", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51134-M", "51134 M" ], "locale_variants": {} }, { "sku": "51234-M", "brand": "SKF", "manufacturer_designation": "51234 M", "series": "51200-series", "type": "thrust_ball", "d_mm": 170, "D_mm": 240, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 270, "static_load_kN": 930, "fatigue_load_limit_kN": 24, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1700, "max_rpm": 1700, "weight_g": 8150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51234 M is SKF's 170 mm-bore single-direction thrust ball bearing in the 51200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 170×240×55 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 34 encode the bore as 170 mm (code 34 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 170×240×55 mm (6.693×9.449×2.165 in), 35.0 mm radial section, C 270 kN, C0 930 kN, Pu 24 kN. reference speed 1,200 r/min (thermal) and limiting speed 1,700 r/min (mechanical), catalogue mass 8150 g. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 5.4 at the 1,700 r/min limiting speed raises the required axial preload to about 655.8 kN; the reference-speed value 326.8 kN is the thermal design point. Section proportions: the 35.0 mm radial section compares with 170 mm of bore (section/bore ≈ 0.21) and the 55 mm height is 1.57× that section — the proportions that identify the 51200 envelope at a glance. Mass and section check: 8150 g inside the 170×240×55 mm outline leaves a 35.0 mm radial section, and the 930 kN static rating is 3.44× the dynamic rating — plan static safety and minimum preload against those figures. Capacity density: 270 kN C from 8.150 kg of bearing steel gives about 33.1 kN per kilogram; static density is correspondingly 114.1 kN/kg at C0 930 kN. Track-circle loading: per millimetre of mean track circumference the 270 kN dynamic rating corresponds to roughly 0.42 kN/mm of π·dm track, a useful comparison against the other dimension series of the 170 mm bore. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 8150 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 170 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "large press rams and screwdown mechanisms", "very heavy crane and ladle hooks", "offshore and dock winch drums" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "When the housing seat cannot be machined square to the 170 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 170 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 270 kN track before first rotation.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 55 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Ordering discipline for 51234: the catalogue page quotes 51234 M and its 270/930 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51234-M?", "a": "51234 M measures 170 mm bore × 240 mm OD × 55 mm bearing height (6.693 × 9.449 × 2.165 in), mass about 8150 g. SKF 17000 ratings: C 270 kN, C0 930 kN, Pu 24 kN, reference speed 1,200 r/min (thermal) and limiting speed 1,700 r/min (mechanical)." }, { "q": "What does the designation 51234 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 34 encode the bore as 170 mm (code 34 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." }, { "q": "How is 51234-M lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 1,700 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "51234", "equiv_brand": "NTN", "level": "partial", "note": "Same 170×240×55 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51234", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51234-M", "51234 M" ], "locale_variants": {} }, { "sku": "51334-M", "brand": "SKF", "manufacturer_designation": "51334 M", "series": "51300-series", "type": "thrust_ball", "d_mm": 170, "D_mm": 280, "B_mm": 87, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 468, "static_load_kN": 1760, "fatigue_load_limit_kN": 43, "reference_speed_rpm": 800, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 22000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51334 M is SKF's 170 mm-bore single-direction thrust ball bearing in the 51300 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 170×280×87 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 34 encode the bore as 170 mm (code 34 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 170×280×87 mm (6.693×11.024×3.425 in), 55.0 mm radial section, C 468 kN, C0 1760 kN, Pu 43 kN. reference speed 800 r/min (thermal) and limiting speed 1,100 r/min (mechanical), catalogue mass 22000 g. Envelope economics: the 87 mm axial height over a 55.0 mm radial section yields 5.4 kN of dynamic capacity per height millimetre, and the bearing weighs 22000 g for 468 kN C — about 47 g per rated kN. Stack/annulus proportions: the 87 mm axial stack over the 38,877 mm² washer annulus gives 2.24 mm of height per annular square millimetre ×10⁻³, and at 22000 g the bearing holds about 80.0 kN of C0 per kilogram. Minimum-load arithmetic: with dm ≈ 225.0 mm and factor A 16, Fam ≈ A·(n·dm/1000)² at the 800 r/min reference speed is about 518.4 kN for 51334 M; below that preload the balls skid and smear the tracks. Mass and section check: 22000 g inside the 170×280×87 mm outline leaves a 55.0 mm radial section, and the 1760 kN static rating is 3.76× the dynamic rating — plan static safety and minimum preload against those figures. Light-load floor: Pu = 43 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51334 M; the number is 9 % of the 468 kN dynamic rating. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 22000 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 170 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "large press rams and screwdown mechanisms", "offshore and dock winch drums", "heavy converter and ladle-tilt pivots" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "track rust staining from condensate during long idle periods in humid plant air", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 468/1760 kN and the available 280 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 170 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "When the housing seat cannot be machined square to the 170 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51300 bearing.", "The 468/1760 kN figures belong to 51334 M specifically (the single flat brass execution of 51334); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51334-M?", "a": "51334 M measures 170 mm bore × 280 mm OD × 87 mm bearing height (6.693 × 11.024 × 3.425 in), mass about 22000 g. SKF 17000 ratings: C 468 kN, C0 1760 kN, Pu 43 kN, reference speed 800 r/min (thermal) and limiting speed 1,100 r/min (mechanical)." }, { "q": "What does the designation 51334 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 34 encode the bore as 170 mm (code 34 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can a single 51334 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." }, { "q": "What do the two published speeds mean for 51334-M?", "a": "The 800 r/min reference speed is the thermal balance under catalogue load; the 1,100 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." } ], "cross_ref": [ { "equiv_sku": "51334", "equiv_brand": "NTN", "level": "partial", "note": "Same 170×280×87 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51334", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51334-M", "51334 M" ], "locale_variants": {} }, { "sku": "51136-M", "brand": "SKF", "manufacturer_designation": "51136 M", "series": "51100-series", "type": "thrust_ball", "d_mm": 180, "D_mm": 225, "B_mm": 34, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 135, "static_load_kN": 570, "fatigue_load_limit_kN": 15, "reference_speed_rpm": 1500, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 3500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51136 M is an ISO 104 single-direction thrust ball bearing, 180 mm bore and 225 mm OD on a flat housing seat, standing 34 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 36: bore 180 mm (code 36 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. Envelope 180×225×34 mm (7.087×8.858×1.339 in), 22.5 mm radial section, C 135 kN, C0 570 kN, Pu 15 kN. reference speed 1,500 r/min (thermal) and limiting speed 2,200 r/min (mechanical), catalogue mass 3500 g. Speed-ratio note for this exact unit: the reference speed is 1,500 r/min against a 2,200 r/min limiting speed, a reference-to-limit ratio of 0.68. Load balance: C0 570 kN against C 135 kN gives a 4.22 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 15 kN enters the adjusted-life check. Minimum-load arithmetic: with dm ≈ 202.5 mm and factor A 1.7, Fam ≈ A·(n·dm/1000)² at the 1,500 r/min reference speed is about 156.8 kN for 51136 M; below that preload the balls skid and smear the tracks. Speed band width for this size is 700 r/min between reference and limiting (1.47× ratio); lubrication, preload and heat removal decide where inside that band 51136 M can actually run. Stack/annulus proportions: the 34 mm axial stack over the 14,314 mm² washer annulus gives 2.38 mm of height per annular square millimetre ×10⁻³, and at 3500 g the bearing holds about 162.9 kN of C0 per kilogram. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 3500 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 180 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "large press rams and screwdown mechanisms", "marine gearbox thrust positions", "very heavy crane and ladle hooks" ], "failure_modes": [ "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "cage damage from mounting force applied through the balls instead of the washer face", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51136 against two-way load lifts the loose washer off its raceway.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 135/570 kN and the available 225 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 34 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 135 kN track before first rotation.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51136 M as the single flat brass execution; other order numbers of the 51136 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51136-M?", "a": "The catalogue envelope is 180×225×34 mm, mass 3500 g; ratings C 135 kN / C0 570 kN / Pu 15 kN, reference speed 1,500 r/min (thermal) and limiting speed 2,200 r/min (mechanical)." }, { "q": "What does the designation 51136 M mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 36: bore 180 mm (code 36 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can 51136-M carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 180 mm shaft must go to a separate radial bearing; mixed loading through 51136 M edge-loads the balls and destroys the washers." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." } ], "cross_ref": [ { "equiv_sku": "51136", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "51136", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51136-M", "51136 M" ], "locale_variants": {} }, { "sku": "51236-M", "brand": "SKF", "manufacturer_designation": "51236 M", "series": "51200-series", "type": "thrust_ball", "d_mm": 180, "D_mm": 250, "B_mm": 56, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 302, "static_load_kN": 1120, "fatigue_load_limit_kN": 28.5, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1600, "max_rpm": 1600, "weight_g": 8600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51200 series order number 51236 M is a SKF single-direction thrust ball bearing for a 180 mm seat, built to ISO 104, with a flat housing seating surface, 180×250×56 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 36 decodes to 180 mm (code 36 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 180×250×56 mm (7.087×9.843×2.205 in), 35.0 mm radial section, C 302 kN, C0 1120 kN, Pu 28.5 kN. reference speed 1,200 r/min (thermal) and limiting speed 1,600 r/min (mechanical), catalogue mass 8600 g. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 6.1 at the 1,600 r/min limiting speed raises the required axial preload to about 721.8 kN; the reference-speed value 406.0 kN is the thermal design point. Envelope economics: the 56 mm axial height over a 35.0 mm radial section yields 5.4 kN of dynamic capacity per height millimetre, and the bearing weighs 8600 g for 302 kN C — about 28 g per rated kN. Speed band width for this size is 400 r/min between reference and limiting (1.33× ratio); lubrication, preload and heat removal decide where inside that band 51236 M can actually run. Capacity density: 302 kN C from 8.600 kg of bearing steel gives about 35.1 kN per kilogram; static density is correspondingly 130.2 kN/kg at C0 1120 kN. Track-circle loading: per millimetre of mean track circumference the 302 kN dynamic rating corresponds to roughly 0.45 kN/mm of π·dm track, a useful comparison against the other dimension series of the 180 mm bore. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 8600 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 180 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "very heavy crane and ladle hooks", "offshore and dock winch drums", "heavy converter and ladle-tilt pivots" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 56 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 302 kN track before first rotation.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 302/1120 kN and the available 250 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51236 against two-way load lifts the loose washer off its raceway.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51236 M as the single flat brass execution; other order numbers of the 51236 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51236-M?", "a": "Boundary dimensions to ISO 104: bore 180 mm, OD 250 mm, height 56 mm; weight 8600 g. Load figures from SKF 17000: dynamic 302 kN, static 1120 kN, fatigue limit 28.5 kN; reference speed 1,200 r/min (thermal) and limiting speed 1,600 r/min (mechanical)." }, { "q": "What does the designation 51236 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 36 decodes to 180 mm (code 36 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number is a different, M-cage product) uses the standard stamped sheet-steel pressed cage." }, { "q": "Can 51236-M carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 180 mm shaft must go to a separate radial bearing; mixed loading through 51236 M edge-loads the balls and destroys the washers." } ], "cross_ref": [ { "equiv_sku": "51236", "equiv_brand": "NTN", "level": "partial", "note": "Same 180×250×56 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51236", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51236-M", "51236 M" ], "locale_variants": {} }, { "sku": "51336-M", "brand": "SKF", "manufacturer_designation": "51336 M", "series": "51300-series", "type": "thrust_ball", "d_mm": 180, "D_mm": 300, "B_mm": 95, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 520, "static_load_kN": 2000, "fatigue_load_limit_kN": 47.5, "reference_speed_rpm": 750, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 28500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51336 M is an ISO 104 single-direction thrust ball bearing, 180 mm bore and 300 mm OD on a flat housing seat, standing 95 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 36: bore 180 mm (code 36 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. Envelope 180×300×95 mm (7.087×11.811×3.74 in), 60.0 mm radial section, C 520 kN, C0 2000 kN, Pu 47.5 kN. reference speed 750 r/min (thermal) and limiting speed 1,100 r/min (mechanical), catalogue mass 28500 g. Rating split for documentation: dynamic 520 kN (L10 life), static 2000 kN (safety factor s0), fatigue limit 47.5 kN (adjusted life) — three different uses of three different numbers for 51336 M, none interchangeable with another. Light-load floor: Pu = 47.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51336 M; the number is 9 % of the 520 kN dynamic rating. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51336 M covers about 45,239 mm², distributing C0 2000 kN over a mean track circle of π·dm ≈ 754 mm. Speed band width for this size is 350 r/min between reference and limiting (1.47× ratio); lubrication, preload and heat removal decide where inside that band 51336 M can actually run. Sizing arithmetic on the 180 mm bore: 520 kN C over the 60.0 mm radial section gives 8.7 kN per section millimetre, and the 95 mm stack height is 1.58× that section — proportions typical of a 51300 thrust section. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51336 M adds a small amount of mass and cage strength without changing the 180×300×95 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,100 r/min ceiling.", "applications": [ "large press rams and screwdown mechanisms", "heavy converter and ladle-tilt pivots", "very heavy crane and ladle hooks" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "washer face scoring from swarf trapped between the loose housing washer and its register", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "The 51336 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 180 mm shaft has to be carried by a radial bearing mounted alongside it.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 95 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51336 against two-way load lifts the loose washer off its raceway.", "The 520/2000 kN figures belong to 51336 M specifically (the single flat brass execution of 51336); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51336-M?", "a": "The catalogue envelope is 180×300×95 mm, mass 28500 g; ratings C 520 kN / C0 2000 kN / Pu 47.5 kN, reference speed 750 r/min (thermal) and limiting speed 1,100 r/min (mechanical)." }, { "q": "What does the designation 51336 M mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 36: bore 180 mm (code 36 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51336-M lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 1,100 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 180 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51336", "equiv_brand": "NTN", "level": "partial", "note": "Same 180×300×95 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51336", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51336-M", "51336 M" ], "locale_variants": {} }, { "sku": "51138-M", "brand": "SKF", "manufacturer_designation": "51138 M", "series": "51100-series", "type": "thrust_ball", "d_mm": 190, "D_mm": 240, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 172, "static_load_kN": 710, "fatigue_load_limit_kN": 18, "reference_speed_rpm": 1400, "limiting_speed_rpm": 2000, "max_rpm": 2000, "weight_g": 4050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51138 M is a SKF single-direction thrust ball bearing for a 190 mm seat, built to ISO 104, with a flat housing seating surface, 190×240×37 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 38 decodes to 190 mm (code 38 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 190×240×37 mm (7.48×9.449×1.457 in), 25.0 mm radial section, C 172 kN, C0 710 kN, Pu 18 kN. reference speed 1,400 r/min (thermal) and limiting speed 2,000 r/min (mechanical), catalogue mass 4050 g. Mass and section check: 4050 g inside the 190×240×37 mm outline leaves a 25.0 mm radial section, and the 710 kN static rating is 4.13× the dynamic rating — plan static safety and minimum preload against those figures. Pitch-diameter arithmetic: dm = (190+240)/2 = 215.0 mm; at the 2,000 r/min limiting speed that corresponds to roughly 430k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Selection figures for 51138 M: the C0/C ratio is 4.13, Pu 18 kN is about 10 % of C, and the catalogue mass works out to roughly 21 g per millimetre of bore; the printed minimum-load factor is A 2.6. Load balance: C0 710 kN against C 172 kN gives a 4.13 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 18 kN enters the adjusted-life check. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 2.6 at the 2,000 r/min limiting speed raises the required axial preload to about 480.7 kN; the reference-speed value 235.6 kN is the thermal design point. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51138 M adds a small amount of mass and cage strength without changing the 190×240×37 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 2,000 r/min ceiling.", "applications": [ "marine gearbox thrust positions", "very heavy crane and ladle hooks", "offshore and dock winch drums" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "false brinelling of the stationary tracks while the machine stands under vibration", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 2.6; for 51138 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "When the housing seat cannot be machined square to the 190 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 172/710 kN and the available 240 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The 172/710 kN figures belong to 51138 M specifically (the single flat brass execution of 51138); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51138-M?", "a": "Boundary dimensions to ISO 104: bore 190 mm, OD 240 mm, height 37 mm; weight 4050 g. Load figures from SKF 17000: dynamic 172 kN, static 710 kN, fatigue limit 18 kN; reference speed 1,400 r/min (thermal) and limiting speed 2,000 r/min (mechanical)." }, { "q": "What does the designation 51138 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 38 decodes to 190 mm (code 38 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51138-M lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 2,000 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 190 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51138", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "51138", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51138-M", "51138 M" ], "locale_variants": {} }, { "sku": "51238-M", "brand": "SKF", "manufacturer_designation": "51238 M", "series": "51200-series", "type": "thrust_ball", "d_mm": 190, "D_mm": 270, "B_mm": 62, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 332, "static_load_kN": 1270, "fatigue_load_limit_kN": 31, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1600, "max_rpm": 1600, "weight_g": 12000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51238 M is SKF's 190 mm-bore single-direction thrust ball bearing in the 51200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 190×270×62 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 38 encode the bore as 190 mm (code 38 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 190×270×62 mm (7.48×10.63×2.441 in), 40.0 mm radial section, C 332 kN, C0 1270 kN, Pu 31 kN. reference speed 1,100 r/min (thermal) and limiting speed 1,600 r/min (mechanical), catalogue mass 12000 g. Stack/annulus proportions: the 62 mm axial stack over the 28,903 mm² washer annulus gives 2.15 mm of height per annular square millimetre ×10⁻³, and at 12000 g the bearing holds about 105.8 kN of C0 per kilogram. Track-circle loading: per millimetre of mean track circumference the 332 kN dynamic rating corresponds to roughly 0.46 kN/mm of π·dm track, a useful comparison against the other dimension series of the 190 mm bore. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 8.4 at the 1,600 r/min limiting speed raises the required axial preload to about 1137.6 kN; the reference-speed value 537.7 kN is the thermal design point. Light-load floor: Pu = 31 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51238 M; the number is 9 % of the 332 kN dynamic rating. At the printed limiting speed of 1,600 r/min the mean pitch diameter dm ≈ 230.0 mm implies a dn value around 368k mm·r/min; the 1,100 r/min reference speed is the thermal-planning value under catalogue load. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 12000 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 190 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "large press rams and screwdown mechanisms", "very heavy crane and ladle hooks", "heavy converter and ladle-tilt pivots" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 332/1270 kN and the available 270 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51238 against two-way load lifts the loose washer off its raceway.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 332 kN track before first rotation.", "Ordering discipline for 51238: the catalogue page quotes 51238 M and its 332/1270 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51238-M?", "a": "51238 M measures 190 mm bore × 270 mm OD × 62 mm bearing height (7.48 × 10.63 × 2.441 in), mass about 12000 g. SKF 17000 ratings: C 332 kN, C0 1270 kN, Pu 31 kN, reference speed 1,100 r/min (thermal) and limiting speed 1,600 r/min (mechanical)." }, { "q": "What does the designation 51238 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 38 encode the bore as 190 mm (code 38 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51238-M?", "a": "The 1,100 r/min reference speed is the thermal balance under catalogue load; the 1,600 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51238-M need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 8.4 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51238", "equiv_brand": "NTN", "level": "partial", "note": "Same 190×270×62 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51238", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51238-M", "51238 M" ], "locale_variants": {} }, { "sku": "51338-M", "brand": "SKF", "manufacturer_designation": "51338 M", "series": "51300-series", "type": "thrust_ball", "d_mm": 190, "D_mm": 320, "B_mm": 105, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 559, "static_load_kN": 2200, "fatigue_load_limit_kN": 51, "reference_speed_rpm": 700, "limiting_speed_rpm": 950, "max_rpm": 950, "weight_g": 36500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51300 series order number 51338 M is a SKF single-direction thrust ball bearing for a 190 mm seat, built to ISO 104, with a flat housing seating surface, 190×320×105 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 38 decodes to 190 mm (code 38 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 190×320×105 mm (7.48×12.598×4.134 in), 65.0 mm radial section, C 559 kN, C0 2200 kN, Pu 51 kN. reference speed 700 r/min (thermal) and limiting speed 950 r/min (mechanical), catalogue mass 36500 g. Track-circle loading: per millimetre of mean track circumference the 559 kN dynamic rating corresponds to roughly 0.70 kN/mm of π·dm track, a useful comparison against the other dimension series of the 190 mm bore. Light-load floor: Pu = 51 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51338 M; the number is 9 % of the 559 kN dynamic rating. Stack/annulus proportions: the 105 mm axial stack over the 52,072 mm² washer annulus gives 2.02 mm of height per annular square millimetre ×10⁻³, and at 36500 g the bearing holds about 60.3 kN of C0 per kilogram. Mass and section check: 36500 g inside the 190×320×105 mm outline leaves a 65.0 mm radial section, and the 2200 kN static rating is 3.94× the dynamic rating — plan static safety and minimum preload against those figures. Capacity density: 559 kN C from 36.500 kg of bearing steel gives about 15.3 kN per kilogram; static density is correspondingly 60.3 kN/kg at C0 2200 kN. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 36500 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 190 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "large press rams and screwdown mechanisms", "very heavy crane and ladle hooks", "marine gearbox thrust positions" ], "failure_modes": [ "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "false brinelling of the stationary tracks while the machine stands under vibration", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 30; for 51338 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The 51338 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 190 mm shaft has to be carried by a radial bearing mounted alongside it.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 559/2200 kN and the available 320 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 190 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Ordering discipline for 51338: the catalogue page quotes 51338 M and its 559/2200 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51338-M?", "a": "Boundary dimensions to ISO 104: bore 190 mm, OD 320 mm, height 105 mm; weight 36500 g. Load figures from SKF 17000: dynamic 559 kN, static 2200 kN, fatigue limit 51 kN; reference speed 700 r/min (thermal) and limiting speed 950 r/min (mechanical)." }, { "q": "What does the designation 51338 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 38 decodes to 190 mm (code 38 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can 51338-M carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 190 mm shaft must go to a separate radial bearing; mixed loading through 51338 M edge-loads the balls and destroys the washers." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." } ], "cross_ref": [ { "equiv_sku": "51338", "equiv_brand": "NTN", "level": "partial", "note": "Same 190×320×105 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51338", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51338-M", "51338 M" ], "locale_variants": {} }, { "sku": "51140-M", "brand": "SKF", "manufacturer_designation": "51140 M", "series": "51100-series", "type": "thrust_ball", "d_mm": 200, "D_mm": 250, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 168, "static_load_kN": 710, "fatigue_load_limit_kN": 17.6, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1900, "max_rpm": 1900, "weight_g": 4250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51140 M is an ISO 104 single-direction thrust ball bearing, 200 mm bore and 250 mm OD on a flat housing seat, standing 37 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 40: bore 200 mm (code 40 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. Envelope 200×250×37 mm (7.874×9.843×1.457 in), 25.0 mm radial section, C 168 kN, C0 710 kN, Pu 17.6 kN. reference speed 1,400 r/min (thermal) and limiting speed 1,900 r/min (mechanical), catalogue mass 4250 g. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 2.6 at the 1,900 r/min limiting speed raises the required axial preload to about 475.2 kN; the reference-speed value 258.0 kN is the thermal design point. Static-first selection data: 710 kN C0 spread across the 37 mm stack gives 19.2 kN of static rating per height millimetre, and the 4250 g mass/C0 ratio is about 6 g per static kN — crane-hook and screw positions are normally sized on these two figures. Sizing arithmetic on the 200 mm bore: 168 kN C over the 25.0 mm radial section gives 6.7 kN per section millimetre, and the 37 mm stack height is 1.48× that section — proportions typical of a 51100 thrust section. Rating split for documentation: dynamic 168 kN (L10 life), static 710 kN (safety factor s0), fatigue limit 17.6 kN (adjusted life) — three different uses of three different numbers for 51140 M, none interchangeable with another. Selection figures for 51140 M: the C0/C ratio is 4.23, Pu 17.6 kN is about 10 % of C, and the catalogue mass works out to roughly 21 g per millimetre of bore; the printed minimum-load factor is A 2.6. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 4250 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 200 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "heavy converter and ladle-tilt pivots", "very heavy crane and ladle hooks", "marine gearbox thrust positions" ], "failure_modes": [ "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "track rust staining from condensate during long idle periods in humid plant air" ], "pitfalls": [ "When the housing seat cannot be machined square to the 200 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 168/710 kN and the available 250 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 37 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51140 against two-way load lifts the loose washer off its raceway.", "Ordering discipline for 51140: the catalogue page quotes 51140 M and its 168/710 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51140-M?", "a": "The catalogue envelope is 200×250×37 mm, mass 4250 g; ratings C 168 kN / C0 710 kN / Pu 17.6 kN, reference speed 1,400 r/min (thermal) and limiting speed 1,900 r/min (mechanical)." }, { "q": "What does the designation 51140 M mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 40: bore 200 mm (code 40 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 200 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51140 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51140", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "51140", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51140-M", "51140 M" ], "locale_variants": {} }, { "sku": "51240-M", "brand": "SKF", "manufacturer_designation": "51240 M", "series": "51200-series", "type": "thrust_ball", "d_mm": 200, "D_mm": 280, "B_mm": 62, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 338, "static_load_kN": 1320, "fatigue_load_limit_kN": 31.5, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1500, "max_rpm": 1500, "weight_g": 12000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51200 series order number 51240 M is a SKF single-direction thrust ball bearing for a 200 mm seat, built to ISO 104, with a flat housing seating surface, 200×280×62 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 40 decodes to 200 mm (code 40 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 200×280×62 mm (7.874×11.024×2.441 in), 40.0 mm radial section, C 338 kN, C0 1320 kN, Pu 31.5 kN. reference speed 1,100 r/min (thermal) and limiting speed 1,500 r/min (mechanical), catalogue mass 12000 g. Rating split for documentation: dynamic 338 kN (L10 life), static 1320 kN (safety factor s0), fatigue limit 31.5 kN (adjusted life) — three different uses of three different numbers for 51240 M, none interchangeable with another. Sizing arithmetic on the 200 mm bore: 338 kN C over the 40.0 mm radial section gives 8.4 kN per section millimetre, and the 62 mm stack height is 1.55× that section — proportions typical of a 51200 thrust section. Bore-to-OD planning: OD 280 over bore 200 is a 1.40× step for this size, and the 62 mm height gives a bore/height ratio of 3.23; use these ratios when the housing recess around the 200 mm shaft is the first constraint. Speed band width for this size is 400 r/min between reference and limiting (1.36× ratio); lubrication, preload and heat removal decide where inside that band 51240 M can actually run. Envelope economics: the 62 mm axial height over a 40.0 mm radial section yields 5.5 kN of dynamic capacity per height millimetre, and the bearing weighs 12000 g for 338 kN C — about 36 g per rated kN. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51240 M adds a small amount of mass and cage strength without changing the 200×280×62 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,500 r/min ceiling.", "applications": [ "heavy converter and ladle-tilt pivots", "large press rams and screwdown mechanisms", "marine gearbox thrust positions" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "cage damage from mounting force applied through the balls instead of the washer face", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51240 against two-way load lifts the loose washer off its raceway.", "When the housing seat cannot be machined square to the 200 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 62 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The 338/1320 kN figures belong to 51240 M specifically (the single flat brass execution of 51240); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51240-M?", "a": "Boundary dimensions to ISO 104: bore 200 mm, OD 280 mm, height 62 mm; weight 12000 g. Load figures from SKF 17000: dynamic 338 kN, static 1320 kN, fatigue limit 31.5 kN; reference speed 1,100 r/min (thermal) and limiting speed 1,500 r/min (mechanical)." }, { "q": "What does the designation 51240 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 40 decodes to 200 mm (code 40 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can 51240-M carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 200 mm shaft must go to a separate radial bearing; mixed loading through 51240 M edge-loads the balls and destroys the washers." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." } ], "cross_ref": [ { "equiv_sku": "51240", "equiv_brand": "NTN", "level": "partial", "note": "Same 200×280×62 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51240", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51240-M", "51240 M" ], "locale_variants": {} }, { "sku": "51340-M", "brand": "SKF", "manufacturer_designation": "51340 M", "series": "51300-series", "type": "thrust_ball", "d_mm": 200, "D_mm": 340, "B_mm": 110, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 624, "static_load_kN": 2600, "fatigue_load_limit_kN": 58.5, "reference_speed_rpm": 630, "limiting_speed_rpm": 900, "max_rpm": 900, "weight_g": 44500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51340 M is an ISO 104 single-direction thrust ball bearing, 200 mm bore and 340 mm OD on a flat housing seat, standing 110 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 40: bore 200 mm (code 40 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. Envelope 200×340×110 mm (7.874×13.386×4.331 in), 70.0 mm radial section, C 624 kN, C0 2600 kN, Pu 58.5 kN. reference speed 630 r/min (thermal) and limiting speed 900 r/min (mechanical), catalogue mass 44500 g. Stack/annulus proportions: the 110 mm axial stack over the 59,376 mm² washer annulus gives 1.85 mm of height per annular square millimetre ×10⁻³, and at 44500 g the bearing holds about 58.4 kN of C0 per kilogram. Envelope economics: the 110 mm axial height over a 70.0 mm radial section yields 5.7 kN of dynamic capacity per height millimetre, and the bearing weighs 44500 g for 624 kN C — about 71 g per rated kN. Pitch-diameter arithmetic: dm = (200+340)/2 = 270.0 mm; at the 900 r/min limiting speed that corresponds to roughly 243k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Speed band width for this size is 270 r/min between reference and limiting (1.43× ratio); lubrication, preload and heat removal decide where inside that band 51340 M can actually run. Speed-ratio note for this exact unit: the reference speed is 630 r/min against a 900 r/min limiting speed, a reference-to-limit ratio of 0.70. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 44500 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 200 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "marine gearbox thrust positions", "large press rams and screwdown mechanisms", "heavy converter and ladle-tilt pivots" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 624/2600 kN and the available 340 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 200 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51340 against two-way load lifts the loose washer off its raceway.", "When the housing seat cannot be machined square to the 200 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51300 bearing.", "Ordering discipline for 51340: the catalogue page quotes 51340 M and its 624/2600 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51340-M?", "a": "The catalogue envelope is 200×340×110 mm, mass 44500 g; ratings C 624 kN / C0 2600 kN / Pu 58.5 kN, reference speed 630 r/min (thermal) and limiting speed 900 r/min (mechanical)." }, { "q": "What does the designation 51340 M mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 40: bore 200 mm (code 40 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51340-M?", "a": "The 630 r/min reference speed is the thermal balance under catalogue load; the 900 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51340-M need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 35 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51340", "equiv_brand": "NTN", "level": "partial", "note": "Same 200×340×110 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51340", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51340-M", "51340 M" ], "locale_variants": {} }, { "sku": "51144-M", "brand": "SKF", "manufacturer_designation": "51144 M", "series": "51100-series", "type": "thrust_ball", "d_mm": 220, "D_mm": 270, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 178, "static_load_kN": 800, "fatigue_load_limit_kN": 19, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1900, "max_rpm": 1900, "weight_g": 4600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51144 M is SKF's 220 mm-bore single-direction thrust ball bearing in the 51100 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 220×270×37 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 44 encode the bore as 220 mm (code 44 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 220×270×37 mm (8.661×10.63×1.457 in), 25.0 mm radial section, C 178 kN, C0 800 kN, Pu 19 kN. reference speed 1,300 r/min (thermal) and limiting speed 1,900 r/min (mechanical), catalogue mass 4600 g. Mass and section check: 4600 g inside the 220×270×37 mm outline leaves a 25.0 mm radial section, and the 800 kN static rating is 4.49× the dynamic rating — plan static safety and minimum preload against those figures. Static-first selection data: 800 kN C0 spread across the 37 mm stack gives 21.6 kN of static rating per height millimetre, and the 4600 g mass/C0 ratio is about 6 g per static kN — crane-hook and screw positions are normally sized on these two figures. Capacity density: 178 kN C from 4.600 kg of bearing steel gives about 38.7 kN per kilogram; static density is correspondingly 173.9 kN/kg at C0 800 kN. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51144 M covers about 19,242 mm², distributing C0 800 kN over a mean track circle of π·dm ≈ 770 mm. Sizing arithmetic on the 220 mm bore: 178 kN C over the 25.0 mm radial section gives 7.1 kN per section millimetre, and the 37 mm stack height is 1.48× that section — proportions typical of a 51100 thrust section. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 4600 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 220 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "very heavy crane and ladle hooks", "marine gearbox thrust positions", "offshore and dock winch drums" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "false brinelling of the stationary tracks while the machine stands under vibration" ], "pitfalls": [ "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 220 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 3.3; for 51144 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "When the housing seat cannot be machined square to the 220 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 37 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The 178/800 kN figures belong to 51144 M specifically (the single flat brass execution of 51144); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51144-M?", "a": "51144 M measures 220 mm bore × 270 mm OD × 37 mm bearing height (8.661 × 10.63 × 1.457 in), mass about 4600 g. SKF 17000 ratings: C 178 kN, C0 800 kN, Pu 19 kN, reference speed 1,300 r/min (thermal) and limiting speed 1,900 r/min (mechanical)." }, { "q": "What does the designation 51144 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 44 encode the bore as 220 mm (code 44 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number is a different, M-cage product) uses the standard stamped sheet-steel pressed cage." }, { "q": "Can 51144-M carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 220 mm shaft must go to a separate radial bearing; mixed loading through 51144 M edge-loads the balls and destroys the washers." } ], "cross_ref": [ { "equiv_sku": "51144", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "51144", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51144-M", "51144 M" ], "locale_variants": {} }, { "sku": "51244-M", "brand": "SKF", "manufacturer_designation": "51244 M", "series": "51200-series", "type": "thrust_ball", "d_mm": 220, "D_mm": 300, "B_mm": 63, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 358, "static_load_kN": 1460, "fatigue_load_limit_kN": 33.5, "reference_speed_rpm": 950, "limiting_speed_rpm": 1300, "max_rpm": 1300, "weight_g": 13000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51244 M is SKF's 220 mm-bore single-direction thrust ball bearing in the 51200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 220×300×63 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 44 encode the bore as 220 mm (code 44 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 220×300×63 mm (8.661×11.811×2.48 in), 40.0 mm radial section, C 358 kN, C0 1460 kN, Pu 33.5 kN. reference speed 950 r/min (thermal) and limiting speed 1,300 r/min (mechanical), catalogue mass 13000 g. Load balance: C0 1460 kN against C 358 kN gives a 4.08 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 33.5 kN enters the adjusted-life check. Speed band width for this size is 350 r/min between reference and limiting (1.37× ratio); lubrication, preload and heat removal decide where inside that band 51244 M can actually run. Track-circle loading: per millimetre of mean track circumference the 358 kN dynamic rating corresponds to roughly 0.44 kN/mm of π·dm track, a useful comparison against the other dimension series of the 220 mm bore. Stack/annulus proportions: the 63 mm axial stack over the 32,673 mm² washer annulus gives 1.93 mm of height per annular square millimetre ×10⁻³, and at 13000 g the bearing holds about 112.3 kN of C0 per kilogram. Mass and section check: 13000 g inside the 220×300×63 mm outline leaves a 40.0 mm radial section, and the 1460 kN static rating is 4.08× the dynamic rating — plan static safety and minimum preload against those figures. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51244 M adds a small amount of mass and cage strength without changing the 220×300×63 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,300 r/min ceiling.", "applications": [ "large press rams and screwdown mechanisms", "very heavy crane and ladle hooks", "offshore and dock winch drums" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "false brinelling of the stationary tracks while the machine stands under vibration", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 220 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 358 kN track before first rotation.", "When the housing seat cannot be machined square to the 220 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 63 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The 358/1460 kN figures belong to 51244 M specifically (the single flat brass execution of 51244); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51244-M?", "a": "51244 M measures 220 mm bore × 300 mm OD × 63 mm bearing height (8.661 × 11.811 × 2.48 in), mass about 13000 g. SKF 17000 ratings: C 358 kN, C0 1460 kN, Pu 33.5 kN, reference speed 950 r/min (thermal) and limiting speed 1,300 r/min (mechanical)." }, { "q": "What does the designation 51244 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 44 encode the bore as 220 mm (code 44 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can a single 51244 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." }, { "q": "What do the two published speeds mean for 51244-M?", "a": "The 950 r/min reference speed is the thermal balance under catalogue load; the 1,300 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." } ], "cross_ref": [ { "equiv_sku": "51244", "equiv_brand": "NTN", "level": "partial", "note": "Same 220×300×63 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51244", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51244-M", "51244 M" ], "locale_variants": {} }, { "sku": "51148-M", "brand": "SKF", "manufacturer_designation": "51148 M", "series": "51100-series", "type": "thrust_ball", "d_mm": 240, "D_mm": 300, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 234, "static_load_kN": 1040, "fatigue_load_limit_kN": 23.6, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1600, "max_rpm": 1600, "weight_g": 7550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51148 M is SKF's 240 mm-bore single-direction thrust ball bearing in the 51100 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 240×300×45 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 48 encode the bore as 240 mm (code 48 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 240×300×45 mm (9.449×11.811×1.772 in), 30.0 mm radial section, C 234 kN, C0 1040 kN, Pu 23.6 kN. reference speed 1,100 r/min (thermal) and limiting speed 1,600 r/min (mechanical), catalogue mass 7550 g. Imperial cross-check for procurement drawings: 9.449 in bore, 11.811 in OD, 1.772 in height, and the 7550 g catalogue mass converts to 7.550 kg (266.3 oz). Washer-annulus check: the π/4·(D²−d²) contact annulus of 51148 M covers about 25,447 mm², distributing C0 1040 kN over a mean track circle of π·dm ≈ 848 mm. Speed planning separates the two ceilings mechanically: the pressed brass cage and balls tolerate 1,600 r/min while thermal balance under catalogue load sets the 1,100 r/min reference; at dm ≈ 270.0 mm the corresponding dn is approximately 432k mm·r/min. Speed band width for this size is 500 r/min between reference and limiting (1.45× ratio); lubrication, preload and heat removal decide where inside that band 51148 M can actually run. Static-first selection data: 1040 kN C0 spread across the 45 mm stack gives 23.1 kN of static rating per height millimetre, and the 7550 g mass/C0 ratio is about 7 g per static kN — crane-hook and screw positions are normally sized on these two figures. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51148 M adds a small amount of mass and cage strength without changing the 240×300×45 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,600 r/min ceiling.", "applications": [ "heavy converter and ladle-tilt pivots", "marine gearbox thrust positions", "large press rams and screwdown mechanisms" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 5.6; for 51148 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The 51148 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 240 mm shaft has to be carried by a radial bearing mounted alongside it.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 240 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Ordering discipline for 51148: the catalogue page quotes 51148 M and its 234/1040 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51148-M?", "a": "51148 M measures 240 mm bore × 300 mm OD × 45 mm bearing height (9.449 × 11.811 × 1.772 in), mass about 7550 g. SKF 17000 ratings: C 234 kN, C0 1040 kN, Pu 23.6 kN, reference speed 1,100 r/min (thermal) and limiting speed 1,600 r/min (mechanical)." }, { "q": "What does the designation 51148 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 48 encode the bore as 240 mm (code 48 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 240 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51148 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51148", "equiv_brand": "NTN", "level": "partial", "note": "Same 240×300×45 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51148", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51148-M", "51148 M" ], "locale_variants": {} }, { "sku": "51248-M", "brand": "SKF", "manufacturer_designation": "51248 M", "series": "51200-series", "type": "thrust_ball", "d_mm": 240, "D_mm": 340, "B_mm": 78, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 449, "static_load_kN": 1960, "fatigue_load_limit_kN": 42.5, "reference_speed_rpm": 800, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 23000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51248 M is an ISO 104 single-direction thrust ball bearing, 240 mm bore and 340 mm OD on a flat housing seat, standing 78 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 48: bore 240 mm (code 48 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. Envelope 240×340×78 mm (9.449×13.386×3.071 in), 50.0 mm radial section, C 449 kN, C0 1960 kN, Pu 42.5 kN. reference speed 800 r/min (thermal) and limiting speed 1,100 r/min (mechanical), catalogue mass 23000 g. Stack/annulus proportions: the 78 mm axial stack over the 45,553 mm² washer annulus gives 1.71 mm of height per annular square millimetre ×10⁻³, and at 23000 g the bearing holds about 85.2 kN of C0 per kilogram. Imperial cross-check for procurement drawings: 9.449 in bore, 13.386 in OD, 3.071 in height, and the 23000 g catalogue mass converts to 23.000 kg (811.3 oz). Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 21 at the 1,100 r/min limiting speed raises the required axial preload to about 2137.0 kN; the reference-speed value 1130.3 kN is the thermal design point. Speed band width for this size is 300 r/min between reference and limiting (1.38× ratio); lubrication, preload and heat removal decide where inside that band 51248 M can actually run. Envelope economics: the 78 mm axial height over a 50.0 mm radial section yields 5.8 kN of dynamic capacity per height millimetre, and the bearing weighs 23000 g for 449 kN C — about 51 g per rated kN. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51248 M adds a small amount of mass and cage strength without changing the 240×340×78 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,100 r/min ceiling.", "applications": [ "very heavy crane and ladle hooks", "large press rams and screwdown mechanisms", "marine gearbox thrust positions" ], "failure_modes": [ "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "cage damage from mounting force applied through the balls instead of the washer face", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 78 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 449 kN track before first rotation.", "The 51248 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 240 mm shaft has to be carried by a radial bearing mounted alongside it.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51248 against two-way load lifts the loose washer off its raceway.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51248 M as the single flat brass execution; other order numbers of the 51248 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51248-M?", "a": "The catalogue envelope is 240×340×78 mm, mass 23000 g; ratings C 449 kN / C0 1960 kN / Pu 42.5 kN, reference speed 800 r/min (thermal) and limiting speed 1,100 r/min (mechanical)." }, { "q": "What does the designation 51248 M mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 48: bore 240 mm (code 48 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Can 51248-M carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 240 mm shaft must go to a separate radial bearing; mixed loading through 51248 M edge-loads the balls and destroys the washers." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." } ], "cross_ref": [ { "equiv_sku": "51248", "equiv_brand": "NTN", "level": "partial", "note": "Same 240×340×78 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51248", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51248-M", "51248 M" ], "locale_variants": {} }, { "sku": "51152-M", "brand": "SKF", "manufacturer_designation": "51152 M", "series": "51100-series", "type": "thrust_ball", "d_mm": 260, "D_mm": 320, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 238, "static_load_kN": 1100, "fatigue_load_limit_kN": 24, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1500, "max_rpm": 1500, "weight_g": 8100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51152 M is an ISO 104 single-direction thrust ball bearing, 260 mm bore and 320 mm OD on a flat housing seat, standing 45 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 52: bore 260 mm (code 52 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. Envelope 260×320×45 mm (10.236×12.598×1.772 in), 30.0 mm radial section, C 238 kN, C0 1100 kN, Pu 24 kN. reference speed 1,100 r/min (thermal) and limiting speed 1,500 r/min (mechanical), catalogue mass 8100 g. At the printed limiting speed of 1,500 r/min the mean pitch diameter dm ≈ 290.0 mm implies a dn value around 435k mm·r/min; the 1,100 r/min reference speed is the thermal-planning value under catalogue load. Rating split for documentation: dynamic 238 kN (L10 life), static 1100 kN (safety factor s0), fatigue limit 24 kN (adjusted life) — three different uses of three different numbers for 51152 M, none interchangeable with another. Sizing arithmetic on the 260 mm bore: 238 kN C over the 30.0 mm radial section gives 7.9 kN per section millimetre, and the 45 mm stack height is 1.50× that section — proportions typical of a 51100 thrust section. Load balance: C0 1100 kN against C 238 kN gives a 4.62 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 24 kN enters the adjusted-life check. Selection figures for 51152 M: the C0/C ratio is 4.62, Pu 24 kN is about 10 % of C, and the catalogue mass works out to roughly 31 g per millimetre of bore; the printed minimum-load factor is A 6.3. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 8100 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 260 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "very heavy crane and ladle hooks", "marine gearbox thrust positions", "heavy converter and ladle-tilt pivots" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "The 51152 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 260 mm shaft has to be carried by a radial bearing mounted alongside it.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 6.3; for 51152 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 260 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 238 kN track before first rotation.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51152 M as the single flat brass execution; other order numbers of the 51152 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51152-M?", "a": "The catalogue envelope is 260×320×45 mm, mass 8100 g; ratings C 238 kN / C0 1100 kN / Pu 24 kN, reference speed 1,100 r/min (thermal) and limiting speed 1,500 r/min (mechanical)." }, { "q": "What does the designation 51152 M mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 52: bore 260 mm (code 52 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51152-M lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 1,500 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 260 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51152", "equiv_brand": "NTN", "level": "partial", "note": "Same 260×320×45 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51152", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51152-M", "51152 M" ], "locale_variants": {} }, { "sku": "51252-M", "brand": "SKF", "manufacturer_designation": "51252 M", "series": "51200-series", "type": "thrust_ball", "d_mm": 260, "D_mm": 360, "B_mm": 79, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 488, "static_load_kN": 2240, "fatigue_load_limit_kN": 46.5, "reference_speed_rpm": 750, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 25000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51252 M is an ISO 104 single-direction thrust ball bearing, 260 mm bore and 360 mm OD on a flat housing seat, standing 79 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 52: bore 260 mm (code 52 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. Envelope 260×360×79 mm (10.236×14.173×3.11 in), 50.0 mm radial section, C 488 kN, C0 2240 kN, Pu 46.5 kN. reference speed 750 r/min (thermal) and limiting speed 1,100 r/min (mechanical), catalogue mass 25000 g. Pitch-diameter arithmetic: dm = (260+360)/2 = 310.0 mm; at the 1,100 r/min limiting speed that corresponds to roughly 341k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Speed-ratio note for this exact unit: the reference speed is 750 r/min against a 1,100 r/min limiting speed, a reference-to-limit ratio of 0.68. Sizing arithmetic on the 260 mm bore: 488 kN C over the 50.0 mm radial section gives 9.8 kN per section millimetre, and the 79 mm stack height is 1.58× that section — proportions typical of a 51200 thrust section. Light-load floor: Pu = 46.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51252 M; the number is 10 % of the 488 kN dynamic rating. Speed planning separates the two ceilings mechanically: the pressed brass cage and balls tolerate 1,100 r/min while thermal balance under catalogue load sets the 750 r/min reference; at dm ≈ 310.0 mm the corresponding dn is approximately 341k mm·r/min. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 25000 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 260 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "large press rams and screwdown mechanisms", "very heavy crane and ladle hooks", "marine gearbox thrust positions" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 24; for 51252 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 488/2240 kN and the available 360 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The 51252 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 260 mm shaft has to be carried by a radial bearing mounted alongside it.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 79 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Ordering discipline for 51252: the catalogue page quotes 51252 M and its 488/2240 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51252-M?", "a": "The catalogue envelope is 260×360×79 mm, mass 25000 g; ratings C 488 kN / C0 2240 kN / Pu 46.5 kN, reference speed 750 r/min (thermal) and limiting speed 1,100 r/min (mechanical)." }, { "q": "What does the designation 51252 M mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 52: bore 260 mm (code 52 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." }, { "q": "How is 51252-M lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 1,100 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "51252", "equiv_brand": "NTN", "level": "partial", "note": "Same 260×360×79 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51252", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51252-M", "51252 M" ], "locale_variants": {} }, { "sku": "51156-M", "brand": "SKF", "manufacturer_designation": "51156 M", "series": "51100-series", "type": "thrust_ball", "d_mm": 280, "D_mm": 350, "B_mm": 53, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 319, "static_load_kN": 1460, "fatigue_load_limit_kN": 30.5, "reference_speed_rpm": 950, "limiting_speed_rpm": 1300, "max_rpm": 1300, "weight_g": 12000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51156 M is an ISO 104 single-direction thrust ball bearing, 280 mm bore and 350 mm OD on a flat housing seat, standing 53 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 56: bore 280 mm (code 56 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. Envelope 280×350×53 mm (11.024×13.78×2.087 in), 35.0 mm radial section, C 319 kN, C0 1460 kN, Pu 30.5 kN. reference speed 950 r/min (thermal) and limiting speed 1,300 r/min (mechanical), catalogue mass 12000 g. Pitch-diameter arithmetic: dm = (280+350)/2 = 315.0 mm; at the 1,300 r/min limiting speed that corresponds to roughly 410k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Stack/annulus proportions: the 53 mm axial stack over the 34,636 mm² washer annulus gives 1.53 mm of height per annular square millimetre ×10⁻³, and at 12000 g the bearing holds about 121.7 kN of C0 per kilogram. Section proportions: the 35.0 mm radial section compares with 280 mm of bore (section/bore ≈ 0.13) and the 53 mm height is 1.51× that section — the proportions that identify the 51100 envelope at a glance. Light-load floor: Pu = 30.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51156 M; the number is 10 % of the 319 kN dynamic rating. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 11 at the 1,300 r/min limiting speed raises the required axial preload to about 1844.6 kN; the reference-speed value 985.1 kN is the thermal design point. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51156 M adds a small amount of mass and cage strength without changing the 280×350×53 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,300 r/min ceiling.", "applications": [ "heavy converter and ladle-tilt pivots", "offshore and dock winch drums", "marine gearbox thrust positions" ], "failure_modes": [ "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "track rust staining from condensate during long idle periods in humid plant air", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 319 kN track before first rotation.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 11; for 51156 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51156 against two-way load lifts the loose washer off its raceway.", "When the housing seat cannot be machined square to the 280 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "The 319/1460 kN figures belong to 51156 M specifically (the single flat brass execution of 51156); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51156-M?", "a": "The catalogue envelope is 280×350×53 mm, mass 12000 g; ratings C 319 kN / C0 1460 kN / Pu 30.5 kN, reference speed 950 r/min (thermal) and limiting speed 1,300 r/min (mechanical)." }, { "q": "What does the designation 51156 M mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 56: bore 280 mm (code 56 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51156-M need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 11 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number is a different, M-cage product) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51156", "equiv_brand": "NTN", "level": "partial", "note": "Same 280×350×53 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51156", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51156-M", "51156 M" ], "locale_variants": {} }, { "sku": "51256-M", "brand": "SKF", "manufacturer_designation": "51256 M", "series": "51200-series", "type": "thrust_ball", "d_mm": 280, "D_mm": 380, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 488, "static_load_kN": 2320, "fatigue_load_limit_kN": 47.5, "reference_speed_rpm": 750, "limiting_speed_rpm": 1000, "max_rpm": 1000, "weight_g": 26500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51256 M is SKF's 280 mm-bore single-direction thrust ball bearing in the 51200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 280×380×80 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 56 encode the bore as 280 mm (code 56 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 280×380×80 mm (11.024×14.961×3.15 in), 50.0 mm radial section, C 488 kN, C0 2320 kN, Pu 47.5 kN. reference speed 750 r/min (thermal) and limiting speed 1,000 r/min (mechanical), catalogue mass 26500 g. Speed-ratio note for this exact unit: the reference speed is 750 r/min against a 1,000 r/min limiting speed, a reference-to-limit ratio of 0.75. Imperial cross-check for procurement drawings: 11.024 in bore, 14.961 in OD, 3.15 in height, and the 26500 g catalogue mass converts to 26.500 kg (934.7 oz). Rating split for documentation: dynamic 488 kN (L10 life), static 2320 kN (safety factor s0), fatigue limit 47.5 kN (adjusted life) — three different uses of three different numbers for 51256 M, none interchangeable with another. Speed planning separates the two ceilings mechanically: the pressed brass cage and balls tolerate 1,000 r/min while thermal balance under catalogue load sets the 750 r/min reference; at dm ≈ 330.0 mm the corresponding dn is approximately 330k mm·r/min. Capacity density: 488 kN C from 26.500 kg of bearing steel gives about 18.4 kN per kilogram; static density is correspondingly 87.5 kN/kg at C0 2320 kN. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51256 M adds a small amount of mass and cage strength without changing the 280×380×80 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,000 r/min ceiling.", "applications": [ "heavy converter and ladle-tilt pivots", "very heavy crane and ladle hooks", "large press rams and screwdown mechanisms" ], "failure_modes": [ "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 488/2320 kN and the available 380 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 28; for 51256 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 280 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 80 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Ordering discipline for 51256: the catalogue page quotes 51256 M and its 488/2320 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51256-M?", "a": "51256 M measures 280 mm bore × 380 mm OD × 80 mm bearing height (11.024 × 14.961 × 3.15 in), mass about 26500 g. SKF 17000 ratings: C 488 kN, C0 2320 kN, Pu 47.5 kN, reference speed 750 r/min (thermal) and limiting speed 1,000 r/min (mechanical)." }, { "q": "What does the designation 51256 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 56 encode the bore as 280 mm (code 56 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51256-M?", "a": "The 750 r/min reference speed is the thermal balance under catalogue load; the 1,000 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51256-M need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 28 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51256", "equiv_brand": "NTN", "level": "partial", "note": "Same 280×380×80 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51256", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51256-M", "51256 M" ], "locale_variants": {} }, { "sku": "51160-M", "brand": "SKF", "manufacturer_designation": "51160 M", "series": "51100-series", "type": "thrust_ball", "d_mm": 300, "D_mm": 380, "B_mm": 62, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 364, "static_load_kN": 1760, "fatigue_load_limit_kN": 35.5, "reference_speed_rpm": 850, "limiting_speed_rpm": 1200, "max_rpm": 1200, "weight_g": 17500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51160 M is an ISO 104 single-direction thrust ball bearing, 300 mm bore and 380 mm OD on a flat housing seat, standing 62 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 60: bore 300 mm (code 60 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. Envelope 300×380×62 mm (11.811×14.961×2.441 in), 40.0 mm radial section, C 364 kN, C0 1760 kN, Pu 35.5 kN. reference speed 850 r/min (thermal) and limiting speed 1,200 r/min (mechanical), catalogue mass 17500 g. Bore-to-OD planning: OD 380 over bore 300 is a 1.27× step for this size, and the 62 mm height gives a bore/height ratio of 4.84; use these ratios when the housing recess around the 300 mm shaft is the first constraint. Envelope economics: the 62 mm axial height over a 40.0 mm radial section yields 5.9 kN of dynamic capacity per height millimetre, and the bearing weighs 17500 g for 364 kN C — about 48 g per rated kN. Section proportions: the 40.0 mm radial section compares with 300 mm of bore (section/bore ≈ 0.13) and the 62 mm height is 1.55× that section — the proportions that identify the 51100 envelope at a glance. Speed band width for this size is 350 r/min between reference and limiting (1.41× ratio); lubrication, preload and heat removal decide where inside that band 51160 M can actually run. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51160 M covers about 42,726 mm², distributing C0 1760 kN over a mean track circle of π·dm ≈ 1,068 mm. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51160 M adds a small amount of mass and cage strength without changing the 300×380×62 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,200 r/min ceiling.", "applications": [ "very heavy crane and ladle hooks", "offshore and dock winch drums", "heavy converter and ladle-tilt pivots" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "washer face scoring from swarf trapped between the loose housing washer and its register" ], "pitfalls": [ "The 51160 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 300 mm shaft has to be carried by a radial bearing mounted alongside it.", "When the housing seat cannot be machined square to the 300 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 62 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 364 kN track before first rotation.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51160 M as the single flat brass execution; other order numbers of the 51160 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51160-M?", "a": "The catalogue envelope is 300×380×62 mm, mass 17500 g; ratings C 364 kN / C0 1760 kN / Pu 35.5 kN, reference speed 850 r/min (thermal) and limiting speed 1,200 r/min (mechanical)." }, { "q": "What does the designation 51160 M mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 60: bore 300 mm (code 60 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51160-M?", "a": "The 850 r/min reference speed is the thermal balance under catalogue load; the 1,200 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51160-M need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 16 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51160", "equiv_brand": "NTN", "level": "partial", "note": "Same 300×380×62 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51160", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51160-M", "51160 M" ], "locale_variants": {} }, { "sku": "51260-M", "brand": "SKF", "manufacturer_designation": "51260 M", "series": "51200-series", "type": "thrust_ball", "d_mm": 300, "D_mm": 420, "B_mm": 95, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 585, "static_load_kN": 3000, "fatigue_load_limit_kN": 57, "reference_speed_rpm": 630, "limiting_speed_rpm": 850, "max_rpm": 850, "weight_g": 42000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51200 series order number 51260 M is a SKF single-direction thrust ball bearing for a 300 mm seat, built to ISO 104, with a flat housing seating surface, 300×420×95 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 60 decodes to 300 mm (code 60 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 300×420×95 mm (11.811×16.535×3.74 in), 60.0 mm radial section, C 585 kN, C0 3000 kN, Pu 57 kN. reference speed 630 r/min (thermal) and limiting speed 850 r/min (mechanical), catalogue mass 42000 g. Envelope economics: the 95 mm axial height over a 60.0 mm radial section yields 6.2 kN of dynamic capacity per height millimetre, and the bearing weighs 42000 g for 585 kN C — about 72 g per rated kN. Minimum-load arithmetic: with dm ≈ 360.0 mm and factor A 47, Fam ≈ A·(n·dm/1000)² at the 630 r/min reference speed is about 2417.6 kN for 51260 M; below that preload the balls skid and smear the tracks. Sizing arithmetic on the 300 mm bore: 585 kN C over the 60.0 mm radial section gives 9.8 kN per section millimetre, and the 95 mm stack height is 1.58× that section — proportions typical of a 51200 thrust section. Load balance: C0 3000 kN against C 585 kN gives a 5.13 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 57 kN enters the adjusted-life check. Mass and section check: 42000 g inside the 300×420×95 mm outline leaves a 60.0 mm radial section, and the 3000 kN static rating is 5.13× the dynamic rating — plan static safety and minimum preload against those figures. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 42000 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 300 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "heavy converter and ladle-tilt pivots", "very heavy crane and ladle hooks", "large press rams and screwdown mechanisms" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "false brinelling of the stationary tracks while the machine stands under vibration", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51260 against two-way load lifts the loose washer off its raceway.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 95 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 47; for 51260 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "When the housing seat cannot be machined square to the 300 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51200 bearing.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51260 M as the single flat brass execution; other order numbers of the 51260 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51260-M?", "a": "Boundary dimensions to ISO 104: bore 300 mm, OD 420 mm, height 95 mm; weight 42000 g. Load figures from SKF 17000: dynamic 585 kN, static 3000 kN, fatigue limit 57 kN; reference speed 630 r/min (thermal) and limiting speed 850 r/min (mechanical)." }, { "q": "What does the designation 51260 M mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 60 decodes to 300 mm (code 60 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51260-M lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 850 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 300 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51260", "equiv_brand": "NTN", "level": "partial", "note": "Same 300×420×95 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51260", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51260-M", "51260 M" ], "locale_variants": {} }, { "sku": "51164-M", "brand": "SKF", "manufacturer_designation": "51164 M", "series": "51100-series", "type": "thrust_ball", "d_mm": 320, "D_mm": 400, "B_mm": 63, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 371, "static_load_kN": 1860, "fatigue_load_limit_kN": 36.5, "reference_speed_rpm": 800, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 19000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51164 M is SKF's 320 mm-bore single-direction thrust ball bearing in the 51100 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 320×400×63 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 64 encode the bore as 320 mm (code 64 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 320×400×63 mm (12.598×15.748×2.48 in), 40.0 mm radial section, C 371 kN, C0 1860 kN, Pu 36.5 kN. reference speed 800 r/min (thermal) and limiting speed 1,100 r/min (mechanical), catalogue mass 19000 g. Speed band width for this size is 300 r/min between reference and limiting (1.38× ratio); lubrication, preload and heat removal decide where inside that band 51164 M can actually run. Imperial cross-check for procurement drawings: 12.598 in bore, 15.748 in OD, 2.48 in height, and the 19000 g catalogue mass converts to 19.000 kg (670.2 oz). Minimum-load arithmetic: with dm ≈ 360.0 mm and factor A 18, Fam ≈ A·(n·dm/1000)² at the 800 r/min reference speed is about 1493.0 kN for 51164 M; below that preload the balls skid and smear the tracks. Load balance: C0 1860 kN against C 371 kN gives a 5.01 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 36.5 kN enters the adjusted-life check. At the printed limiting speed of 1,100 r/min the mean pitch diameter dm ≈ 360.0 mm implies a dn value around 396k mm·r/min; the 800 r/min reference speed is the thermal-planning value under catalogue load. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 19000 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 320 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "offshore and dock winch drums", "heavy converter and ladle-tilt pivots", "large press rams and screwdown mechanisms" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 63 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 371/1860 kN and the available 400 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 320 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51164 M as the single flat brass execution; other order numbers of the 51164 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51164-M?", "a": "51164 M measures 320 mm bore × 400 mm OD × 63 mm bearing height (12.598 × 15.748 × 2.48 in), mass about 19000 g. SKF 17000 ratings: C 371 kN, C0 1860 kN, Pu 36.5 kN, reference speed 800 r/min (thermal) and limiting speed 1,100 r/min (mechanical)." }, { "q": "What does the designation 51164 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 64 encode the bore as 320 mm (code 64 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." }, { "q": "How is 51164-M lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 1,100 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "51164", "equiv_brand": "NTN", "level": "partial", "note": "Same 320×400×63 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51164", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51164-M", "51164 M" ], "locale_variants": {} }, { "sku": "51264-F", "brand": "SKF", "manufacturer_designation": "51264 F", "series": "51200-series", "type": "thrust_ball", "d_mm": 320, "D_mm": 440, "B_mm": 95, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 572, "static_load_kN": 3000, "fatigue_load_limit_kN": 56, "reference_speed_rpm": 600, "limiting_speed_rpm": 800, "max_rpm": 800, "weight_g": 45500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51264 F is SKF's 320 mm-bore single-direction thrust ball bearing in the 51200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 320×440×95 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 64 encode the bore as 320 mm (code 64 × 5), the standard SKF bore-code rule shared with radial bearings. suffix F identifies a machined steel cage, ball-centred: fitted to the largest sizes of the assortment where the ball complement and centrifugal forces exceed what the stamped sheet-steel execution can guide. Envelope 320×440×95 mm (12.598×17.323×3.74 in), 60.0 mm radial section, C 572 kN, C0 3000 kN, Pu 56 kN. reference speed 600 r/min (thermal) and limiting speed 800 r/min (mechanical), catalogue mass 45500 g. Load balance: C0 3000 kN against C 572 kN gives a 5.24 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 56 kN enters the adjusted-life check. At the printed limiting speed of 800 r/min the mean pitch diameter dm ≈ 380.0 mm implies a dn value around 304k mm·r/min; the 600 r/min reference speed is the thermal-planning value under catalogue load. Light-load floor: Pu = 56 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51264 F; the number is 10 % of the 572 kN dynamic rating. Pitch-diameter arithmetic: dm = (320+440)/2 = 380.0 mm; at the 800 r/min limiting speed that corresponds to roughly 304k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Speed planning separates the two ceilings mechanically: the pressed steel cage and balls tolerate 800 r/min while thermal balance under catalogue load sets the 600 r/min reference; at dm ≈ 380.0 mm the corresponding dn is approximately 304k mm·r/min. Large-size execution note: the F machined steel cage exists because the ball complement and pitch diameter of the biggest 512-series sizes are beyond pressed-cage guidance; the steel cage is machined from solid, ball-centred, and its heavier mass must be supported by genuine oil or grease flow at start-up — never mount an F bearing dry for a trial rotation. Mounting note for the 95 mm F stack: induction-heat the shaft washer only — the machined steel cage rides the balls and must never be tapped, and first rotation should be a slow unloaded bedding run before the working thrust goes on.", "applications": [ "very heavy crane and ladle hooks", "marine gearbox thrust positions", "offshore and dock winch drums" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "machined steel cage scuffing on a dry first start-up, before grease or oil has reached the ball-centred guide surfaces", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "false brinelling of the stationary tracks while the machine stands under vibration" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 572 kN track before first rotation.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 320 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 47; for 51264 F a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The 572/3000 kN figures belong to 51264 F specifically (the single flat machined steel execution of 51264); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51264-F?", "a": "51264 F measures 320 mm bore × 440 mm OD × 95 mm bearing height (12.598 × 17.323 × 3.74 in), mass about 45500 g. SKF 17000 ratings: C 572 kN, C0 3000 kN, Pu 56 kN, reference speed 600 r/min (thermal) and limiting speed 800 r/min (mechanical)." }, { "q": "What does the designation 51264 F mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 64 encode the bore as 320 mm (code 64 × 5), the standard SKF bore-code rule shared with radial bearings. suffix F identifies a machined steel cage, ball-centred: fitted to the largest sizes of the assortment where the ball complement and centrifugal forces exceed what the stamped sheet-steel execution can guide. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." }, { "q": "How is 51264-F lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 800 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "51264-M", "equiv_brand": "SKF", "level": "full", "note": "Same 320×440×95 mm ISO 104 thrust-ball envelope with catalogue ratings within 10 %; 51264 M is the single-direction flat-seat, machined brass cage (M) execution of this size — boundary dimensions interchangeable, execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51264-F", "51264 F" ], "locale_variants": {} }, { "sku": "51264-M", "brand": "SKF", "manufacturer_designation": "51264 M", "series": "51200-series", "type": "thrust_ball", "d_mm": 320, "D_mm": 440, "B_mm": 95, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 572, "static_load_kN": 3000, "fatigue_load_limit_kN": 56, "reference_speed_rpm": 600, "limiting_speed_rpm": 800, "max_rpm": 800, "weight_g": 45000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51264 M is SKF's 320 mm-bore single-direction thrust ball bearing in the 51200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 320×440×95 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 64 encode the bore as 320 mm (code 64 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 320×440×95 mm (12.598×17.323×3.74 in), 60.0 mm radial section, C 572 kN, C0 3000 kN, Pu 56 kN. reference speed 600 r/min (thermal) and limiting speed 800 r/min (mechanical), catalogue mass 45000 g. Speed-ratio note for this exact unit: the reference speed is 600 r/min against a 800 r/min limiting speed, a reference-to-limit ratio of 0.75. Mass and section check: 45000 g inside the 320×440×95 mm outline leaves a 60.0 mm radial section, and the 3000 kN static rating is 5.24× the dynamic rating — plan static safety and minimum preload against those figures. Minimum-load arithmetic: with dm ≈ 380.0 mm and factor A 47, Fam ≈ A·(n·dm/1000)² at the 600 r/min reference speed is about 2443.2 kN for 51264 M; below that preload the balls skid and smear the tracks. Sizing arithmetic on the 320 mm bore: 572 kN C over the 60.0 mm radial section gives 9.5 kN per section millimetre, and the 95 mm stack height is 1.58× that section — proportions typical of a 51200 thrust section. Load balance: C0 3000 kN against C 572 kN gives a 5.24 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 56 kN enters the adjusted-life check. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 45000 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 320 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "large press rams and screwdown mechanisms", "marine gearbox thrust positions", "offshore and dock winch drums" ], "failure_modes": [ "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 47; for 51264 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 320 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51264 against two-way load lifts the loose washer off its raceway.", "The 51264 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 320 mm shaft has to be carried by a radial bearing mounted alongside it.", "Ordering discipline for 51264: the catalogue page quotes 51264 M and its 572/3000 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51264-M?", "a": "51264 M measures 320 mm bore × 440 mm OD × 95 mm bearing height (12.598 × 17.323 × 3.74 in), mass about 45000 g. SKF 17000 ratings: C 572 kN, C0 3000 kN, Pu 56 kN, reference speed 600 r/min (thermal) and limiting speed 800 r/min (mechanical)." }, { "q": "What does the designation 51264 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 64 encode the bore as 320 mm (code 64 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51264-M need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 47 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number is a different, M-cage product) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51264-F", "equiv_brand": "SKF", "level": "full", "note": "Same 320×440×95 mm ISO 104 thrust-ball envelope with catalogue ratings within 10 %; 51264 F is the single-direction flat-seat, machined steel ball-centred cage (F) execution of this size — boundary dimensions interchangeable, execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51264-M", "51264 M" ], "locale_variants": {} }, { "sku": "51168-M", "brand": "SKF", "manufacturer_designation": "51168 M", "series": "51100-series", "type": "thrust_ball", "d_mm": 340, "D_mm": 420, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 377, "static_load_kN": 1960, "fatigue_load_limit_kN": 37.5, "reference_speed_rpm": 800, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 20500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51168 M is SKF's 340 mm-bore single-direction thrust ball bearing in the 51100 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 340×420×64 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 68 encode the bore as 340 mm (code 68 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 340×420×64 mm (13.386×16.535×2.52 in), 40.0 mm radial section, C 377 kN, C0 1960 kN, Pu 37.5 kN. reference speed 800 r/min (thermal) and limiting speed 1,100 r/min (mechanical), catalogue mass 20500 g. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 20 at the 1,100 r/min limiting speed raises the required axial preload to about 3494.5 kN; the reference-speed value 1848.3 kN is the thermal design point. At the printed limiting speed of 1,100 r/min the mean pitch diameter dm ≈ 380.0 mm implies a dn value around 418k mm·r/min; the 800 r/min reference speed is the thermal-planning value under catalogue load. Speed band width for this size is 300 r/min between reference and limiting (1.38× ratio); lubrication, preload and heat removal decide where inside that band 51168 M can actually run. Light-load floor: Pu = 37.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51168 M; the number is 10 % of the 377 kN dynamic rating. Static-first selection data: 1960 kN C0 spread across the 64 mm stack gives 30.6 kN of static rating per height millimetre, and the 20500 g mass/C0 ratio is about 10 g per static kN — crane-hook and screw positions are normally sized on these two figures. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. At 20500 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 340 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.", "applications": [ "marine gearbox thrust positions", "very heavy crane and ladle hooks", "offshore and dock winch drums" ], "failure_modes": [ "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "brass cage-pocket smearing during long unloaded running with a marginal oil film", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 20; for 51168 M a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 377/1960 kN and the available 420 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The 51168 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 340 mm shaft has to be carried by a radial bearing mounted alongside it.", "Ordering discipline for 51168: the catalogue page quotes 51168 M and its 377/1960 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51168-M?", "a": "51168 M measures 340 mm bore × 420 mm OD × 64 mm bearing height (13.386 × 16.535 × 2.52 in), mass about 20500 g. SKF 17000 ratings: C 377 kN, C0 1960 kN, Pu 37.5 kN, reference speed 800 r/min (thermal) and limiting speed 1,100 r/min (mechanical)." }, { "q": "What does the designation 51168 M mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 68 encode the bore as 340 mm (code 68 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51168-M?", "a": "The 800 r/min reference speed is the thermal balance under catalogue load; the 1,100 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51168-M need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 20 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51168", "equiv_brand": "NTN", "level": "partial", "note": "Same 340×420×64 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51168", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51168-M", "51168 M" ], "locale_variants": {} }, { "sku": "51268-F", "brand": "SKF", "manufacturer_designation": "51268 F", "series": "51200-series", "type": "thrust_ball", "d_mm": 340, "D_mm": 460, "B_mm": 96, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 605, "static_load_kN": 3200, "fatigue_load_limit_kN": 25.5, "reference_speed_rpm": 600, "limiting_speed_rpm": 800, "max_rpm": 800, "weight_g": 48500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51200 series order number 51268 F is a SKF single-direction thrust ball bearing for a 340 mm seat, built to ISO 104, with a flat housing seating surface, 340×460×96 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 68 decodes to 340 mm (code 68 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the F suffix denotes a steel cage machined from solid and centred on the balls, reserved for the largest OD sizes whose ball mass is beyond pressed-cage guidance. Envelope 340×460×96 mm (13.386×18.11×3.78 in), 60.0 mm radial section, C 605 kN, C0 3200 kN, Pu 25.5 kN. reference speed 600 r/min (thermal) and limiting speed 800 r/min (mechanical), catalogue mass 48500 g. Selection figures for 51268 F: the C0/C ratio is 5.29, Pu 25.5 kN is about 4 % of C, and the catalogue mass works out to roughly 143 g per millimetre of bore; the printed minimum-load factor is A 53. Speed planning separates the two ceilings mechanically: the pressed steel cage and balls tolerate 800 r/min while thermal balance under catalogue load sets the 600 r/min reference; at dm ≈ 400.0 mm the corresponding dn is approximately 320k mm·r/min. Track-circle loading: per millimetre of mean track circumference the 605 kN dynamic rating corresponds to roughly 0.48 kN/mm of π·dm track, a useful comparison against the other dimension series of the 340 mm bore. Rating split for documentation: dynamic 605 kN (L10 life), static 3200 kN (safety factor s0), fatigue limit 25.5 kN (adjusted life) — three different uses of three different numbers for 51268 F, none interchangeable with another. At the printed limiting speed of 800 r/min the mean pitch diameter dm ≈ 400.0 mm implies a dn value around 320k mm·r/min; the 600 r/min reference speed is the thermal-planning value under catalogue load. Large-size execution note: the F machined steel cage exists because the ball complement and pitch diameter of the biggest 512-series sizes are beyond pressed-cage guidance; the steel cage is machined from solid, ball-centred, and its heavier mass must be supported by genuine oil or grease flow at start-up — never mount an F bearing dry for a trial rotation. The F execution appears only at the 340 mm top end of the range: the 460 mm OD ball complement is large enough that cage centrifugal forces dictate a machined guide, which is also why the 3200 kN C0 figure dominates selection of this order number.", "applications": [ "offshore and dock winch drums", "very heavy crane and ladle hooks", "marine gearbox thrust positions" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "machined steel cage scuffing on a dry first start-up, before grease or oil has reached the ball-centred guide surfaces", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 53; for 51268 F a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The 51268 F is a pure axial bearing: it must never be subjected to radial load — any radial force on the 340 mm shaft has to be carried by a radial bearing mounted alongside it.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 340 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 605 kN track before first rotation.", "Ordering discipline for 51268: the catalogue page quotes 51268 F and its 605/3200 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51268-F?", "a": "Boundary dimensions to ISO 104: bore 340 mm, OD 460 mm, height 96 mm; weight 48500 g. Load figures from SKF 17000: dynamic 605 kN, static 3200 kN, fatigue limit 25.5 kN; reference speed 600 r/min (thermal) and limiting speed 800 r/min (mechanical)." }, { "q": "What does the designation 51268 F mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 68 decodes to 340 mm (code 68 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the F suffix denotes a steel cage machined from solid and centred on the balls, reserved for the largest OD sizes whose ball mass is beyond pressed-cage guidance. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51268-F?", "a": "The 600 r/min reference speed is the thermal balance under catalogue load; the 800 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51268-F need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 53 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51268", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51268-F", "51268 F" ], "locale_variants": {} }, { "sku": "51172-F", "brand": "SKF", "manufacturer_designation": "51172 F", "series": "51100-series", "type": "thrust_ball", "d_mm": 360, "D_mm": 440, "B_mm": 65, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 390, "static_load_kN": 2080, "fatigue_load_limit_kN": 38, "reference_speed_rpm": 750, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 22000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51172 F is a SKF single-direction thrust ball bearing for a 360 mm seat, built to ISO 104, with a flat housing seating surface, 360×440×65 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 72 decodes to 360 mm (code 72 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the F suffix denotes a steel cage machined from solid and centred on the balls, reserved for the largest OD sizes whose ball mass is beyond pressed-cage guidance. Envelope 360×440×65 mm (14.173×17.323×2.559 in), 40.0 mm radial section, C 390 kN, C0 2080 kN, Pu 38 kN. reference speed 750 r/min (thermal) and limiting speed 1,100 r/min (mechanical), catalogue mass 22000 g. Track-circle loading: per millimetre of mean track circumference the 390 kN dynamic rating corresponds to roughly 0.31 kN/mm of π·dm track, a useful comparison against the other dimension series of the 360 mm bore. Section proportions: the 40.0 mm radial section compares with 360 mm of bore (section/bore ≈ 0.11) and the 65 mm height is 1.63× that section — the proportions that identify the 51100 envelope at a glance. Static-first selection data: 2080 kN C0 spread across the 65 mm stack gives 32.0 kN of static rating per height millimetre, and the 22000 g mass/C0 ratio is about 11 g per static kN — crane-hook and screw positions are normally sized on these two figures. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 22 at the 1,100 r/min limiting speed raises the required axial preload to about 4259.2 kN; the reference-speed value 1980.0 kN is the thermal design point. Speed band width for this size is 350 r/min between reference and limiting (1.47× ratio); lubrication, preload and heat removal decide where inside that band 51172 F can actually run. Large-size execution note: the F machined steel cage exists because the ball complement and pitch diameter of the biggest 512-series sizes are beyond pressed-cage guidance; the steel cage is machined from solid, ball-centred, and its heavier mass must be supported by genuine oil or grease flow at start-up — never mount an F bearing dry for a trial rotation. The F execution appears only at the 360 mm top end of the range: the 440 mm OD ball complement is large enough that cage centrifugal forces dictate a machined guide, which is also why the 2080 kN C0 figure dominates selection of this order number.", "applications": [ "offshore and dock winch drums", "very heavy crane and ladle hooks", "marine gearbox thrust positions" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "machined steel cage scuffing on a dry first start-up, before grease or oil has reached the ball-centred guide surfaces", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 390 kN track before first rotation.", "When the housing seat cannot be machined square to the 360 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 22; for 51172 F a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 390/2080 kN and the available 440 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The 390/2080 kN figures belong to 51172 F specifically (the single flat machined steel execution of 51172); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51172-F?", "a": "Boundary dimensions to ISO 104: bore 360 mm, OD 440 mm, height 65 mm; weight 22000 g. Load figures from SKF 17000: dynamic 390 kN, static 2080 kN, fatigue limit 38 kN; reference speed 750 r/min (thermal) and limiting speed 1,100 r/min (mechanical)." }, { "q": "What does the designation 51172 F mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 72 decodes to 360 mm (code 72 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the F suffix denotes a steel cage machined from solid and centred on the balls, reserved for the largest OD sizes whose ball mass is beyond pressed-cage guidance. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number is a different, F-cage product) uses the standard stamped sheet-steel pressed cage." }, { "q": "Can 51172-F carry radial load?", "a": "No — thrust ball bearings are designed for pure axial load. Any radial force on the 360 mm shaft must go to a separate radial bearing; mixed loading through 51172 F edge-loads the balls and destroys the washers." } ], "cross_ref": [ { "equiv_sku": "51172", "equiv_brand": "NTN", "level": "partial", "note": "Same 360×440×65 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51172", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51172-F", "51172 F" ], "locale_variants": {} }, { "sku": "51272-F", "brand": "SKF", "manufacturer_designation": "51272 F", "series": "51200-series", "type": "thrust_ball", "d_mm": 360, "D_mm": 500, "B_mm": 110, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 741, "static_load_kN": 4150, "fatigue_load_limit_kN": 73.5, "reference_speed_rpm": 500, "limiting_speed_rpm": 700, "max_rpm": 700, "weight_g": 70000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51200 series order number 51272 F is a SKF single-direction thrust ball bearing for a 360 mm seat, built to ISO 104, with a flat housing seating surface, 360×500×110 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 72 decodes to 360 mm (code 72 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the F suffix denotes a steel cage machined from solid and centred on the balls, reserved for the largest OD sizes whose ball mass is beyond pressed-cage guidance. Envelope 360×500×110 mm (14.173×19.685×4.331 in), 70.0 mm radial section, C 741 kN, C0 4150 kN, Pu 73.5 kN. reference speed 500 r/min (thermal) and limiting speed 700 r/min (mechanical), catalogue mass 70000 g. Pitch-diameter arithmetic: dm = (360+500)/2 = 430.0 mm; at the 700 r/min limiting speed that corresponds to roughly 301k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Light-load floor: Pu = 73.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51272 F; the number is 10 % of the 741 kN dynamic rating. Bore-to-OD planning: OD 500 over bore 360 is a 1.39× step for this size, and the 110 mm height gives a bore/height ratio of 3.27; use these ratios when the housing recess around the 360 mm shaft is the first constraint. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 90 at the 700 r/min limiting speed raises the required axial preload to about 8154.1 kN; the reference-speed value 4160.3 kN is the thermal design point. Sizing arithmetic on the 360 mm bore: 741 kN C over the 70.0 mm radial section gives 10.6 kN per section millimetre, and the 110 mm stack height is 1.57× that section — proportions typical of a 51200 thrust section. Large-size execution note: the F machined steel cage exists because the ball complement and pitch diameter of the biggest 512-series sizes are beyond pressed-cage guidance; the steel cage is machined from solid, ball-centred, and its heavier mass must be supported by genuine oil or grease flow at start-up — never mount an F bearing dry for a trial rotation. The F execution appears only at the 360 mm top end of the range: the 500 mm OD ball complement is large enough that cage centrifugal forces dictate a machined guide, which is also why the 4150 kN C0 figure dominates selection of this order number.", "applications": [ "offshore and dock winch drums", "heavy converter and ladle-tilt pivots", "very heavy crane and ladle hooks" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "machined steel cage scuffing on a dry first start-up, before grease or oil has reached the ball-centred guide surfaces", "washer face scoring from swarf trapped between the loose housing washer and its register", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 90; for 51272 F a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 360 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "The 51272 F is a pure axial bearing: it must never be subjected to radial load — any radial force on the 360 mm shaft has to be carried by a radial bearing mounted alongside it.", "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 741 kN track before first rotation.", "Ordering discipline for 51272: the catalogue page quotes 51272 F and its 741/4150 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51272-F?", "a": "Boundary dimensions to ISO 104: bore 360 mm, OD 500 mm, height 110 mm; weight 70000 g. Load figures from SKF 17000: dynamic 741 kN, static 4150 kN, fatigue limit 73.5 kN; reference speed 500 r/min (thermal) and limiting speed 700 r/min (mechanical)." }, { "q": "What does the designation 51272 F mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 72 decodes to 360 mm (code 72 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the F suffix denotes a steel cage machined from solid and centred on the balls, reserved for the largest OD sizes whose ball mass is beyond pressed-cage guidance. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51272-F need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 90 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number is a different, F-cage product) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51272", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51272-F", "51272 F" ], "locale_variants": {} }, { "sku": "51176-F", "brand": "SKF", "manufacturer_designation": "51176 F", "series": "51100-series", "type": "thrust_ball", "d_mm": 380, "D_mm": 460, "B_mm": 65, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 397, "static_load_kN": 2200, "fatigue_load_limit_kN": 40, "reference_speed_rpm": 750, "limiting_speed_rpm": 1000, "max_rpm": 1000, "weight_g": 23000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51176 F is an ISO 104 single-direction thrust ball bearing, 380 mm bore and 460 mm OD on a flat housing seat, standing 65 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 76: bore 380 mm (code 76 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. F-cage execution: a solid machined steel ball-centred retainer for the biggest thrust-ball sizes, where rigidity and cage guidance dominate over the lightness of sheet steel. Envelope 380×460×65 mm (14.961×18.11×2.559 in), 40.0 mm radial section, C 397 kN, C0 2200 kN, Pu 40 kN. reference speed 750 r/min (thermal) and limiting speed 1,000 r/min (mechanical), catalogue mass 23000 g. At the printed limiting speed of 1,000 r/min the mean pitch diameter dm ≈ 420.0 mm implies a dn value around 420k mm·r/min; the 750 r/min reference speed is the thermal-planning value under catalogue load. Section proportions: the 40.0 mm radial section compares with 380 mm of bore (section/bore ≈ 0.11) and the 65 mm height is 1.63× that section — the proportions that identify the 51100 envelope at a glance. Sizing arithmetic on the 380 mm bore: 397 kN C over the 40.0 mm radial section gives 9.9 kN per section millimetre, and the 65 mm stack height is 1.63× that section — proportions typical of a 51100 thrust section. Pitch-diameter arithmetic: dm = (380+460)/2 = 420.0 mm; at the 1,000 r/min limiting speed that corresponds to roughly 420k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51176 F covers about 52,779 mm², distributing C0 2200 kN over a mean track circle of π·dm ≈ 1,319 mm. Large-size execution note: the F machined steel cage exists because the ball complement and pitch diameter of the biggest 512-series sizes are beyond pressed-cage guidance; the steel cage is machined from solid, ball-centred, and its heavier mass must be supported by genuine oil or grease flow at start-up — never mount an F bearing dry for a trial rotation. The F execution appears only at the 380 mm top end of the range: the 460 mm OD ball complement is large enough that cage centrifugal forces dictate a machined guide, which is also why the 2200 kN C0 figure dominates selection of this order number.", "applications": [ "offshore and dock winch drums", "heavy converter and ladle-tilt pivots", "large press rams and screwdown mechanisms" ], "failure_modes": [ "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "machined steel cage scuffing on a dry first start-up, before grease or oil has reached the ball-centred guide surfaces", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "washer face scoring from swarf trapped between the loose housing washer and its register" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 65 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 380 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 25; for 51176 F a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51176 F as the single flat machined steel execution; other order numbers of the 51176 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51176-F?", "a": "The catalogue envelope is 380×460×65 mm, mass 23000 g; ratings C 397 kN / C0 2200 kN / Pu 40 kN, reference speed 750 r/min (thermal) and limiting speed 1,000 r/min (mechanical)." }, { "q": "What does the designation 51176 F mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 76: bore 380 mm (code 76 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. F-cage execution: a solid machined steel ball-centred retainer for the biggest thrust-ball sizes, where rigidity and cage guidance dominate over the lightness of sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 380 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." }, { "q": "Can a single 51176 take thrust in both directions?", "a": "No. It reacts axial force in one direction; reversing duty needs a mirrored pair of single-direction bearings or a 52-series double-direction unit, which packages one shaft washer, two housing washers and two cage sets." } ], "cross_ref": [ { "equiv_sku": "51176", "equiv_brand": "NTN", "level": "partial", "note": "Same 380×460×65 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51176", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51176-F", "51176 F" ], "locale_variants": {} }, { "sku": "51276-F", "brand": "SKF", "manufacturer_designation": "51276 F", "series": "51200-series", "type": "thrust_ball", "d_mm": 380, "D_mm": 520, "B_mm": 112, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 728, "static_load_kN": 4150, "fatigue_load_limit_kN": 72, "reference_speed_rpm": 500, "limiting_speed_rpm": 700, "max_rpm": 700, "weight_g": 73000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51276 F is SKF's 380 mm-bore single-direction thrust ball bearing in the 51200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 380×520×112 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 76 encode the bore as 380 mm (code 76 × 5), the standard SKF bore-code rule shared with radial bearings. suffix F identifies a machined steel cage, ball-centred: fitted to the largest sizes of the assortment where the ball complement and centrifugal forces exceed what the stamped sheet-steel execution can guide. Envelope 380×520×112 mm (14.961×20.472×4.409 in), 70.0 mm radial section, C 728 kN, C0 4150 kN, Pu 72 kN. reference speed 500 r/min (thermal) and limiting speed 700 r/min (mechanical), catalogue mass 73000 g. Bore-to-OD planning: OD 520 over bore 380 is a 1.37× step for this size, and the 112 mm height gives a bore/height ratio of 3.39; use these ratios when the housing recess around the 380 mm shaft is the first constraint. Mass and section check: 73000 g inside the 380×520×112 mm outline leaves a 70.0 mm radial section, and the 4150 kN static rating is 5.70× the dynamic rating — plan static safety and minimum preload against those figures. Rating split for documentation: dynamic 728 kN (L10 life), static 4150 kN (safety factor s0), fatigue limit 72 kN (adjusted life) — three different uses of three different numbers for 51276 F, none interchangeable with another. Sizing arithmetic on the 380 mm bore: 728 kN C over the 70.0 mm radial section gives 10.4 kN per section millimetre, and the 112 mm stack height is 1.60× that section — proportions typical of a 51200 thrust section. Imperial cross-check for procurement drawings: 14.961 in bore, 20.472 in OD, 4.409 in height, and the 73000 g catalogue mass converts to 73.000 kg (2575.0 oz). Large-size execution note: the F machined steel cage exists because the ball complement and pitch diameter of the biggest 512-series sizes are beyond pressed-cage guidance; the steel cage is machined from solid, ball-centred, and its heavier mass must be supported by genuine oil or grease flow at start-up — never mount an F bearing dry for a trial rotation. Mounting note for the 112 mm F stack: induction-heat the shaft washer only — the machined steel cage rides the balls and must never be tapped, and first rotation should be a slow unloaded bedding run before the working thrust goes on.", "applications": [ "large press rams and screwdown mechanisms", "very heavy crane and ladle hooks", "marine gearbox thrust positions" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "machined steel cage scuffing on a dry first start-up, before grease or oil has reached the ball-centred guide surfaces", "false brinelling of the stationary tracks while the machine stands under vibration", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 728 kN track before first rotation.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 112 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51276 against two-way load lifts the loose washer off its raceway.", "The 728/4150 kN figures belong to 51276 F specifically (the single flat machined steel execution of 51276); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51276-F?", "a": "51276 F measures 380 mm bore × 520 mm OD × 112 mm bearing height (14.961 × 20.472 × 4.409 in), mass about 73000 g. SKF 17000 ratings: C 728 kN, C0 4150 kN, Pu 72 kN, reference speed 500 r/min (thermal) and limiting speed 700 r/min (mechanical)." }, { "q": "What does the designation 51276 F mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 76 encode the bore as 380 mm (code 76 × 5), the standard SKF bore-code rule shared with radial bearings. suffix F identifies a machined steel cage, ball-centred: fitted to the largest sizes of the assortment where the ball complement and centrifugal forces exceed what the stamped sheet-steel execution can guide. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51276-F lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 700 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 380 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51276", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51276-F", "51276 F" ], "locale_variants": {} }, { "sku": "51180-F", "brand": "SKF", "manufacturer_designation": "51180 F", "series": "51100-series", "type": "thrust_ball", "d_mm": 400, "D_mm": 480, "B_mm": 65, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 403, "static_load_kN": 2280, "fatigue_load_limit_kN": 40.5, "reference_speed_rpm": 700, "limiting_speed_rpm": 1000, "max_rpm": 1000, "weight_g": 24000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 51180 F is an ISO 104 single-direction thrust ball bearing, 400 mm bore and 480 mm OD on a flat housing seat, standing 65 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 80: bore 400 mm (code 80 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. F-cage execution: a solid machined steel ball-centred retainer for the biggest thrust-ball sizes, where rigidity and cage guidance dominate over the lightness of sheet steel. Envelope 400×480×65 mm (15.748×18.898×2.559 in), 40.0 mm radial section, C 403 kN, C0 2280 kN, Pu 40.5 kN. reference speed 700 r/min (thermal) and limiting speed 1,000 r/min (mechanical), catalogue mass 24000 g. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51180 F covers about 55,292 mm², distributing C0 2280 kN over a mean track circle of π·dm ≈ 1,382 mm. Mass and section check: 24000 g inside the 400×480×65 mm outline leaves a 40.0 mm radial section, and the 2280 kN static rating is 5.66× the dynamic rating — plan static safety and minimum preload against those figures. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 27 at the 1,000 r/min limiting speed raises the required axial preload to about 5227.2 kN; the reference-speed value 2561.3 kN is the thermal design point. At the printed limiting speed of 1,000 r/min the mean pitch diameter dm ≈ 440.0 mm implies a dn value around 440k mm·r/min; the 700 r/min reference speed is the thermal-planning value under catalogue load. Pitch-diameter arithmetic: dm = (400+480)/2 = 440.0 mm; at the 1,000 r/min limiting speed that corresponds to roughly 440k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Large-size execution note: the F machined steel cage exists because the ball complement and pitch diameter of the biggest 512-series sizes are beyond pressed-cage guidance; the steel cage is machined from solid, ball-centred, and its heavier mass must be supported by genuine oil or grease flow at start-up — never mount an F bearing dry for a trial rotation. Mounting note for the 65 mm F stack: induction-heat the shaft washer only — the machined steel cage rides the balls and must never be tapped, and first rotation should be a slow unloaded bedding run before the working thrust goes on.", "applications": [ "heavy converter and ladle-tilt pivots", "marine gearbox thrust positions", "large press rams and screwdown mechanisms" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "machined steel cage scuffing on a dry first start-up, before grease or oil has reached the ball-centred guide surfaces", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 403/2280 kN and the available 480 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51180 against two-way load lifts the loose washer off its raceway.", "The 51180 F is a pure axial bearing: it must never be subjected to radial load — any radial force on the 400 mm shaft has to be carried by a radial bearing mounted alongside it.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 400 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Ordering discipline for 51180: the catalogue page quotes 51180 F and its 403/2280 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51180-F?", "a": "The catalogue envelope is 400×480×65 mm, mass 24000 g; ratings C 403 kN / C0 2280 kN / Pu 40.5 kN, reference speed 700 r/min (thermal) and limiting speed 1,000 r/min (mechanical)." }, { "q": "What does the designation 51180 F mean?", "a": "51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 80: bore 400 mm (code 80 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. F-cage execution: a solid machined steel ball-centred retainer for the biggest thrust-ball sizes, where rigidity and cage guidance dominate over the lightness of sheet steel. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51180-F need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 27 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number is a different, F-cage product) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51180", "equiv_brand": "NTN", "level": "partial", "note": "Same 400×480×65 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51180", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51180-F", "51180 F" ], "locale_variants": {} }, { "sku": "51184-F", "brand": "SKF", "manufacturer_designation": "51184 F", "series": "51100-series", "type": "thrust_ball", "d_mm": 420, "D_mm": 500, "B_mm": 65, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 410, "static_load_kN": 2400, "fatigue_load_limit_kN": 41.5, "reference_speed_rpm": 700, "limiting_speed_rpm": 1000, "max_rpm": 1000, "weight_g": 25500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51184 F is a SKF single-direction thrust ball bearing for a 420 mm seat, built to ISO 104, with a flat housing seating surface, 420×500×65 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 84 decodes to 420 mm (code 84 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the F suffix denotes a steel cage machined from solid and centred on the balls, reserved for the largest OD sizes whose ball mass is beyond pressed-cage guidance. Envelope 420×500×65 mm (16.535×19.685×2.559 in), 40.0 mm radial section, C 410 kN, C0 2400 kN, Pu 41.5 kN. reference speed 700 r/min (thermal) and limiting speed 1,000 r/min (mechanical), catalogue mass 25500 g. Speed band width for this size is 300 r/min between reference and limiting (1.43× ratio); lubrication, preload and heat removal decide where inside that band 51184 F can actually run. Rating split for documentation: dynamic 410 kN (L10 life), static 2400 kN (safety factor s0), fatigue limit 41.5 kN (adjusted life) — three different uses of three different numbers for 51184 F, none interchangeable with another. At the printed limiting speed of 1,000 r/min the mean pitch diameter dm ≈ 460.0 mm implies a dn value around 460k mm·r/min; the 700 r/min reference speed is the thermal-planning value under catalogue load. Mass and section check: 25500 g inside the 420×500×65 mm outline leaves a 40.0 mm radial section, and the 2400 kN static rating is 5.85× the dynamic rating — plan static safety and minimum preload against those figures. Bore-to-OD planning: OD 500 over bore 420 is a 1.19× step for this size, and the 65 mm height gives a bore/height ratio of 6.46; use these ratios when the housing recess around the 420 mm shaft is the first constraint. Large-size execution note: the F machined steel cage exists because the ball complement and pitch diameter of the biggest 512-series sizes are beyond pressed-cage guidance; the steel cage is machined from solid, ball-centred, and its heavier mass must be supported by genuine oil or grease flow at start-up — never mount an F bearing dry for a trial rotation. The F execution appears only at the 420 mm top end of the range: the 500 mm OD ball complement is large enough that cage centrifugal forces dictate a machined guide, which is also why the 2400 kN C0 figure dominates selection of this order number.", "applications": [ "heavy converter and ladle-tilt pivots", "marine gearbox thrust positions", "large press rams and screwdown mechanisms" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "machined steel cage scuffing on a dry first start-up, before grease or oil has reached the ball-centred guide surfaces", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51184 against two-way load lifts the loose washer off its raceway.", "When the housing seat cannot be machined square to the 420 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 30; for 51184 F a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 420 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51184 F as the single flat machined steel execution; other order numbers of the 51184 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51184-F?", "a": "Boundary dimensions to ISO 104: bore 420 mm, OD 500 mm, height 65 mm; weight 25500 g. Load figures from SKF 17000: dynamic 410 kN, static 2400 kN, fatigue limit 41.5 kN; reference speed 700 r/min (thermal) and limiting speed 1,000 r/min (mechanical)." }, { "q": "What does the designation 51184 F mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 84 decodes to 420 mm (code 84 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the F suffix denotes a steel cage machined from solid and centred on the balls, reserved for the largest OD sizes whose ball mass is beyond pressed-cage guidance. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "How is 51184-F lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 1,000 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." }, { "q": "Which way round do the washers go?", "a": "The shaft washer has the smaller, ground bore and is fitted tight on the 420 mm shaft; the housing washer has the larger loose bore and sits in the register. Load must press the shaft washer towards the housing washer through the ball-cage set — reverse fitting makes the loose washer rotate with the shaft." } ], "cross_ref": [ { "equiv_sku": "51184", "equiv_brand": "NTN", "level": "partial", "note": "Same 420×500×65 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51184", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51184-F", "51184 F" ], "locale_variants": {} }, { "sku": "51188-F", "brand": "SKF", "manufacturer_designation": "51188 F", "series": "51100-series", "type": "thrust_ball", "d_mm": 440, "D_mm": 540, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 527, "static_load_kN": 3250, "fatigue_load_limit_kN": 55, "reference_speed_rpm": 600, "limiting_speed_rpm": 850, "max_rpm": 850, "weight_g": 42000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 51100 series order number 51188 F is a SKF single-direction thrust ball bearing for a 440 mm seat, built to ISO 104, with a flat housing seating surface, 440×540×80 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 88 decodes to 440 mm (code 88 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the F suffix denotes a steel cage machined from solid and centred on the balls, reserved for the largest OD sizes whose ball mass is beyond pressed-cage guidance. Envelope 440×540×80 mm (17.323×21.26×3.15 in), 50.0 mm radial section, C 527 kN, C0 3250 kN, Pu 55 kN. reference speed 600 r/min (thermal) and limiting speed 850 r/min (mechanical), catalogue mass 42000 g. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51188 F covers about 76,969 mm², distributing C0 3250 kN over a mean track circle of π·dm ≈ 1,539 mm. Speed band width for this size is 250 r/min between reference and limiting (1.42× ratio); lubrication, preload and heat removal decide where inside that band 51188 F can actually run. Mass and section check: 42000 g inside the 440×540×80 mm outline leaves a 50.0 mm radial section, and the 3250 kN static rating is 6.17× the dynamic rating — plan static safety and minimum preload against those figures. Rating split for documentation: dynamic 527 kN (L10 life), static 3250 kN (safety factor s0), fatigue limit 55 kN (adjusted life) — three different uses of three different numbers for 51188 F, none interchangeable with another. Selection figures for 51188 F: the C0/C ratio is 6.17, Pu 55 kN is about 10 % of C, and the catalogue mass works out to roughly 95 g per millimetre of bore; the printed minimum-load factor is A 55. Large-size execution note: the F machined steel cage exists because the ball complement and pitch diameter of the biggest 512-series sizes are beyond pressed-cage guidance; the steel cage is machined from solid, ball-centred, and its heavier mass must be supported by genuine oil or grease flow at start-up — never mount an F bearing dry for a trial rotation. Mounting note for the 80 mm F stack: induction-heat the shaft washer only — the machined steel cage rides the balls and must never be tapped, and first rotation should be a slow unloaded bedding run before the working thrust goes on.", "applications": [ "marine gearbox thrust positions", "offshore and dock winch drums", "large press rams and screwdown mechanisms" ], "failure_modes": [ "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "machined steel cage scuffing on a dry first start-up, before grease or oil has reached the ball-centred guide surfaces", "track rust staining from condensate during long idle periods in humid plant air", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 80 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "When the housing seat cannot be machined square to the 440 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51100 bearing.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 527/3250 kN and the available 540 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51188 F as the single flat machined steel execution; other order numbers of the 51188 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51188-F?", "a": "Boundary dimensions to ISO 104: bore 440 mm, OD 540 mm, height 80 mm; weight 42000 g. Load figures from SKF 17000: dynamic 527 kN, static 3250 kN, fatigue limit 55 kN; reference speed 600 r/min (thermal) and limiting speed 850 r/min (mechanical)." }, { "q": "What does the designation 51188 F mean?", "a": "reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 88 decodes to 440 mm (code 88 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the F suffix denotes a steel cage machined from solid and centred on the balls, reserved for the largest OD sizes whose ball mass is beyond pressed-cage guidance. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What minimum axial load does 51188-F need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 55 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." }, { "q": "What do the M and F suffixes mean?", "a": "M is a machined brass ball-centred cage and F a machined steel ball-centred cage, both reserved for larger sizes and severer duty; the suffix-free execution (this order number is a different, F-cage product) uses the standard stamped sheet-steel pressed cage." } ], "cross_ref": [ { "equiv_sku": "51188", "equiv_brand": "NTN", "level": "partial", "note": "Same 440×540×80 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51188", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51188-F", "51188 F" ], "locale_variants": {} }, { "sku": "51192-F", "brand": "SKF", "manufacturer_designation": "51192 F", "series": "51100-series", "type": "thrust_ball", "d_mm": 460, "D_mm": 560, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 527, "static_load_kN": 3250, "fatigue_load_limit_kN": 54, "reference_speed_rpm": 600, "limiting_speed_rpm": 800, "max_rpm": 800, "weight_g": 43500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51192 F is SKF's 460 mm-bore single-direction thrust ball bearing in the 51100 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 460×560×80 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 92 encode the bore as 460 mm (code 92 × 5), the standard SKF bore-code rule shared with radial bearings. suffix F identifies a machined steel cage, ball-centred: fitted to the largest sizes of the assortment where the ball complement and centrifugal forces exceed what the stamped sheet-steel execution can guide. Envelope 460×560×80 mm (18.11×22.047×3.15 in), 50.0 mm radial section, C 527 kN, C0 3250 kN, Pu 54 kN. reference speed 600 r/min (thermal) and limiting speed 800 r/min (mechanical), catalogue mass 43500 g. Section proportions: the 50.0 mm radial section compares with 460 mm of bore (section/bore ≈ 0.11) and the 80 mm height is 1.60× that section — the proportions that identify the 51100 envelope at a glance. Imperial cross-check for procurement drawings: 18.11 in bore, 22.047 in OD, 3.15 in height, and the 43500 g catalogue mass converts to 43.500 kg (1534.4 oz). Static-first selection data: 3250 kN C0 spread across the 80 mm stack gives 40.6 kN of static rating per height millimetre, and the 43500 g mass/C0 ratio is about 13 g per static kN — crane-hook and screw positions are normally sized on these two figures. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 55 at the 800 r/min limiting speed raises the required axial preload to about 9155.5 kN; the reference-speed value 5150.0 kN is the thermal design point. Selection figures for 51192 F: the C0/C ratio is 6.17, Pu 54 kN is about 10 % of C, and the catalogue mass works out to roughly 95 g per millimetre of bore; the printed minimum-load factor is A 55. Large-size execution note: the F machined steel cage exists because the ball complement and pitch diameter of the biggest 512-series sizes are beyond pressed-cage guidance; the steel cage is machined from solid, ball-centred, and its heavier mass must be supported by genuine oil or grease flow at start-up — never mount an F bearing dry for a trial rotation. The F execution appears only at the 460 mm top end of the range: the 560 mm OD ball complement is large enough that cage centrifugal forces dictate a machined guide, which is also why the 3250 kN C0 figure dominates selection of this order number.", "applications": [ "heavy converter and ladle-tilt pivots", "large press rams and screwdown mechanisms", "offshore and dock winch drums" ], "failure_modes": [ "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "machined steel cage scuffing on a dry first start-up, before grease or oil has reached the ball-centred guide surfaces", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51192 against two-way load lifts the loose washer off its raceway.", "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 527/3250 kN and the available 560 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 460 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 51192 F as the single flat machined steel execution; other order numbers of the 51192 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51192-F?", "a": "51192 F measures 460 mm bore × 560 mm OD × 80 mm bearing height (18.11 × 22.047 × 3.15 in), mass about 43500 g. SKF 17000 ratings: C 527 kN, C0 3250 kN, Pu 54 kN, reference speed 600 r/min (thermal) and limiting speed 800 r/min (mechanical)." }, { "q": "What does the designation 51192 F mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 92 encode the bore as 460 mm (code 92 × 5), the standard SKF bore-code rule shared with radial bearings. suffix F identifies a machined steel cage, ball-centred: fitted to the largest sizes of the assortment where the ball complement and centrifugal forces exceed what the stamped sheet-steel execution can guide. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What is the difference between the 511, 512, 513 and 514 series?", "a": "All are single-direction flat-seat thrust ball bearings; the third digit grades the dimension series from light section (511) to heavy (514). At the same bore a 514 is taller, larger in OD and far higher rated than a 511, so series are not interchangeable without rechecking dimensions and ratings." }, { "q": "How is 51192-F lubricated?", "a": "Grease is standard at the small and medium end — fill the housing recess sparingly so churning does not push the loose washer off its seat; oil bath or circulation is normal near the 800 r/min limiting speed and on vertical shafts, where the upper washer would otherwise run dry." } ], "cross_ref": [ { "equiv_sku": "51192", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "51192", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51192-F", "51192 F" ], "locale_variants": {} }, { "sku": "51196-F", "brand": "SKF", "manufacturer_designation": "51196 F", "series": "51100-series", "type": "thrust_ball", "d_mm": 480, "D_mm": 580, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 540, "static_load_kN": 3550, "fatigue_load_limit_kN": 56, "reference_speed_rpm": 560, "limiting_speed_rpm": 800, "max_rpm": 800, "weight_g": 45500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "51196 F is SKF's 480 mm-bore single-direction thrust ball bearing in the 51100 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 480×580×80 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 96 encode the bore as 480 mm (code 96 × 5), the standard SKF bore-code rule shared with radial bearings. suffix F identifies a machined steel cage, ball-centred: fitted to the largest sizes of the assortment where the ball complement and centrifugal forces exceed what the stamped sheet-steel execution can guide. Envelope 480×580×80 mm (18.898×22.835×3.15 in), 50.0 mm radial section, C 540 kN, C0 3550 kN, Pu 56 kN. reference speed 560 r/min (thermal) and limiting speed 800 r/min (mechanical), catalogue mass 45500 g. Capacity density: 540 kN C from 45.500 kg of bearing steel gives about 11.9 kN per kilogram; static density is correspondingly 78.0 kN/kg at C0 3550 kN. Track-circle loading: per millimetre of mean track circumference the 540 kN dynamic rating corresponds to roughly 0.32 kN/mm of π·dm track, a useful comparison against the other dimension series of the 480 mm bore. Mass and section check: 45500 g inside the 480×580×80 mm outline leaves a 50.0 mm radial section, and the 3550 kN static rating is 6.57× the dynamic rating — plan static safety and minimum preload against those figures. Sizing arithmetic on the 480 mm bore: 540 kN C over the 50.0 mm radial section gives 10.8 kN per section millimetre, and the 80 mm stack height is 1.60× that section — proportions typical of a 51100 thrust section. At the printed limiting speed of 800 r/min the mean pitch diameter dm ≈ 530.0 mm implies a dn value around 424k mm·r/min; the 560 r/min reference speed is the thermal-planning value under catalogue load. Large-size execution note: the F machined steel cage exists because the ball complement and pitch diameter of the biggest 512-series sizes are beyond pressed-cage guidance; the steel cage is machined from solid, ball-centred, and its heavier mass must be supported by genuine oil or grease flow at start-up — never mount an F bearing dry for a trial rotation. Mounting note for the 80 mm F stack: induction-heat the shaft washer only — the machined steel cage rides the balls and must never be tapped, and first rotation should be a slow unloaded bedding run before the working thrust goes on.", "applications": [ "heavy converter and ladle-tilt pivots", "large press rams and screwdown mechanisms", "marine gearbox thrust positions" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "pitting on one track sector from a perpetually eccentric thrust line", "machined steel cage scuffing on a dry first start-up, before grease or oil has reached the ball-centred guide surfaces", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.", "A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51196 against two-way load lifts the loose washer off its raceway.", "Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 480 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.", "On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 80 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.", "The 540/3550 kN figures belong to 51196 F specifically (the single flat machined steel execution of 51196); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 51196-F?", "a": "51196 F measures 480 mm bore × 580 mm OD × 80 mm bearing height (18.898 × 22.835 × 3.15 in), mass about 45500 g. SKF 17000 ratings: C 540 kN, C0 3550 kN, Pu 56 kN, reference speed 560 r/min (thermal) and limiting speed 800 r/min (mechanical)." }, { "q": "What does the designation 51196 F mean?", "a": "in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 96 encode the bore as 480 mm (code 96 × 5), the standard SKF bore-code rule shared with radial bearings. suffix F identifies a machined steel cage, ball-centred: fitted to the largest sizes of the assortment where the ball complement and centrifugal forces exceed what the stamped sheet-steel execution can guide. 5 = thrust ball bearing, 1 = single direction with flat seating surface." }, { "q": "What do the two published speeds mean for 51196-F?", "a": "The 560 r/min reference speed is the thermal balance under catalogue load; the 800 r/min limiting speed is the mechanical cage/ball ceiling. Preload, lubrication and cooling move the real limits, so both are catalogue-condition figures." }, { "q": "What minimum axial load does 51196-F need?", "a": "SKF gives Fam ≈ A·(n·dm/1000)² with factor A 66 printed for this size; below it the balls skid. Spring preload, a cover spring or the rotor's own weight are the usual ways of meeting it at light load and high speed." } ], "cross_ref": [ { "equiv_sku": "51196", "equiv_brand": "NTN", "level": "partial", "note": "Same 480×580×80 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "51196", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "51196-F", "51196 F" ], "locale_variants": {} }, { "sku": "53201", "brand": "SKF", "manufacturer_designation": "53201", "series": "53200-series", "type": "thrust_ball", "d_mm": 12, "D_mm": 28, "B_mm": 11.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 13.3, "static_load_kN": 20.8, "fatigue_load_limit_kN": 0.765, "reference_speed_rpm": 8000, "limiting_speed_rpm": 11000, "max_rpm": 11000, "weight_g": 45, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 53201 is an ISO 104 single-direction thrust ball bearing, 12 mm bore and 28 mm OD, with a sphered housing washer and U seat washer, standing 11.4 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 01: bore 12 mm for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 12×28×11.4 mm (0.472×1.102×0.449 in), 8.0 mm radial section, C 13.3 kN, C0 20.8 kN, Pu 0.765 kN. Mounted height H1 13 mm includes the U 201 seat washer; the bearing alone is 11.4 mm high. reference speed 8,000 r/min (thermal) and limiting speed 11,000 r/min (mechanical), catalogue mass 45 g. Capacity density: 13.3 kN C from 0.045 kg of bearing steel gives about 295.6 kN per kilogram; static density is correspondingly 462.2 kN/kg at C0 20.8 kN. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.0022 at the 11,000 r/min limiting speed raises the required axial preload to about 106 N; the reference-speed value 56 N is the thermal design point. Static-first selection data: 20.8 kN C0 spread across the 11.4 mm stack gives 1.8 kN of static rating per height millimetre, and the 45 g mass/C0 ratio is about 2 g per static kN — crane-hook and screw positions are normally sized on these two figures. Pitch-diameter arithmetic: dm = (12+28)/2 = 20.0 mm; at the 11,000 r/min limiting speed that corresponds to roughly 220k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Stack/annulus proportions: the 11.4 mm axial stack over the 503 mm² washer annulus gives 22.66 mm of height per annular square millimetre ×10⁻³, and at 45 g the bearing holds about 462.2 kN of C0 per kilogram. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53201 and U 201 are two order numbers shipping as two articles; the installed 13 mm H1 rather than 11.4 mm H is the dimension the housing drawing must carry.", "applications": [ "light screw jacks with deflecting screws", "conveyor take-up screw thrusts", "appliance gearboxes on lightly stressed seats" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "tilted running after a mismatched U washer leaves only a narrow band of spherical contact", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "track rust staining from condensate during long idle periods in humid plant air", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "The shaft washer remains the tight, ground-bore component on the 12 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 201 into the register.", "Minimum axial load still applies with factor A 0.0022: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "The sphered housing washer of 53201 MUST run against the U 201 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "The 13.3/20.8 kN figures belong to 53201 specifically (the single sphered pressed steel execution of 53201); suffixed, sphered and counterpart-series order numbers are separate articles, and U 201 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53201?", "a": "The catalogue envelope is 12×28×11.4 mm plus the 1.6 mm the U 201 seat washer adds to reach H1 13 mm, mass 45 g; ratings C 13.3 kN / C0 20.8 kN / Pu 0.765 kN, reference speed 8,000 r/min (thermal) and limiting speed 11,000 r/min (mechanical)." }, { "q": "What does the designation 53201 mean?", "a": "53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 01: bore 12 mm for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "How much misalignment can 53201 accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." }, { "q": "What is the difference between H and H1?", "a": "H 11.4 mm is the height of the bearing itself; H1 13 mm is the installed height including the U 201 seat washer. Housing recesses and cover stacks must be drawn to H1, not H." } ], "cross_ref": [ { "equiv_sku": "51201-SKF", "equiv_brand": "SKF", "level": "full", "note": "Same 12×28×11.4 mm ISO 104 thrust-ball envelope with catalogue ratings within 10 %; 51201 is the single-direction flat-seat, stamped sheet-steel cage execution of this size — boundary dimensions interchangeable, execution differs. Bearing heights match, but this sphered SKF execution additionally needs its U 201 seat washer and stands 13 mm (H1) when mounted." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53201", "53201 + U 201" ], "locale_variants": {} }, { "sku": "53202", "brand": "SKF", "manufacturer_designation": "53202", "series": "53200-series", "type": "thrust_ball", "d_mm": 15, "D_mm": 32, "B_mm": 13.3, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 15.9, "static_load_kN": 25, "fatigue_load_limit_kN": 0.915, "reference_speed_rpm": 7000, "limiting_speed_rpm": 10000, "max_rpm": 10000, "weight_g": 63, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53202 is SKF's 15 mm-bore single-direction thrust ball bearing in the 53200 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 15×32×13.3 mm U 202 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 02 encode the bore as 15 mm, the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 15×32×13.3 mm (0.591×1.26×0.524 in), 8.5 mm radial section, C 15.9 kN, C0 25 kN, Pu 0.915 kN. Mounted height H1 15 mm includes the U 202 seat washer; the bearing alone is 13.3 mm high. reference speed 7,000 r/min (thermal) and limiting speed 10,000 r/min (mechanical), catalogue mass 63 g. Speed band width for this size is 3,000 r/min between reference and limiting (1.43× ratio); lubrication, preload and heat removal decide where inside that band 53202 can actually run. Washer-annulus check: the π/4·(D²−d²) contact annulus of 53202 covers about 628 mm², distributing C0 25 kN over a mean track circle of π·dm ≈ 74 mm. Capacity density: 15.9 kN C from 0.063 kg of bearing steel gives about 252.4 kN per kilogram; static density is correspondingly 396.8 kN/kg at C0 25 kN. Pitch-diameter arithmetic: dm = (15+32)/2 = 23.5 mm; at the 10,000 r/min limiting speed that corresponds to roughly 235k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Imperial cross-check for procurement drawings: 0.591 in bore, 1.26 in OD, 0.524 in height, and the 63 g catalogue mass converts to 0.063 kg (2.2 oz). Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 32 mm washer can tilt inside the U 202 seat; check the actual tilt allowance in the mounting drawing, since the 1.7 mm washer thickness step does not by itself quantify it.", "applications": [ "light screw jacks with deflecting screws", "appliance gearboxes on lightly stressed seats", "conveyor take-up screw thrusts" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "tilted running after a mismatched U washer leaves only a narrow band of spherical contact", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "raceway indentation from driving the bearing home through the ball set rather than the washer face" ], "pitfalls": [ "The shaft washer remains the tight, ground-bore component on the 15 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 202 into the register.", "Minimum axial load still applies with factor A 0.0038: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The sphered housing washer of 53202 MUST run against the U 202 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 202 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "Ordering discipline for 53202: the catalogue page quotes 53202 plus U 202 and its 15.9/25 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53202?", "a": "53202 measures 15 mm bore × 32 mm OD × 13.3 mm bearing height (0.591 × 1.26 × 0.524 in), or 15 mm mounted H1 including the U 202 seat washer, mass about 63 g. SKF 17000 ratings: C 15.9 kN, C0 25 kN, Pu 0.915 kN, reference speed 7,000 r/min (thermal) and limiting speed 10,000 r/min (mechanical)." }, { "q": "What does the designation 53202 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 02 encode the bore as 15 mm, the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." }, { "q": "How much misalignment can 53202 accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." } ], "cross_ref": [ { "equiv_sku": "53202", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53202", "53202 + U 202" ], "locale_variants": {} }, { "sku": "53203", "brand": "SKF", "manufacturer_designation": "53203", "series": "53200-series", "type": "thrust_ball", "d_mm": 17, "D_mm": 35, "B_mm": 13.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 16.3, "static_load_kN": 27, "fatigue_load_limit_kN": 1, "reference_speed_rpm": 6700, "limiting_speed_rpm": 9500, "max_rpm": 9500, "weight_g": 71, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 53203 is an ISO 104 single-direction thrust ball bearing, 17 mm bore and 35 mm OD, with a sphered housing washer and U seat washer, standing 13.2 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 03: bore 17 mm for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 17×35×13.2 mm (0.669×1.378×0.52 in), 9.0 mm radial section, C 16.3 kN, C0 27 kN, Pu 1 kN. Mounted height H1 15 mm includes the U 203 seat washer; the bearing alone is 13.2 mm high. reference speed 6,700 r/min (thermal) and limiting speed 9,500 r/min (mechanical), catalogue mass 71 g. Light-load floor: Pu = 1 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 53203; the number is 6 % of the 16.3 kN dynamic rating. Minimum-load arithmetic: with dm ≈ 26.0 mm and factor A 0.0047, Fam ≈ A·(n·dm/1000)² at the 6,700 r/min reference speed is about 143 N for 53203; below that preload the balls skid and smear the tracks. Speed-ratio note for this exact unit: the reference speed is 6,700 r/min against a 9,500 r/min limiting speed, a reference-to-limit ratio of 0.71. Pitch-diameter arithmetic: dm = (17+35)/2 = 26.0 mm; at the 9,500 r/min limiting speed that corresponds to roughly 247k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Washer-annulus check: the π/4·(D²−d²) contact annulus of 53203 covers about 735 mm², distributing C0 27 kN over a mean track circle of π·dm ≈ 82 mm. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53203 and U 203 are two order numbers shipping as two articles; the installed 15 mm H1 rather than 13.2 mm H is the dimension the housing drawing must carry.", "applications": [ "appliance gearboxes on lightly stressed seats", "small vertical motor shafts with approximate housing alignment", "conveyor take-up screw thrusts" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "total loss of the aligning function after paint, scale or abrasive dust fills the sphered contact", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "false brinelling of the stationary tracks while the machine stands under vibration", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 203 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "The sphered housing washer of 53203 MUST run against the U 203 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Minimum axial load still applies with factor A 0.0047: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "Ordering discipline for 53203: the catalogue page quotes 53203 plus U 203 and its 16.3/27 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53203?", "a": "The catalogue envelope is 17×35×13.2 mm plus the 1.8 mm the U 203 seat washer adds to reach H1 15 mm, mass 71 g; ratings C 16.3 kN / C0 27 kN / Pu 1 kN, reference speed 6,700 r/min (thermal) and limiting speed 9,500 r/min (mechanical)." }, { "q": "What does the designation 53203 mean?", "a": "53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 03: bore 17 mm for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "How much misalignment can 53203 accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." }, { "q": "What is the difference between H and H1?", "a": "H 13.2 mm is the height of the bearing itself; H1 15 mm is the installed height including the U 203 seat washer. Housing recesses and cover stacks must be drawn to H1, not H." } ], "cross_ref": [ { "equiv_sku": "53203", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53203", "53203 + U 203" ], "locale_variants": {} }, { "sku": "53204", "brand": "SKF", "manufacturer_designation": "53204", "series": "53200-series", "type": "thrust_ball", "d_mm": 20, "D_mm": 40, "B_mm": 14.7, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 21.2, "static_load_kN": 37.5, "fatigue_load_limit_kN": 1.4, "reference_speed_rpm": 5600, "limiting_speed_rpm": 8000, "max_rpm": 8000, "weight_g": 100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 53200 series order number 53204 is a SKF single-direction thrust ball bearing for a 20 mm seat, built to ISO 104, with a sphered housing washer paired to a U seat washer, 20×40×14.7 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 04 decodes to 20 mm (code 04 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 20×40×14.7 mm (0.787×1.575×0.579 in), 10.0 mm radial section, C 21.2 kN, C0 37.5 kN, Pu 1.4 kN. Mounted height H1 17 mm includes the U 204 seat washer; the bearing alone is 14.7 mm high. reference speed 5,600 r/min (thermal) and limiting speed 8,000 r/min (mechanical), catalogue mass 100 g. Static-first selection data: 37.5 kN C0 spread across the 14.7 mm stack gives 2.6 kN of static rating per height millimetre, and the 100 g mass/C0 ratio is about 3 g per static kN — crane-hook and screw positions are normally sized on these two figures. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 8,000 r/min while thermal balance under catalogue load sets the 5,600 r/min reference; at dm ≈ 30.0 mm the corresponding dn is approximately 240k mm·r/min. At the printed limiting speed of 8,000 r/min the mean pitch diameter dm ≈ 30.0 mm implies a dn value around 240k mm·r/min; the 5,600 r/min reference speed is the thermal-planning value under catalogue load. Minimum-load arithmetic: with dm ≈ 30.0 mm and factor A 0.0085, Fam ≈ A·(n·dm/1000)² at the 5,600 r/min reference speed is about 240 N for 53204; below that preload the balls skid and smear the tracks. Imperial cross-check for procurement drawings: 0.787 in bore, 1.575 in OD, 0.579 in height, and the 100 g catalogue mass converts to 0.100 kg (3.5 oz). Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53204 and U 204 are two order numbers shipping as two articles; the installed 17 mm H1 rather than 14.7 mm H is the dimension the housing drawing must carry.", "applications": [ "appliance gearboxes on lightly stressed seats", "small vertical motor shafts with approximate housing alignment", "agricultural adjustment pivots" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "edge loading on the ball set when the U seat washer is fitted with its concave face reversed", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Minimum axial load still applies with factor A 0.0085: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 204 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "The 21.2/37.5 kN figures belong to 53204 specifically (the single sphered pressed steel execution of 53204); suffixed, sphered and counterpart-series order numbers are separate articles, and U 204 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53204?", "a": "Boundary dimensions to ISO 104: bore 20 mm, OD 40 mm, height 14.7 mm (H1 17 mm installed with the U 204 seat washer); weight 100 g. Load figures from SKF 17000: dynamic 21.2 kN, static 37.5 kN, fatigue limit 1.4 kN; reference speed 5,600 r/min (thermal) and limiting speed 8,000 r/min (mechanical)." }, { "q": "What does the designation 53204 mean?", "a": "the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 04 decodes to 20 mm (code 04 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "What is the difference between H and H1?", "a": "H 14.7 mm is the height of the bearing itself; H1 17 mm is the installed height including the U 204 seat washer. Housing recesses and cover stacks must be drawn to H1, not H." }, { "q": "Why does 53204 need a U 204 seat washer?", "a": "The housing washer of 53204 has a sphered back face. The U 204 seat washer presents a matching concave face plus a flat housing face, and without it the convex washer contacts the register at a single point; the pair is what gives the bearing its initial-misalignment capacity." } ], "cross_ref": [ { "equiv_sku": "53204", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53204", "53204 + U 204" ], "locale_variants": {} }, { "sku": "53205", "brand": "SKF", "manufacturer_designation": "53205", "series": "53200-series", "type": "thrust_ball", "d_mm": 25, "D_mm": 47, "B_mm": 16.7, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 26.5, "static_load_kN": 50, "fatigue_load_limit_kN": 1.86, "reference_speed_rpm": 5000, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 53205 is an ISO 104 single-direction thrust ball bearing, 25 mm bore and 47 mm OD, with a sphered housing washer and U seat washer, standing 16.7 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 05: bore 25 mm (code 05 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 25×47×16.7 mm (0.984×1.85×0.657 in), 11.0 mm radial section, C 26.5 kN, C0 50 kN, Pu 1.86 kN. Mounted height H1 19 mm includes the U 205 seat washer; the bearing alone is 16.7 mm high. reference speed 5,000 r/min (thermal) and limiting speed 7,000 r/min (mechanical), catalogue mass 150 g. Static-first selection data: 50 kN C0 spread across the 16.7 mm stack gives 3.0 kN of static rating per height millimetre, and the 150 g mass/C0 ratio is about 3 g per static kN — crane-hook and screw positions are normally sized on these two figures. Load balance: C0 50 kN against C 26.5 kN gives a 1.89 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 1.86 kN enters the adjusted-life check. Speed band width for this size is 2,000 r/min between reference and limiting (1.40× ratio); lubrication, preload and heat removal decide where inside that band 53205 can actually run. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.015 at the 7,000 r/min limiting speed raises the required axial preload to about 953 N; the reference-speed value 486 N is the thermal design point. Pitch-diameter arithmetic: dm = (25+47)/2 = 36.0 mm; at the 7,000 r/min limiting speed that corresponds to roughly 252k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 47 mm washer can tilt inside the U 205 seat; check the actual tilt allowance in the mounting drawing, since the 2.3 mm washer thickness step does not by itself quantify it.", "applications": [ "vertical pumps with shaft-to-housing misalignment", "crane hooks whose block deflects under offset lifts", "machine-tool supports on less rigid fabricated housings" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "edge loading on the ball set when the U seat washer is fitted with its concave face reversed", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "false brinelling of the stationary tracks while the machine stands under vibration", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Replacement orders must list both 53205 and U 205: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 50 kN static-rated set.", "Dimension the housing to the 19 mm mounted height H1 (bearing plus U 205), not the 16.7 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "The shaft washer remains the tight, ground-bore component on the 25 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 205 into the register.", "Minimum axial load still applies with factor A 0.015: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "Ordering discipline for 53205: the catalogue page quotes 53205 plus U 205 and its 26.5/50 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53205?", "a": "The catalogue envelope is 25×47×16.7 mm plus the 2.3 mm the U 205 seat washer adds to reach H1 19 mm, mass 150 g; ratings C 26.5 kN / C0 50 kN / Pu 1.86 kN, reference speed 5,000 r/min (thermal) and limiting speed 7,000 r/min (mechanical)." }, { "q": "What does the designation 53205 mean?", "a": "53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 05: bore 25 mm (code 05 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "How much misalignment can 53205 accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." }, { "q": "What is the difference between H and H1?", "a": "H 16.7 mm is the height of the bearing itself; H1 19 mm is the installed height including the U 205 seat washer. Housing recesses and cover stacks must be drawn to H1, not H." } ], "cross_ref": [ { "equiv_sku": "53205", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53205", "53205 + U 205" ], "locale_variants": {} }, { "sku": "53206", "brand": "SKF", "manufacturer_designation": "53206", "series": "53200-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 52, "B_mm": 17.8, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.1, "static_load_kN": 51, "fatigue_load_limit_kN": 1.86, "reference_speed_rpm": 4500, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 180, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53206 is SKF's 30 mm-bore single-direction thrust ball bearing in the 53200 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 30×52×17.8 mm U 206 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 06 encode the bore as 30 mm (code 06 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 30×52×17.8 mm (1.181×2.047×0.701 in), 11.0 mm radial section, C 25.1 kN, C0 51 kN, Pu 1.86 kN. Mounted height H1 20 mm includes the U 206 seat washer; the bearing alone is 17.8 mm high. reference speed 4,500 r/min (thermal) and limiting speed 6,300 r/min (mechanical), catalogue mass 180 g. Load balance: C0 51 kN against C 25.1 kN gives a 2.03 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 1.86 kN enters the adjusted-life check. Washer-annulus check: the π/4·(D²−d²) contact annulus of 53206 covers about 1,417 mm², distributing C0 51 kN over a mean track circle of π·dm ≈ 129 mm. Light-load floor: Pu = 1.86 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 53206; the number is 7 % of the 25.1 kN dynamic rating. Sizing arithmetic on the 30 mm bore: 25.1 kN C over the 11.0 mm radial section gives 2.3 kN per section millimetre, and the 17.8 mm stack height is 1.62× that section — proportions typical of a 53200 thrust section. Track-circle loading: per millimetre of mean track circumference the 25.1 kN dynamic rating corresponds to roughly 0.19 kN/mm of π·dm track, a useful comparison against the other dimension series of the 30 mm bore. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 52 mm washer can tilt inside the U 206 seat; check the actual tilt allowance in the mounting drawing, since the 2.2 mm washer thickness step does not by itself quantify it.", "applications": [ "agricultural and construction-machine pivots", "machine-tool supports on less rigid fabricated housings", "vertical pumps with shaft-to-housing misalignment" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "point-contact destruction of the housing register when a sphered washer is operated directly on a flat face without its U seat washer", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "washer face scoring from swarf trapped between the loose housing washer and its register" ], "pitfalls": [ "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 206 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "Dimension the housing to the 20 mm mounted height H1 (bearing plus U 206), not the 17.8 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "Minimum axial load still applies with factor A 0.013: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53206 as the single sphered pressed steel execution; other order numbers of the 53206 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 206 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53206?", "a": "53206 measures 30 mm bore × 52 mm OD × 17.8 mm bearing height (1.181 × 2.047 × 0.701 in), or 20 mm mounted H1 including the U 206 seat washer, mass about 180 g. SKF 17000 ratings: C 25.1 kN, C0 51 kN, Pu 1.86 kN, reference speed 4,500 r/min (thermal) and limiting speed 6,300 r/min (mechanical)." }, { "q": "What does the designation 53206 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 06 encode the bore as 30 mm (code 06 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." }, { "q": "How much misalignment can 53206 accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." } ], "cross_ref": [ { "equiv_sku": "53206", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53206", "53206 + U 206" ], "locale_variants": {} }, { "sku": "53306", "brand": "SKF", "manufacturer_designation": "53306", "series": "53300-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 60, "B_mm": 22.6, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.8, "static_load_kN": 65.5, "fatigue_load_limit_kN": 2.4, "reference_speed_rpm": 3800, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 330, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53306 is SKF's 30 mm-bore single-direction thrust ball bearing in the 53300 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 30×60×22.6 mm U 306 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 06 encode the bore as 30 mm (code 06 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 30×60×22.6 mm (1.181×2.362×0.89 in), 15.0 mm radial section, C 35.8 kN, C0 65.5 kN, Pu 2.4 kN. Mounted height H1 25 mm includes the U 306 seat washer; the bearing alone is 22.6 mm high. reference speed 3,800 r/min (thermal) and limiting speed 5,300 r/min (mechanical), catalogue mass 330 g. Speed band width for this size is 1,500 r/min between reference and limiting (1.39× ratio); lubrication, preload and heat removal decide where inside that band 53306 can actually run. Mass and section check: 330 g inside the 30×60×22.6 mm outline leaves a 15.0 mm radial section, and the 65.5 kN static rating is 1.83× the dynamic rating — plan static safety and minimum preload against those figures. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 5,300 r/min while thermal balance under catalogue load sets the 3,800 r/min reference; at dm ≈ 45.0 mm the corresponding dn is approximately 239k mm·r/min. Stack/annulus proportions: the 22.6 mm axial stack over the 2,121 mm² washer annulus gives 10.66 mm of height per annular square millimetre ×10⁻³, and at 330 g the bearing holds about 198.5 kN of C0 per kilogram. Pitch-diameter arithmetic: dm = (30+60)/2 = 45.0 mm; at the 5,300 r/min limiting speed that corresponds to roughly 239k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53306 and U 306 are two order numbers shipping as two articles; the installed 25 mm H1 rather than 22.6 mm H is the dimension the housing drawing must carry.", "applications": [ "vertical pumps with shaft-to-housing misalignment", "screw-jack spindles that bend under load", "crane hooks whose block deflects under offset lifts" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "cage damage from mounting force applied through the balls instead of the washer face", "tilted running after a mismatched U washer leaves only a narrow band of spherical contact", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Replacement orders must list both 53306 and U 306: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 65.5 kN static-rated set.", "Minimum axial load still applies with factor A 0.026: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The shaft washer remains the tight, ground-bore component on the 30 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 306 into the register.", "Ordering discipline for 53306: the catalogue page quotes 53306 plus U 306 and its 35.8/65.5 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53306?", "a": "53306 measures 30 mm bore × 60 mm OD × 22.6 mm bearing height (1.181 × 2.362 × 0.89 in), or 25 mm mounted H1 including the U 306 seat washer, mass about 330 g. SKF 17000 ratings: C 35.8 kN, C0 65.5 kN, Pu 2.4 kN, reference speed 3,800 r/min (thermal) and limiting speed 5,300 r/min (mechanical)." }, { "q": "What does the designation 53306 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 06 encode the bore as 30 mm (code 06 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Why does 53306 need a U 306 seat washer?", "a": "The housing washer of 53306 has a sphered back face. The U 306 seat washer presents a matching concave face plus a flat housing face, and without it the convex washer contacts the register at a single point; the pair is what gives the bearing its initial-misalignment capacity." }, { "q": "Is the U 306 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53306 and U 306 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." } ], "cross_ref": [ { "equiv_sku": "53306", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53306", "53306 + U 306" ], "locale_variants": {} }, { "sku": "53207", "brand": "SKF", "manufacturer_designation": "53207", "series": "53200-series", "type": "thrust_ball", "d_mm": 35, "D_mm": 62, "B_mm": 19.9, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 73.5, "fatigue_load_limit_kN": 2.7, "reference_speed_rpm": 4000, "limiting_speed_rpm": 5600, "max_rpm": 5600, "weight_g": 280, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 53200 series order number 53207 is a SKF single-direction thrust ball bearing for a 35 mm seat, built to ISO 104, with a sphered housing washer paired to a U seat washer, 35×62×19.9 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 07 decodes to 35 mm (code 07 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 35×62×19.9 mm (1.378×2.441×0.783 in), 13.5 mm radial section, C 35.1 kN, C0 73.5 kN, Pu 2.7 kN. Mounted height H1 22 mm includes the U 207 seat washer; the bearing alone is 19.9 mm high. reference speed 4,000 r/min (thermal) and limiting speed 5,600 r/min (mechanical), catalogue mass 280 g. Pitch-diameter arithmetic: dm = (35+62)/2 = 48.5 mm; at the 5,600 r/min limiting speed that corresponds to roughly 272k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Envelope economics: the 19.9 mm axial height over a 13.5 mm radial section yields 1.8 kN of dynamic capacity per height millimetre, and the bearing weighs 280 g for 35.1 kN C — about 8 g per rated kN. Sizing arithmetic on the 35 mm bore: 35.1 kN C over the 13.5 mm radial section gives 2.6 kN per section millimetre, and the 19.9 mm stack height is 1.47× that section — proportions typical of a 53200 thrust section. Mass and section check: 280 g inside the 35×62×19.9 mm outline leaves a 13.5 mm radial section, and the 73.5 kN static rating is 2.09× the dynamic rating — plan static safety and minimum preload against those figures. Bore-to-OD planning: OD 62 over bore 35 is a 1.77× step for this size, and the 19.9 mm height gives a bore/height ratio of 1.76; use these ratios when the housing recess around the 35 mm shaft is the first constraint. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53207 and U 207 are two order numbers shipping as two articles; the installed 22 mm H1 rather than 19.9 mm H is the dimension the housing drawing must carry.", "applications": [ "agricultural and construction-machine pivots", "vertical pumps with shaft-to-housing misalignment", "machine-tool supports on less rigid fabricated housings" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "pitting on one track sector from a perpetually eccentric thrust line", "point-contact destruction of the housing register when a sphered washer is operated directly on a flat face without its U seat washer", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "track rust staining from condensate during long idle periods in humid plant air", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "The shaft washer remains the tight, ground-bore component on the 35 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 207 into the register.", "Minimum axial load still applies with factor A 0.028: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The sphered housing washer of 53207 MUST run against the U 207 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 207 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53207 as the single sphered pressed steel execution; other order numbers of the 53207 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 207 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53207?", "a": "Boundary dimensions to ISO 104: bore 35 mm, OD 62 mm, height 19.9 mm (H1 22 mm installed with the U 207 seat washer); weight 280 g. Load figures from SKF 17000: dynamic 35.1 kN, static 73.5 kN, fatigue limit 2.7 kN; reference speed 4,000 r/min (thermal) and limiting speed 5,600 r/min (mechanical)." }, { "q": "What does the designation 53207 mean?", "a": "the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 07 decodes to 35 mm (code 07 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Is 53207 bidirectional?", "a": "No, the 53-series is single-direction; for reversing thrust with the same self-aligning feature use the 54-series double-direction execution, which needs two U seat washers." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." } ], "cross_ref": [ { "equiv_sku": "53207", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53207", "53207 + U 207" ], "locale_variants": {} }, { "sku": "53307", "brand": "SKF", "manufacturer_designation": "53307", "series": "53300-series", "type": "thrust_ball", "d_mm": 35, "D_mm": 68, "B_mm": 25.6, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 49.4, "static_load_kN": 96.5, "fatigue_load_limit_kN": 3.55, "reference_speed_rpm": 3200, "limiting_speed_rpm": 4500, "max_rpm": 4500, "weight_g": 460, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 53307 is an ISO 104 single-direction thrust ball bearing, 35 mm bore and 68 mm OD, with a sphered housing washer and U seat washer, standing 25.6 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 07: bore 35 mm (code 07 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 35×68×25.6 mm (1.378×2.677×1.008 in), 16.5 mm radial section, C 49.4 kN, C0 96.5 kN, Pu 3.55 kN. Mounted height H1 28 mm includes the U 307 seat washer; the bearing alone is 25.6 mm high. reference speed 3,200 r/min (thermal) and limiting speed 4,500 r/min (mechanical), catalogue mass 460 g. Minimum-load arithmetic: with dm ≈ 51.5 mm and factor A 0.048, Fam ≈ A·(n·dm/1000)² at the 3,200 r/min reference speed is about 1.3 kN for 53307; below that preload the balls skid and smear the tracks. Static-first selection data: 96.5 kN C0 spread across the 25.6 mm stack gives 3.8 kN of static rating per height millimetre, and the 460 g mass/C0 ratio is about 5 g per static kN — crane-hook and screw positions are normally sized on these two figures. Pitch-diameter arithmetic: dm = (35+68)/2 = 51.5 mm; at the 4,500 r/min limiting speed that corresponds to roughly 232k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Track-circle loading: per millimetre of mean track circumference the 49.4 kN dynamic rating corresponds to roughly 0.31 kN/mm of π·dm track, a useful comparison against the other dimension series of the 35 mm bore. Washer-stack proportions: the U 307 seat washer adds 2.4 mm to the 25.6 mm bearing height for a mounted H1 of 28 mm, while the 16.5 mm radial section against 35 mm bore (section/bore ≈ 0.47) identifies the envelope. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 68 mm washer can tilt inside the U 307 seat; check the actual tilt allowance in the mounting drawing, since the 2.4 mm washer thickness step does not by itself quantify it.", "applications": [ "machine-tool supports on less rigid fabricated housings", "vertical pumps with shaft-to-housing misalignment", "crane hooks whose block deflects under offset lifts" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "tilted running after a mismatched U washer leaves only a narrow band of spherical contact", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 307 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "Dimension the housing to the 28 mm mounted height H1 (bearing plus U 307), not the 25.6 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "Minimum axial load still applies with factor A 0.048: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The 49.4/96.5 kN figures belong to 53307 specifically (the single sphered pressed steel execution of 53307); suffixed, sphered and counterpart-series order numbers are separate articles, and U 307 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53307?", "a": "The catalogue envelope is 35×68×25.6 mm plus the 2.4 mm the U 307 seat washer adds to reach H1 28 mm, mass 460 g; ratings C 49.4 kN / C0 96.5 kN / Pu 3.55 kN, reference speed 3,200 r/min (thermal) and limiting speed 4,500 r/min (mechanical)." }, { "q": "What does the designation 53307 mean?", "a": "53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 07: bore 35 mm (code 07 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Is the U 307 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53307 and U 307 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." }, { "q": "Is 53307 bidirectional?", "a": "No, the 53-series is single-direction; for reversing thrust with the same self-aligning feature use the 54-series double-direction execution, which needs two U seat washers." } ], "cross_ref": [ { "equiv_sku": "53307", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53307", "53307 + U 307" ], "locale_variants": {} }, { "sku": "53208", "brand": "SKF", "manufacturer_designation": "53208", "series": "53200-series", "type": "thrust_ball", "d_mm": 40, "D_mm": 68, "B_mm": 20.3, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 44.2, "static_load_kN": 96.5, "fatigue_load_limit_kN": 3.6, "reference_speed_rpm": 3600, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53208 is SKF's 40 mm-bore single-direction thrust ball bearing in the 53200 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 40×68×20.3 mm U 208 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 08 encode the bore as 40 mm (code 08 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 40×68×20.3 mm (1.575×2.677×0.799 in), 14.0 mm radial section, C 44.2 kN, C0 96.5 kN, Pu 3.6 kN. Mounted height H1 23 mm includes the U 208 seat washer; the bearing alone is 20.3 mm high. reference speed 3,600 r/min (thermal) and limiting speed 5,300 r/min (mechanical), catalogue mass 350 g. Capacity density: 44.2 kN C from 0.350 kg of bearing steel gives about 126.3 kN per kilogram; static density is correspondingly 275.7 kN/kg at C0 96.5 kN. At the printed limiting speed of 5,300 r/min the mean pitch diameter dm ≈ 54.0 mm implies a dn value around 286k mm·r/min; the 3,600 r/min reference speed is the thermal-planning value under catalogue load. Load balance: C0 96.5 kN against C 44.2 kN gives a 2.18 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 3.6 kN enters the adjusted-life check. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.058 at the 5,300 r/min limiting speed raises the required axial preload to about 4.8 kN; the reference-speed value 2.2 kN is the thermal design point. Static-first selection data: 96.5 kN C0 spread across the 20.3 mm stack gives 4.8 kN of static rating per height millimetre, and the 350 g mass/C0 ratio is about 4 g per static kN — crane-hook and screw positions are normally sized on these two figures. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 68 mm washer can tilt inside the U 208 seat; check the actual tilt allowance in the mounting drawing, since the 2.7 mm washer thickness step does not by itself quantify it.", "applications": [ "vertical pumps with shaft-to-housing misalignment", "crane hooks whose block deflects under offset lifts", "screw-jack spindles that bend under load" ], "failure_modes": [ "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "tilted running after a mismatched U washer leaves only a narrow band of spherical contact", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Replacement orders must list both 53208 and U 208: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 96.5 kN static-rated set.", "Minimum axial load still applies with factor A 0.058: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The shaft washer remains the tight, ground-bore component on the 40 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 208 into the register.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53208 as the single sphered pressed steel execution; other order numbers of the 53208 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 208 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53208?", "a": "53208 measures 40 mm bore × 68 mm OD × 20.3 mm bearing height (1.575 × 2.677 × 0.799 in), or 23 mm mounted H1 including the U 208 seat washer, mass about 350 g. SKF 17000 ratings: C 44.2 kN, C0 96.5 kN, Pu 3.6 kN, reference speed 3,600 r/min (thermal) and limiting speed 5,300 r/min (mechanical)." }, { "q": "What does the designation 53208 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 08 encode the bore as 40 mm (code 08 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." }, { "q": "How much misalignment can 53208 accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." } ], "cross_ref": [ { "equiv_sku": "53208", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53208", "53208 + U 208" ], "locale_variants": {} }, { "sku": "53308", "brand": "SKF", "manufacturer_designation": "53308", "series": "53300-series", "type": "thrust_ball", "d_mm": 40, "D_mm": 78, "B_mm": 28.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 61.8, "static_load_kN": 122, "fatigue_load_limit_kN": 4.5, "reference_speed_rpm": 2800, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 670, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53308 is SKF's 40 mm-bore single-direction thrust ball bearing in the 53300 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 40×78×28.5 mm U 308 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 08 encode the bore as 40 mm (code 08 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 40×78×28.5 mm (1.575×3.071×1.122 in), 19.0 mm radial section, C 61.8 kN, C0 122 kN, Pu 4.5 kN. Mounted height H1 31 mm includes the U 308 seat washer; the bearing alone is 28.5 mm high. reference speed 2,800 r/min (thermal) and limiting speed 4,000 r/min (mechanical), catalogue mass 670 g. Envelope economics: the 28.5 mm axial height over a 19.0 mm radial section yields 2.2 kN of dynamic capacity per height millimetre, and the bearing weighs 670 g for 61.8 kN C — about 11 g per rated kN. Stack/annulus proportions: the 28.5 mm axial stack over the 3,522 mm² washer annulus gives 8.09 mm of height per annular square millimetre ×10⁻³, and at 670 g the bearing holds about 182.1 kN of C0 per kilogram. Load balance: C0 122 kN against C 61.8 kN gives a 1.97 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 4.5 kN enters the adjusted-life check. Capacity density: 61.8 kN C from 0.670 kg of bearing steel gives about 92.2 kN per kilogram; static density is correspondingly 182.1 kN/kg at C0 122 kN. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.077 at the 4,000 r/min limiting speed raises the required axial preload to about 4.3 kN; the reference-speed value 2.1 kN is the thermal design point. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 78 mm washer can tilt inside the U 308 seat; check the actual tilt allowance in the mounting drawing, since the 2.5 mm washer thickness step does not by itself quantify it.", "applications": [ "agricultural and construction-machine pivots", "crane hooks whose block deflects under offset lifts", "machine-tool supports on less rigid fabricated housings" ], "failure_modes": [ "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "fretting corrosion in the spherical interface under oscillation with no grease between washer and seat", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "track rust staining from condensate during long idle periods in humid plant air", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Minimum axial load still applies with factor A 0.077: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 308 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "The 61.8/122 kN figures belong to 53308 specifically (the single sphered pressed steel execution of 53308); suffixed, sphered and counterpart-series order numbers are separate articles, and U 308 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53308?", "a": "53308 measures 40 mm bore × 78 mm OD × 28.5 mm bearing height (1.575 × 3.071 × 1.122 in), or 31 mm mounted H1 including the U 308 seat washer, mass about 670 g. SKF 17000 ratings: C 61.8 kN, C0 122 kN, Pu 4.5 kN, reference speed 2,800 r/min (thermal) and limiting speed 4,000 r/min (mechanical)." }, { "q": "What does the designation 53308 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 08 encode the bore as 40 mm (code 08 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Why does 53308 need a U 308 seat washer?", "a": "The housing washer of 53308 has a sphered back face. The U 308 seat washer presents a matching concave face plus a flat housing face, and without it the convex washer contacts the register at a single point; the pair is what gives the bearing its initial-misalignment capacity." }, { "q": "Is the U 308 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53308 and U 308 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." } ], "cross_ref": [ { "equiv_sku": "53308", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53308", "53308 + U 308" ], "locale_variants": {} }, { "sku": "53408", "brand": "SKF", "manufacturer_designation": "53408", "series": "53400-series", "type": "thrust_ball", "d_mm": 40, "D_mm": 90, "B_mm": 38.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 95.6, "static_load_kN": 183, "fatigue_load_limit_kN": 6.8, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 1350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53408 is SKF's 40 mm-bore single-direction thrust ball bearing in the 53400 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 40×90×38.2 mm U 408 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 08 encode the bore as 40 mm (code 08 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 40×90×38.2 mm (1.575×3.543×1.504 in), 25.0 mm radial section, C 95.6 kN, C0 183 kN, Pu 6.8 kN. Mounted height H1 42 mm includes the U 408 seat washer; the bearing alone is 38.2 mm high. reference speed 2,400 r/min (thermal) and limiting speed 3,200 r/min (mechanical), catalogue mass 1350 g. Imperial cross-check for procurement drawings: 1.575 in bore, 3.543 in OD, 1.504 in height, and the 1350 g catalogue mass converts to 1.350 kg (47.6 oz). Envelope economics: the 38.2 mm axial height over a 25.0 mm radial section yields 2.5 kN of dynamic capacity per height millimetre, and the bearing weighs 1350 g for 95.6 kN C — about 14 g per rated kN. Sizing arithmetic on the 40 mm bore: 95.6 kN C over the 25.0 mm radial section gives 3.8 kN per section millimetre, and the 38.2 mm stack height is 1.53× that section — proportions typical of a 53400 thrust section. Selection figures for 53408: the C0/C ratio is 1.91, Pu 6.8 kN is about 7 % of C, and the catalogue mass works out to roughly 34 g per millimetre of bore; the printed minimum-load factor is A 0.26. Mass and section check: 1350 g inside the 40×90×38.2 mm outline leaves a 25.0 mm radial section, and the 183 kN static rating is 1.91× the dynamic rating — plan static safety and minimum preload against those figures. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53408 and U 408 are two order numbers shipping as two articles; the installed 42 mm H1 rather than 38.2 mm H is the dimension the housing drawing must carry.", "applications": [ "crane hooks whose block deflects under offset lifts", "agricultural and construction-machine pivots", "vertical pumps with shaft-to-housing misalignment" ], "failure_modes": [ "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "corrosion lock of the spherical pair during long outdoor idleness with no preservative grease", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "The sphered housing washer of 53408 MUST run against the U 408 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 408 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "Dimension the housing to the 42 mm mounted height H1 (bearing plus U 408), not the 38.2 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53408 as the single sphered pressed steel execution; other order numbers of the 53408 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 408 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53408?", "a": "53408 measures 40 mm bore × 90 mm OD × 38.2 mm bearing height (1.575 × 3.543 × 1.504 in), or 42 mm mounted H1 including the U 408 seat washer, mass about 1350 g. SKF 17000 ratings: C 95.6 kN, C0 183 kN, Pu 6.8 kN, reference speed 2,400 r/min (thermal) and limiting speed 3,200 r/min (mechanical)." }, { "q": "What does the designation 53408 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 08 encode the bore as 40 mm (code 08 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." }, { "q": "How much misalignment can 53408 accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." } ], "cross_ref": [ { "equiv_sku": "53408", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53408", "53408 + U 408" ], "locale_variants": {} }, { "sku": "53209", "brand": "SKF", "manufacturer_designation": "53209", "series": "53200-series", "type": "thrust_ball", "d_mm": 45, "D_mm": 73, "B_mm": 21.3, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 39, "static_load_kN": 86.5, "fatigue_load_limit_kN": 3.2, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 390, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 53200 series order number 53209 is a SKF single-direction thrust ball bearing for a 45 mm seat, built to ISO 104, with a sphered housing washer paired to a U seat washer, 45×73×21.3 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 09 decodes to 45 mm (code 09 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 45×73×21.3 mm (1.772×2.874×0.839 in), 14.0 mm radial section, C 39 kN, C0 86.5 kN, Pu 3.2 kN. Mounted height H1 24 mm includes the U 209 seat washer; the bearing alone is 21.3 mm high. reference speed 3,400 r/min (thermal) and limiting speed 4,800 r/min (mechanical), catalogue mass 390 g. Mass and section check: 390 g inside the 45×73×21.3 mm outline leaves a 14.0 mm radial section, and the 86.5 kN static rating is 2.22× the dynamic rating — plan static safety and minimum preload against those figures. Capacity density: 39 kN C from 0.390 kg of bearing steel gives about 100.0 kN per kilogram; static density is correspondingly 221.8 kN/kg at C0 86.5 kN. At the printed limiting speed of 4,800 r/min the mean pitch diameter dm ≈ 59.0 mm implies a dn value around 283k mm·r/min; the 3,400 r/min reference speed is the thermal-planning value under catalogue load. Sizing arithmetic on the 45 mm bore: 39 kN C over the 14.0 mm radial section gives 2.8 kN per section millimetre, and the 21.3 mm stack height is 1.52× that section — proportions typical of a 53200 thrust section. Rating split for documentation: dynamic 39 kN (L10 life), static 86.5 kN (safety factor s0), fatigue limit 3.2 kN (adjusted life) — three different uses of three different numbers for 53209, none interchangeable with another. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53209 and U 209 are two order numbers shipping as two articles; the installed 24 mm H1 rather than 21.3 mm H is the dimension the housing drawing must carry.", "applications": [ "machine-tool supports on less rigid fabricated housings", "crane hooks whose block deflects under offset lifts", "vertical pumps with shaft-to-housing misalignment" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "total loss of the aligning function after paint, scale or abrasive dust fills the sphered contact", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "false brinelling of the stationary tracks while the machine stands under vibration", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Replacement orders must list both 53209 and U 209: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 86.5 kN static-rated set.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "Minimum axial load still applies with factor A 0.038: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The 39/86.5 kN figures belong to 53209 specifically (the single sphered pressed steel execution of 53209); suffixed, sphered and counterpart-series order numbers are separate articles, and U 209 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53209?", "a": "Boundary dimensions to ISO 104: bore 45 mm, OD 73 mm, height 21.3 mm (H1 24 mm installed with the U 209 seat washer); weight 390 g. Load figures from SKF 17000: dynamic 39 kN, static 86.5 kN, fatigue limit 3.2 kN; reference speed 3,400 r/min (thermal) and limiting speed 4,800 r/min (mechanical)." }, { "q": "What does the designation 53209 mean?", "a": "the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 09 decodes to 45 mm (code 09 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Is 53209 bidirectional?", "a": "No, the 53-series is single-direction; for reversing thrust with the same self-aligning feature use the 54-series double-direction execution, which needs two U seat washers." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." } ], "cross_ref": [ { "equiv_sku": "53209", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53209", "53209 + U 209" ], "locale_variants": {} }, { "sku": "53309", "brand": "SKF", "manufacturer_designation": "53309", "series": "53300-series", "type": "thrust_ball", "d_mm": 45, "D_mm": 85, "B_mm": 30.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 76.1, "static_load_kN": 153, "fatigue_load_limit_kN": 5.6, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 830, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 53309 is an ISO 104 single-direction thrust ball bearing, 45 mm bore and 85 mm OD, with a sphered housing washer and U seat washer, standing 30.1 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 09: bore 45 mm (code 09 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 45×85×30.1 mm (1.772×3.346×1.185 in), 20.0 mm radial section, C 76.1 kN, C0 153 kN, Pu 5.6 kN. Mounted height H1 33 mm includes the U 309 seat washer; the bearing alone is 30.1 mm high. reference speed 2,600 r/min (thermal) and limiting speed 3,800 r/min (mechanical), catalogue mass 830 g. Light-load floor: Pu = 5.6 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 53309; the number is 7 % of the 76.1 kN dynamic rating. Bore-to-OD planning: OD 85 over bore 45 is a 1.89× step for this size, and the 30.1 mm height gives a bore/height ratio of 1.50; use these ratios when the housing recess around the 45 mm shaft is the first constraint. Pitch-diameter arithmetic: dm = (45+85)/2 = 65.0 mm; at the 3,800 r/min limiting speed that corresponds to roughly 247k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Sizing arithmetic on the 45 mm bore: 76.1 kN C over the 20.0 mm radial section gives 3.8 kN per section millimetre, and the 30.1 mm stack height is 1.51× that section — proportions typical of a 53300 thrust section. Speed-ratio note for this exact unit: the reference speed is 2,600 r/min against a 3,800 r/min limiting speed, a reference-to-limit ratio of 0.68. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 85 mm washer can tilt inside the U 309 seat; check the actual tilt allowance in the mounting drawing, since the 2.9 mm washer thickness step does not by itself quantify it.", "applications": [ "crane hooks whose block deflects under offset lifts", "agricultural and construction-machine pivots", "machine-tool supports on less rigid fabricated housings" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "tilted running after a mismatched U washer leaves only a narrow band of spherical contact", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "washer face scoring from swarf trapped between the loose housing washer and its register" ], "pitfalls": [ "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 309 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Minimum axial load still applies with factor A 0.12: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The 76.1/153 kN figures belong to 53309 specifically (the single sphered pressed steel execution of 53309); suffixed, sphered and counterpart-series order numbers are separate articles, and U 309 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53309?", "a": "The catalogue envelope is 45×85×30.1 mm plus the 2.9 mm the U 309 seat washer adds to reach H1 33 mm, mass 830 g; ratings C 76.1 kN / C0 153 kN / Pu 5.6 kN, reference speed 2,600 r/min (thermal) and limiting speed 3,800 r/min (mechanical)." }, { "q": "What does the designation 53309 mean?", "a": "53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 09: bore 45 mm (code 09 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Is the U 309 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53309 and U 309 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." }, { "q": "Is 53309 bidirectional?", "a": "No, the 53-series is single-direction; for reversing thrust with the same self-aligning feature use the 54-series double-direction execution, which needs two U seat washers." } ], "cross_ref": [ { "equiv_sku": "53309", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53309", "53309 + U 309" ], "locale_variants": {} }, { "sku": "53210", "brand": "SKF", "manufacturer_designation": "53210", "series": "53200-series", "type": "thrust_ball", "d_mm": 50, "D_mm": 78, "B_mm": 23.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 49.4, "static_load_kN": 116, "fatigue_load_limit_kN": 4.3, "reference_speed_rpm": 3200, "limiting_speed_rpm": 4500, "max_rpm": 4500, "weight_g": 470, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53210 is SKF's 50 mm-bore single-direction thrust ball bearing in the 53200 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 50×78×23.5 mm U 210 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 10 encode the bore as 50 mm (code 10 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 50×78×23.5 mm (1.969×3.071×0.925 in), 14.0 mm radial section, C 49.4 kN, C0 116 kN, Pu 4.3 kN. Mounted height H1 26 mm includes the U 210 seat washer; the bearing alone is 23.5 mm high. reference speed 3,200 r/min (thermal) and limiting speed 4,500 r/min (mechanical), catalogue mass 470 g. Speed-ratio note for this exact unit: the reference speed is 3,200 r/min against a 4,500 r/min limiting speed, a reference-to-limit ratio of 0.71. Stack/annulus proportions: the 23.5 mm axial stack over the 2,815 mm² washer annulus gives 8.35 mm of height per annular square millimetre ×10⁻³, and at 470 g the bearing holds about 246.8 kN of C0 per kilogram. Capacity density: 49.4 kN C from 0.470 kg of bearing steel gives about 105.1 kN per kilogram; static density is correspondingly 246.8 kN/kg at C0 116 kN. Rating split for documentation: dynamic 49.4 kN (L10 life), static 116 kN (safety factor s0), fatigue limit 4.3 kN (adjusted life) — three different uses of three different numbers for 53210, none interchangeable with another. Selection figures for 53210: the C0/C ratio is 2.35, Pu 4.3 kN is about 9 % of C, and the catalogue mass works out to roughly 9 g per millimetre of bore; the printed minimum-load factor is A 0.069. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 78 mm washer can tilt inside the U 210 seat; check the actual tilt allowance in the mounting drawing, since the 2.5 mm washer thickness step does not by itself quantify it.", "applications": [ "crane hooks whose block deflects under offset lifts", "screw-jack spindles that bend under load", "vertical pumps with shaft-to-housing misalignment" ], "failure_modes": [ "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "edge loading on the ball set when the U seat washer is fitted with its concave face reversed", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "The sphered housing washer of 53210 MUST run against the U 210 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 210 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53210 as the single sphered pressed steel execution; other order numbers of the 53210 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 210 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53210?", "a": "53210 measures 50 mm bore × 78 mm OD × 23.5 mm bearing height (1.969 × 3.071 × 0.925 in), or 26 mm mounted H1 including the U 210 seat washer, mass about 470 g. SKF 17000 ratings: C 49.4 kN, C0 116 kN, Pu 4.3 kN, reference speed 3,200 r/min (thermal) and limiting speed 4,500 r/min (mechanical)." }, { "q": "What does the designation 53210 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 10 encode the bore as 50 mm (code 10 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Why does 53210 need a U 210 seat washer?", "a": "The housing washer of 53210 has a sphered back face. The U 210 seat washer presents a matching concave face plus a flat housing face, and without it the convex washer contacts the register at a single point; the pair is what gives the bearing its initial-misalignment capacity." }, { "q": "Is the U 210 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53210 and U 210 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." } ], "cross_ref": [ { "equiv_sku": "53210", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53210", "53210 + U 210" ], "locale_variants": {} }, { "sku": "53310", "brand": "SKF", "manufacturer_designation": "53310", "series": "53300-series", "type": "thrust_ball", "d_mm": 50, "D_mm": 95, "B_mm": 34.3, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 81.9, "static_load_kN": 170, "fatigue_load_limit_kN": 6.3, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 53310 is an ISO 104 single-direction thrust ball bearing, 50 mm bore and 95 mm OD, with a sphered housing washer and U seat washer, standing 34.3 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 10: bore 50 mm (code 10 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 50×95×34.3 mm (1.969×3.74×1.35 in), 22.5 mm radial section, C 81.9 kN, C0 170 kN, Pu 6.3 kN. Mounted height H1 37 mm includes the U 310 seat washer; the bearing alone is 34.3 mm high. reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical), catalogue mass 1200 g. Imperial cross-check for procurement drawings: 1.969 in bore, 3.74 in OD, 1.35 in height, and the 1200 g catalogue mass converts to 1.200 kg (42.3 oz). Envelope economics: the 34.3 mm axial height over a 22.5 mm radial section yields 2.4 kN of dynamic capacity per height millimetre, and the bearing weighs 1200 g for 81.9 kN C — about 15 g per rated kN. Bore-to-OD planning: OD 95 over bore 50 is a 1.90× step for this size, and the 34.3 mm height gives a bore/height ratio of 1.46; use these ratios when the housing recess around the 50 mm shaft is the first constraint. Minimum-load arithmetic: with dm ≈ 72.5 mm and factor A 0.19, Fam ≈ A·(n·dm/1000)² at the 2,400 r/min reference speed is about 5.8 kN for 53310; below that preload the balls skid and smear the tracks. Light-load floor: Pu = 6.3 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 53310; the number is 8 % of the 81.9 kN dynamic rating. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53310 and U 310 are two order numbers shipping as two articles; the installed 37 mm H1 rather than 34.3 mm H is the dimension the housing drawing must carry.", "applications": [ "crane hooks whose block deflects under offset lifts", "machine-tool supports on less rigid fabricated housings", "agricultural and construction-machine pivots" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "corrosion lock of the spherical pair during long outdoor idleness with no preservative grease", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "The sphered housing washer of 53310 MUST run against the U 310 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 310 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "Dimension the housing to the 37 mm mounted height H1 (bearing plus U 310), not the 34.3 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53310 as the single sphered pressed steel execution; other order numbers of the 53310 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 310 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53310?", "a": "The catalogue envelope is 50×95×34.3 mm plus the 2.7 mm the U 310 seat washer adds to reach H1 37 mm, mass 1200 g; ratings C 81.9 kN / C0 170 kN / Pu 6.3 kN, reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical)." }, { "q": "What does the designation 53310 mean?", "a": "53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 10: bore 50 mm (code 10 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Is the U 310 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53310 and U 310 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." }, { "q": "Is 53310 bidirectional?", "a": "No, the 53-series is single-direction; for reversing thrust with the same self-aligning feature use the 54-series double-direction execution, which needs two U seat washers." } ], "cross_ref": [ { "equiv_sku": "53310", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53310", "53310 + U 310" ], "locale_variants": {} }, { "sku": "53410", "brand": "SKF", "manufacturer_designation": "53410", "series": "53400-series", "type": "thrust_ball", "d_mm": 50, "D_mm": 110, "B_mm": 45.6, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 159, "static_load_kN": 340, "fatigue_load_limit_kN": 12.5, "reference_speed_rpm": 1900, "limiting_speed_rpm": 2600, "max_rpm": 2600, "weight_g": 2300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53410 is SKF's 50 mm-bore single-direction thrust ball bearing in the 53400 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 50×110×45.6 mm U 410 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 10 encode the bore as 50 mm (code 10 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 50×110×45.6 mm (1.969×4.331×1.795 in), 30.0 mm radial section, C 159 kN, C0 340 kN, Pu 12.5 kN. Mounted height H1 50 mm includes the U 410 seat washer; the bearing alone is 45.6 mm high. reference speed 1,900 r/min (thermal) and limiting speed 2,600 r/min (mechanical), catalogue mass 2300 g. Light-load floor: Pu = 12.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 53410; the number is 8 % of the 159 kN dynamic rating. Pitch-diameter arithmetic: dm = (50+110)/2 = 80.0 mm; at the 2,600 r/min limiting speed that corresponds to roughly 208k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Bore-to-OD planning: OD 110 over bore 50 is a 2.20× step for this size, and the 45.6 mm height gives a bore/height ratio of 1.10; use these ratios when the housing recess around the 50 mm shaft is the first constraint. Load balance: C0 340 kN against C 159 kN gives a 2.14 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 12.5 kN enters the adjusted-life check. Sizing arithmetic on the 50 mm bore: 159 kN C over the 30.0 mm radial section gives 5.3 kN per section millimetre, and the 45.6 mm stack height is 1.52× that section — proportions typical of a 53400 thrust section. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53410 and U 410 are two order numbers shipping as two articles; the installed 50 mm H1 rather than 45.6 mm H is the dimension the housing drawing must carry.", "applications": [ "agricultural and construction-machine pivots", "screw-jack spindles that bend under load", "crane hooks whose block deflects under offset lifts" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "total loss of the aligning function after paint, scale or abrasive dust fills the sphered contact", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Dimension the housing to the 50 mm mounted height H1 (bearing plus U 410), not the 45.6 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "The sphered housing washer of 53410 MUST run against the U 410 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53410 as the single sphered pressed steel execution; other order numbers of the 53410 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 410 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53410?", "a": "53410 measures 50 mm bore × 110 mm OD × 45.6 mm bearing height (1.969 × 4.331 × 1.795 in), or 50 mm mounted H1 including the U 410 seat washer, mass about 2300 g. SKF 17000 ratings: C 159 kN, C0 340 kN, Pu 12.5 kN, reference speed 1,900 r/min (thermal) and limiting speed 2,600 r/min (mechanical)." }, { "q": "What does the designation 53410 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 10 encode the bore as 50 mm (code 10 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Why does 53410 need a U 410 seat washer?", "a": "The housing washer of 53410 has a sphered back face. The U 410 seat washer presents a matching concave face plus a flat housing face, and without it the convex washer contacts the register at a single point; the pair is what gives the bearing its initial-misalignment capacity." }, { "q": "Is the U 410 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53410 and U 410 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." } ], "cross_ref": [ { "equiv_sku": "53410", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53410", "53410 + U 410" ], "locale_variants": {} }, { "sku": "53211", "brand": "SKF", "manufacturer_designation": "53211", "series": "53200-series", "type": "thrust_ball", "d_mm": 55, "D_mm": 90, "B_mm": 27.3, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 58.5, "static_load_kN": 134, "fatigue_load_limit_kN": 4.9, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53211 is SKF's 55 mm-bore single-direction thrust ball bearing in the 53200 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 55×90×27.3 mm U 211 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 11 encode the bore as 55 mm (code 11 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 55×90×27.3 mm (2.165×3.543×1.075 in), 17.5 mm radial section, C 58.5 kN, C0 134 kN, Pu 4.9 kN. Mounted height H1 30 mm includes the U 211 seat washer; the bearing alone is 27.3 mm high. reference speed 2,800 r/min (thermal) and limiting speed 3,800 r/min (mechanical), catalogue mass 750 g. Speed band width for this size is 1,000 r/min between reference and limiting (1.36× ratio); lubrication, preload and heat removal decide where inside that band 53211 can actually run. Static-first selection data: 134 kN C0 spread across the 27.3 mm stack gives 4.9 kN of static rating per height millimetre, and the 750 g mass/C0 ratio is about 6 g per static kN — crane-hook and screw positions are normally sized on these two figures. Rating split for documentation: dynamic 58.5 kN (L10 life), static 134 kN (safety factor s0), fatigue limit 4.9 kN (adjusted life) — three different uses of three different numbers for 53211, none interchangeable with another. Minimum-load arithmetic: with dm ≈ 72.5 mm and factor A 0.11, Fam ≈ A·(n·dm/1000)² at the 2,800 r/min reference speed is about 4.5 kN for 53211; below that preload the balls skid and smear the tracks. Envelope economics: the 27.3 mm axial height over a 17.5 mm radial section yields 2.1 kN of dynamic capacity per height millimetre, and the bearing weighs 750 g for 58.5 kN C — about 13 g per rated kN. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 90 mm washer can tilt inside the U 211 seat; check the actual tilt allowance in the mounting drawing, since the 2.7 mm washer thickness step does not by itself quantify it.", "applications": [ "machine-tool supports on less rigid fabricated housings", "vertical pumps with shaft-to-housing misalignment", "screw-jack spindles that bend under load" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "pitting on one track sector from a perpetually eccentric thrust line", "total loss of the aligning function after paint, scale or abrasive dust fills the sphered contact", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Dimension the housing to the 30 mm mounted height H1 (bearing plus U 211), not the 27.3 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "The sphered housing washer of 53211 MUST run against the U 211 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "The shaft washer remains the tight, ground-bore component on the 55 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 211 into the register.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Ordering discipline for 53211: the catalogue page quotes 53211 plus U 211 and its 58.5/134 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53211?", "a": "53211 measures 55 mm bore × 90 mm OD × 27.3 mm bearing height (2.165 × 3.543 × 1.075 in), or 30 mm mounted H1 including the U 211 seat washer, mass about 750 g. SKF 17000 ratings: C 58.5 kN, C0 134 kN, Pu 4.9 kN, reference speed 2,800 r/min (thermal) and limiting speed 3,800 r/min (mechanical)." }, { "q": "What does the designation 53211 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 11 encode the bore as 55 mm (code 11 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." }, { "q": "How much misalignment can 53211 accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." } ], "cross_ref": [ { "equiv_sku": "53211", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53211", "53211 + U 211" ], "locale_variants": {} }, { "sku": "53311", "brand": "SKF", "manufacturer_designation": "53311", "series": "53300-series", "type": "thrust_ball", "d_mm": 55, "D_mm": 105, "B_mm": 39.3, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 101, "static_load_kN": 224, "fatigue_load_limit_kN": 8.3, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 53300 series order number 53311 is a SKF single-direction thrust ball bearing for a 55 mm seat, built to ISO 104, with a sphered housing washer paired to a U seat washer, 55×105×39.3 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 11 decodes to 55 mm (code 11 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 55×105×39.3 mm (2.165×4.134×1.547 in), 25.0 mm radial section, C 101 kN, C0 224 kN, Pu 8.3 kN. Mounted height H1 42 mm includes the U 311 seat washer; the bearing alone is 39.3 mm high. reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical), catalogue mass 1700 g. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 3,000 r/min while thermal balance under catalogue load sets the 2,200 r/min reference; at dm ≈ 80.0 mm the corresponding dn is approximately 240k mm·r/min. Load balance: C0 224 kN against C 101 kN gives a 2.22 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 8.3 kN enters the adjusted-life check. Sizing arithmetic on the 55 mm bore: 101 kN C over the 25.0 mm radial section gives 4.0 kN per section millimetre, and the 39.3 mm stack height is 1.57× that section — proportions typical of a 53300 thrust section. Light-load floor: Pu = 8.3 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 53311; the number is 8 % of the 101 kN dynamic rating. Mass and section check: 1700 g inside the 55×105×39.3 mm outline leaves a 25.0 mm radial section, and the 224 kN static rating is 2.22× the dynamic rating — plan static safety and minimum preload against those figures. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 105 mm washer can tilt inside the U 311 seat; check the actual tilt allowance in the mounting drawing, since the 2.7 mm washer thickness step does not by itself quantify it.", "applications": [ "vertical pumps with shaft-to-housing misalignment", "screw-jack spindles that bend under load", "crane hooks whose block deflects under offset lifts" ], "failure_modes": [ "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "cage damage from mounting force applied through the balls instead of the washer face", "edge loading on the ball set when the U seat washer is fitted with its concave face reversed", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Minimum axial load still applies with factor A 0.26: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 311 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "The 101/224 kN figures belong to 53311 specifically (the single sphered pressed steel execution of 53311); suffixed, sphered and counterpart-series order numbers are separate articles, and U 311 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53311?", "a": "Boundary dimensions to ISO 104: bore 55 mm, OD 105 mm, height 39.3 mm (H1 42 mm installed with the U 311 seat washer); weight 1700 g. Load figures from SKF 17000: dynamic 101 kN, static 224 kN, fatigue limit 8.3 kN; reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical)." }, { "q": "What does the designation 53311 mean?", "a": "the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 11 decodes to 55 mm (code 11 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Is 53311 bidirectional?", "a": "No, the 53-series is single-direction; for reversing thrust with the same self-aligning feature use the 54-series double-direction execution, which needs two U seat washers." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." } ], "cross_ref": [ { "equiv_sku": "53311", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53311", "53311 + U 311" ], "locale_variants": {} }, { "sku": "53411", "brand": "SKF", "manufacturer_designation": "53411", "series": "53400-series", "type": "thrust_ball", "d_mm": 55, "D_mm": 120, "B_mm": 50.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 195, "static_load_kN": 400, "fatigue_load_limit_kN": 14.6, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 3100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53411 is SKF's 55 mm-bore single-direction thrust ball bearing in the 53400 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 55×120×50.5 mm U 411 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 11 encode the bore as 55 mm (code 11 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 55×120×50.5 mm (2.165×4.724×1.988 in), 32.5 mm radial section, C 195 kN, C0 400 kN, Pu 14.6 kN. Mounted height H1 55 mm includes the U 411 seat washer; the bearing alone is 50.5 mm high. reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical), catalogue mass 3100 g. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 2,400 r/min while thermal balance under catalogue load sets the 1,700 r/min reference; at dm ≈ 87.5 mm the corresponding dn is approximately 210k mm·r/min. Bore-to-OD planning: OD 120 over bore 55 is a 2.18× step for this size, and the 50.5 mm height gives a bore/height ratio of 1.09; use these ratios when the housing recess around the 55 mm shaft is the first constraint. Track-circle loading: per millimetre of mean track circumference the 195 kN dynamic rating corresponds to roughly 0.71 kN/mm of π·dm track, a useful comparison against the other dimension series of the 55 mm bore. Pitch-diameter arithmetic: dm = (55+120)/2 = 87.5 mm; at the 2,400 r/min limiting speed that corresponds to roughly 210k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Washer-annulus check: the π/4·(D²−d²) contact annulus of 53411 covers about 8,934 mm², distributing C0 400 kN over a mean track circle of π·dm ≈ 275 mm. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53411 and U 411 are two order numbers shipping as two articles; the installed 55 mm H1 rather than 50.5 mm H is the dimension the housing drawing must carry.", "applications": [ "screw-jack spindles that bend under load", "machine-tool supports on less rigid fabricated housings", "crane hooks whose block deflects under offset lifts" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "pitting on one track sector from a perpetually eccentric thrust line", "fretting corrosion in the spherical interface under oscillation with no grease between washer and seat", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Minimum axial load still applies with factor A 0.79: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 411 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "The 195/400 kN figures belong to 53411 specifically (the single sphered pressed steel execution of 53411); suffixed, sphered and counterpart-series order numbers are separate articles, and U 411 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53411?", "a": "53411 measures 55 mm bore × 120 mm OD × 50.5 mm bearing height (2.165 × 4.724 × 1.988 in), or 55 mm mounted H1 including the U 411 seat washer, mass about 3100 g. SKF 17000 ratings: C 195 kN, C0 400 kN, Pu 14.6 kN, reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical)." }, { "q": "What does the designation 53411 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 11 encode the bore as 55 mm (code 11 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." }, { "q": "How much misalignment can 53411 accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." } ], "cross_ref": [ { "equiv_sku": "53411", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53411", "53411 + U 411" ], "locale_variants": {} }, { "sku": "53212", "brand": "SKF", "manufacturer_designation": "53212", "series": "53200-series", "type": "thrust_ball", "d_mm": 60, "D_mm": 95, "B_mm": 28, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 59.2, "static_load_kN": 140, "fatigue_load_limit_kN": 5.1, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 820, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53212 is SKF's 60 mm-bore single-direction thrust ball bearing in the 53200 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 60×95×28 mm U 212 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 12 encode the bore as 60 mm (code 12 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 60×95×28 mm (2.362×3.74×1.102 in), 17.5 mm radial section, C 59.2 kN, C0 140 kN, Pu 5.1 kN. Mounted height H1 31 mm includes the U 212 seat washer; the bearing alone is 28 mm high. reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical), catalogue mass 820 g. Sizing arithmetic on the 60 mm bore: 59.2 kN C over the 17.5 mm radial section gives 3.4 kN per section millimetre, and the 28 mm stack height is 1.60× that section — proportions typical of a 53200 thrust section. Imperial cross-check for procurement drawings: 2.362 in bore, 3.74 in OD, 1.102 in height, and the 820 g catalogue mass converts to 0.820 kg (28.9 oz). Mass and section check: 820 g inside the 60×95×28 mm outline leaves a 17.5 mm radial section, and the 140 kN static rating is 2.36× the dynamic rating — plan static safety and minimum preload against those figures. Rating split for documentation: dynamic 59.2 kN (L10 life), static 140 kN (safety factor s0), fatigue limit 5.1 kN (adjusted life) — three different uses of three different numbers for 53212, none interchangeable with another. Selection figures for 53212: the C0/C ratio is 2.36, Pu 5.1 kN is about 9 % of C, and the catalogue mass works out to roughly 14 g per millimetre of bore; the printed minimum-load factor is A 0.12. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53212 and U 212 are two order numbers shipping as two articles; the installed 31 mm H1 rather than 28 mm H is the dimension the housing drawing must carry.", "applications": [ "large screw jacks on elastic frames", "heavy hook blocks and lifting equipment", "winch drums on fabricated structures" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "point-contact destruction of the housing register when a sphered washer is operated directly on a flat face without its U seat washer", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "false brinelling of the stationary tracks while the machine stands under vibration", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 212 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "Minimum axial load still applies with factor A 0.12: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "Dimension the housing to the 31 mm mounted height H1 (bearing plus U 212), not the 28 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "Ordering discipline for 53212: the catalogue page quotes 53212 plus U 212 and its 59.2/140 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53212?", "a": "53212 measures 60 mm bore × 95 mm OD × 28 mm bearing height (2.362 × 3.74 × 1.102 in), or 31 mm mounted H1 including the U 212 seat washer, mass about 820 g. SKF 17000 ratings: C 59.2 kN, C0 140 kN, Pu 5.1 kN, reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical)." }, { "q": "What does the designation 53212 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 12 encode the bore as 60 mm (code 12 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Why does 53212 need a U 212 seat washer?", "a": "The housing washer of 53212 has a sphered back face. The U 212 seat washer presents a matching concave face plus a flat housing face, and without it the convex washer contacts the register at a single point; the pair is what gives the bearing its initial-misalignment capacity." }, { "q": "Is the U 212 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53212 and U 212 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." } ], "cross_ref": [ { "equiv_sku": "53212", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53212", "53212 + U 212" ], "locale_variants": {} }, { "sku": "53312", "brand": "SKF", "manufacturer_designation": "53312", "series": "53300-series", "type": "thrust_ball", "d_mm": 60, "D_mm": 110, "B_mm": 38.3, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 101, "static_load_kN": 224, "fatigue_load_limit_kN": 8.3, "reference_speed_rpm": 2000, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53312 is SKF's 60 mm-bore single-direction thrust ball bearing in the 53300 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 60×110×38.3 mm U 312 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 12 encode the bore as 60 mm (code 12 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 60×110×38.3 mm (2.362×4.331×1.508 in), 25.0 mm radial section, C 101 kN, C0 224 kN, Pu 8.3 kN. Mounted height H1 42 mm includes the U 312 seat washer; the bearing alone is 38.3 mm high. reference speed 2,000 r/min (thermal) and limiting speed 3,000 r/min (mechanical), catalogue mass 1700 g. Track-circle loading: per millimetre of mean track circumference the 101 kN dynamic rating corresponds to roughly 0.38 kN/mm of π·dm track, a useful comparison against the other dimension series of the 60 mm bore. Selection figures for 53312: the C0/C ratio is 2.22, Pu 8.3 kN is about 8 % of C, and the catalogue mass works out to roughly 28 g per millimetre of bore; the printed minimum-load factor is A 0.26. Imperial cross-check for procurement drawings: 2.362 in bore, 4.331 in OD, 1.508 in height, and the 1700 g catalogue mass converts to 1.700 kg (60.0 oz). Capacity density: 101 kN C from 1.700 kg of bearing steel gives about 59.4 kN per kilogram; static density is correspondingly 131.8 kN/kg at C0 224 kN. Rating split for documentation: dynamic 101 kN (L10 life), static 224 kN (safety factor s0), fatigue limit 8.3 kN (adjusted life) — three different uses of three different numbers for 53312, none interchangeable with another. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53312 and U 312 are two order numbers shipping as two articles; the installed 42 mm H1 rather than 38.3 mm H is the dimension the housing drawing must carry.", "applications": [ "vertical process pumps on welded housings", "marine deck-machinery pivots", "winch drums on fabricated structures" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "edge loading on the ball set when the U seat washer is fitted with its concave face reversed", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "false brinelling of the stationary tracks while the machine stands under vibration" ], "pitfalls": [ "Replacement orders must list both 53312 and U 312: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 224 kN static-rated set.", "Dimension the housing to the 42 mm mounted height H1 (bearing plus U 312), not the 38.3 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 312 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "The shaft washer remains the tight, ground-bore component on the 60 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 312 into the register.", "The 101/224 kN figures belong to 53312 specifically (the single sphered pressed steel execution of 53312); suffixed, sphered and counterpart-series order numbers are separate articles, and U 312 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53312?", "a": "53312 measures 60 mm bore × 110 mm OD × 38.3 mm bearing height (2.362 × 4.331 × 1.508 in), or 42 mm mounted H1 including the U 312 seat washer, mass about 1700 g. SKF 17000 ratings: C 101 kN, C0 224 kN, Pu 8.3 kN, reference speed 2,000 r/min (thermal) and limiting speed 3,000 r/min (mechanical)." }, { "q": "What does the designation 53312 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 12 encode the bore as 60 mm (code 12 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." }, { "q": "How much misalignment can 53312 accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." } ], "cross_ref": [ { "equiv_sku": "53312", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53312", "53312 + U 312" ], "locale_variants": {} }, { "sku": "53412-M", "brand": "SKF", "manufacturer_designation": "53412 M", "series": "53400-series", "type": "thrust_ball", "d_mm": 60, "D_mm": 130, "B_mm": 54, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 199, "static_load_kN": 430, "fatigue_load_limit_kN": 16, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 3800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53412 M is SKF's 60 mm-bore single-direction thrust ball bearing in the 53400 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 60×130×54 mm U 412 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 12 encode the bore as 60 mm (code 12 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 60×130×54 mm (2.362×5.118×2.126 in), 35.0 mm radial section, C 199 kN, C0 430 kN, Pu 16 kN. Mounted height H1 58 mm includes the U 412 seat washer; the bearing alone is 54 mm high. reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical), catalogue mass 3800 g. Speed planning separates the two ceilings mechanically: the pressed brass cage and balls tolerate 2,200 r/min while thermal balance under catalogue load sets the 1,600 r/min reference; at dm ≈ 95.0 mm the corresponding dn is approximately 209k mm·r/min. Speed-ratio note for this exact unit: the reference speed is 1,600 r/min against a 2,200 r/min limiting speed, a reference-to-limit ratio of 0.73. Track-circle loading: per millimetre of mean track circumference the 199 kN dynamic rating corresponds to roughly 0.67 kN/mm of π·dm track, a useful comparison against the other dimension series of the 60 mm bore. Minimum-load arithmetic: with dm ≈ 95.0 mm and factor A 0.96, Fam ≈ A·(n·dm/1000)² at the 1,600 r/min reference speed is about 22.2 kN for 53412 M; below that preload the balls skid and smear the tracks. Washer-stack proportions: the U 412 seat washer adds 4.0 mm to the 54 mm bearing height for a mounted H1 of 58 mm, while the 35.0 mm radial section against 60 mm bore (section/bore ≈ 0.58) identifies the envelope. Heavy sphered-execution note: this M order number combines the machined brass ball-centred cage with the sphered housing washer and its U seat washer; it is the large-bore answer for hook blocks and pivots whose fabricated structure deflects — verify the spherical pair swivels freely under a light preload before the working load goes on. The M brass-cage option at 60 mm bore pairs the heavy-section cage with the U 412 seat requirement — order all three articles (bearing + U washer + appropriate lubricant) together, and log the H1 58 mm installed dimension on the maintenance card.", "applications": [ "heavy hook blocks and lifting equipment", "marine deck-machinery pivots", "vertical process pumps on welded housings" ], "failure_modes": [ "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "corrosion lock of the spherical pair during long outdoor idleness with no preservative grease", "fretting between the sphered washer and U seat washer when the spherical interface runs dry under oscillation", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "The shaft washer remains the tight, ground-bore component on the 60 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 412 into the register.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Replacement orders must list both 53412 M and U 412: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 430 kN static-rated set.", "Ordering discipline for 53412: the catalogue page quotes 53412 M plus U 412 and its 199/430 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53412-M?", "a": "53412 M measures 60 mm bore × 130 mm OD × 54 mm bearing height (2.362 × 5.118 × 2.126 in), or 58 mm mounted H1 including the U 412 seat washer, mass about 3800 g. SKF 17000 ratings: C 199 kN, C0 430 kN, Pu 16 kN, reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical)." }, { "q": "What does the designation 53412 M mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 12 encode the bore as 60 mm (code 12 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." }, { "q": "How much misalignment can 53412-M accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." } ], "cross_ref": [ { "equiv_sku": "53412", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53412-M", "53412 M", "53412 M + U 412" ], "locale_variants": {} }, { "sku": "53213", "brand": "SKF", "manufacturer_designation": "53213", "series": "53200-series", "type": "thrust_ball", "d_mm": 65, "D_mm": 100, "B_mm": 28.7, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 60.5, "static_load_kN": 150, "fatigue_load_limit_kN": 5.5, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 910, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 53213 is an ISO 104 single-direction thrust ball bearing, 65 mm bore and 100 mm OD, with a sphered housing washer and U seat washer, standing 28.7 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 13: bore 65 mm (code 13 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 65×100×28.7 mm (2.559×3.937×1.13 in), 17.5 mm radial section, C 60.5 kN, C0 150 kN, Pu 5.5 kN. Mounted height H1 32 mm includes the U 213 seat washer; the bearing alone is 28.7 mm high. reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical), catalogue mass 910 g. Minimum-load arithmetic: with dm ≈ 82.5 mm and factor A 0.14, Fam ≈ A·(n·dm/1000)² at the 2,600 r/min reference speed is about 6.4 kN for 53213; below that preload the balls skid and smear the tracks. Bore-to-OD planning: OD 100 over bore 65 is a 1.54× step for this size, and the 28.7 mm height gives a bore/height ratio of 2.26; use these ratios when the housing recess around the 65 mm shaft is the first constraint. Capacity density: 60.5 kN C from 0.910 kg of bearing steel gives about 66.5 kN per kilogram; static density is correspondingly 164.8 kN/kg at C0 150 kN. Load balance: C0 150 kN against C 60.5 kN gives a 2.48 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 5.5 kN enters the adjusted-life check. Stack/annulus proportions: the 28.7 mm axial stack over the 4,536 mm² washer annulus gives 6.33 mm of height per annular square millimetre ×10⁻³, and at 910 g the bearing holds about 164.8 kN of C0 per kilogram. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 100 mm washer can tilt inside the U 213 seat; check the actual tilt allowance in the mounting drawing, since the 3.3 mm washer thickness step does not by itself quantify it.", "applications": [ "heavy hook blocks and lifting equipment", "winch drums on fabricated structures", "marine deck-machinery pivots" ], "failure_modes": [ "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "pitting on one track sector from a perpetually eccentric thrust line", "total loss of the aligning function after paint, scale or abrasive dust fills the sphered contact", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "The shaft washer remains the tight, ground-bore component on the 65 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 213 into the register.", "Minimum axial load still applies with factor A 0.14: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "The sphered housing washer of 53213 MUST run against the U 213 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53213 as the single sphered pressed steel execution; other order numbers of the 53213 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 213 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53213?", "a": "The catalogue envelope is 65×100×28.7 mm plus the 3.3 mm the U 213 seat washer adds to reach H1 32 mm, mass 910 g; ratings C 60.5 kN / C0 150 kN / Pu 5.5 kN, reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical)." }, { "q": "What does the designation 53213 mean?", "a": "53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 13: bore 65 mm (code 13 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Is the U 213 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53213 and U 213 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." }, { "q": "Is 53213 bidirectional?", "a": "No, the 53-series is single-direction; for reversing thrust with the same self-aligning feature use the 54-series double-direction execution, which needs two U seat washers." } ], "cross_ref": [ { "equiv_sku": "53213", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53213", "53213 + U 213" ], "locale_variants": {} }, { "sku": "53313", "brand": "SKF", "manufacturer_designation": "53313", "series": "53300-series", "type": "thrust_ball", "d_mm": 65, "D_mm": 115, "B_mm": 39.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 106, "static_load_kN": 240, "fatigue_load_limit_kN": 8.8, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 1900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 53300 series order number 53313 is a SKF single-direction thrust ball bearing for a 65 mm seat, built to ISO 104, with a sphered housing washer paired to a U seat washer, 65×115×39.4 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 13 decodes to 65 mm (code 13 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 65×115×39.4 mm (2.559×4.528×1.551 in), 25.0 mm radial section, C 106 kN, C0 240 kN, Pu 8.8 kN. Mounted height H1 43 mm includes the U 313 seat washer; the bearing alone is 39.4 mm high. reference speed 2,000 r/min (thermal) and limiting speed 2,800 r/min (mechanical), catalogue mass 1900 g. Sizing arithmetic on the 65 mm bore: 106 kN C over the 25.0 mm radial section gives 4.2 kN per section millimetre, and the 39.4 mm stack height is 1.58× that section — proportions typical of a 53300 thrust section. Stack/annulus proportions: the 39.4 mm axial stack over the 7,069 mm² washer annulus gives 5.57 mm of height per annular square millimetre ×10⁻³, and at 1900 g the bearing holds about 126.3 kN of C0 per kilogram. Imperial cross-check for procurement drawings: 2.559 in bore, 4.528 in OD, 1.551 in height, and the 1900 g catalogue mass converts to 1.900 kg (67.0 oz). Minimum-load arithmetic: with dm ≈ 90.0 mm and factor A 0.3, Fam ≈ A·(n·dm/1000)² at the 2,000 r/min reference speed is about 9.7 kN for 53313; below that preload the balls skid and smear the tracks. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 2,800 r/min while thermal balance under catalogue load sets the 2,000 r/min reference; at dm ≈ 90.0 mm the corresponding dn is approximately 252k mm·r/min. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53313 and U 313 are two order numbers shipping as two articles; the installed 43 mm H1 rather than 39.4 mm H is the dimension the housing drawing must carry.", "applications": [ "large screw jacks on elastic frames", "marine deck-machinery pivots", "vertical process pumps on welded housings" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "tilted running after a mismatched U washer leaves only a narrow band of spherical contact", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "The shaft washer remains the tight, ground-bore component on the 65 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 313 into the register.", "Minimum axial load still applies with factor A 0.3: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "Replacement orders must list both 53313 and U 313: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 240 kN static-rated set.", "The sphered housing washer of 53313 MUST run against the U 313 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53313 as the single sphered pressed steel execution; other order numbers of the 53313 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 313 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53313?", "a": "Boundary dimensions to ISO 104: bore 65 mm, OD 115 mm, height 39.4 mm (H1 43 mm installed with the U 313 seat washer); weight 1900 g. Load figures from SKF 17000: dynamic 106 kN, static 240 kN, fatigue limit 8.8 kN; reference speed 2,000 r/min (thermal) and limiting speed 2,800 r/min (mechanical)." }, { "q": "What does the designation 53313 mean?", "a": "the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 13 decodes to 65 mm (code 13 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Is 53313 bidirectional?", "a": "No, the 53-series is single-direction; for reversing thrust with the same self-aligning feature use the 54-series double-direction execution, which needs two U seat washers." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." } ], "cross_ref": [ { "equiv_sku": "53313", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53313", "53313 + U 313" ], "locale_variants": {} }, { "sku": "53214", "brand": "SKF", "manufacturer_designation": "53214", "series": "53200-series", "type": "thrust_ball", "d_mm": 70, "D_mm": 105, "B_mm": 27, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 62.4, "static_load_kN": 160, "fatigue_load_limit_kN": 5.85, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 970, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53214 is SKF's 70 mm-bore single-direction thrust ball bearing in the 53200 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 70×105×27 mm U 214 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 14 encode the bore as 70 mm (code 14 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 70×105×27 mm (2.756×4.134×1.063 in), 17.5 mm radial section, C 62.4 kN, C0 160 kN, Pu 5.85 kN. Mounted height H1 32 mm includes the U 214 seat washer; the bearing alone is 27 mm high. reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical), catalogue mass 970 g. Pitch-diameter arithmetic: dm = (70+105)/2 = 87.5 mm; at the 3,600 r/min limiting speed that corresponds to roughly 315k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Selection figures for 53214: the C0/C ratio is 2.56, Pu 5.85 kN is about 9 % of C, and the catalogue mass works out to roughly 14 g per millimetre of bore; the printed minimum-load factor is A 0.16. Capacity density: 62.4 kN C from 0.970 kg of bearing steel gives about 64.3 kN per kilogram; static density is correspondingly 164.9 kN/kg at C0 160 kN. Speed band width for this size is 1,000 r/min between reference and limiting (1.38× ratio); lubrication, preload and heat removal decide where inside that band 53214 can actually run. Envelope economics: the 27 mm axial height over a 17.5 mm radial section yields 2.3 kN of dynamic capacity per height millimetre, and the bearing weighs 970 g for 62.4 kN C — about 16 g per rated kN. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53214 and U 214 are two order numbers shipping as two articles; the installed 32 mm H1 rather than 27 mm H is the dimension the housing drawing must carry.", "applications": [ "vertical process pumps on welded housings", "marine deck-machinery pivots", "heavy hook blocks and lifting equipment" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "cage damage from mounting force applied through the balls instead of the washer face", "tilted running after a mismatched U washer leaves only a narrow band of spherical contact", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Replacement orders must list both 53214 and U 214: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 160 kN static-rated set.", "Minimum axial load still applies with factor A 0.16: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The shaft washer remains the tight, ground-bore component on the 70 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 214 into the register.", "Ordering discipline for 53214: the catalogue page quotes 53214 plus U 214 and its 62.4/160 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53214?", "a": "53214 measures 70 mm bore × 105 mm OD × 27 mm bearing height (2.756 × 4.134 × 1.063 in), or 32 mm mounted H1 including the U 214 seat washer, mass about 970 g. SKF 17000 ratings: C 62.4 kN, C0 160 kN, Pu 5.85 kN, reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical)." }, { "q": "What does the designation 53214 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 14 encode the bore as 70 mm (code 14 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Why does 53214 need a U 214 seat washer?", "a": "The housing washer of 53214 has a sphered back face. The U 214 seat washer presents a matching concave face plus a flat housing face, and without it the convex washer contacts the register at a single point; the pair is what gives the bearing its initial-misalignment capacity." }, { "q": "Is the U 214 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53214 and U 214 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." } ], "cross_ref": [ { "equiv_sku": "51214-SKF", "equiv_brand": "SKF", "level": "full", "note": "Same 70×105×27 mm ISO 104 thrust-ball envelope with catalogue ratings within 10 %; 51214 is the single-direction flat-seat, stamped sheet-steel cage execution of this size — boundary dimensions interchangeable, execution differs. Bearing heights match, but this sphered SKF execution additionally needs its U 214 seat washer and stands 32 mm (H1) when mounted." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53214", "53214 + U 214" ], "locale_variants": {} }, { "sku": "53314", "brand": "SKF", "manufacturer_designation": "53314", "series": "53300-series", "type": "thrust_ball", "d_mm": 70, "D_mm": 125, "B_mm": 44.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 135, "static_load_kN": 320, "fatigue_load_limit_kN": 11.8, "reference_speed_rpm": 1800, "limiting_speed_rpm": 2600, "max_rpm": 2600, "weight_g": 2500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 53314 is an ISO 104 single-direction thrust ball bearing, 70 mm bore and 125 mm OD, with a sphered housing washer and U seat washer, standing 44.2 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 14: bore 70 mm (code 14 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 70×125×44.2 mm (2.756×4.921×1.74 in), 27.5 mm radial section, C 135 kN, C0 320 kN, Pu 11.8 kN. Mounted height H1 48 mm includes the U 314 seat washer; the bearing alone is 44.2 mm high. reference speed 1,800 r/min (thermal) and limiting speed 2,600 r/min (mechanical), catalogue mass 2500 g. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 2,600 r/min while thermal balance under catalogue load sets the 1,800 r/min reference; at dm ≈ 97.5 mm the corresponding dn is approximately 254k mm·r/min. Imperial cross-check for procurement drawings: 2.756 in bore, 4.921 in OD, 1.74 in height, and the 2500 g catalogue mass converts to 2.500 kg (88.2 oz). Sizing arithmetic on the 70 mm bore: 135 kN C over the 27.5 mm radial section gives 4.9 kN per section millimetre, and the 44.2 mm stack height is 1.61× that section — proportions typical of a 53300 thrust section. Rating split for documentation: dynamic 135 kN (L10 life), static 320 kN (safety factor s0), fatigue limit 11.8 kN (adjusted life) — three different uses of three different numbers for 53314, none interchangeable with another. Selection figures for 53314: the C0/C ratio is 2.37, Pu 11.8 kN is about 9 % of C, and the catalogue mass works out to roughly 36 g per millimetre of bore; the printed minimum-load factor is A 0.53. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53314 and U 314 are two order numbers shipping as two articles; the installed 48 mm H1 rather than 44.2 mm H is the dimension the housing drawing must carry.", "applications": [ "vertical process pumps on welded housings", "winch drums on fabricated structures", "marine deck-machinery pivots" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "cage damage from mounting force applied through the balls instead of the washer face", "edge loading on the ball set when the U seat washer is fitted with its concave face reversed", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Replacement orders must list both 53314 and U 314: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 320 kN static-rated set.", "Dimension the housing to the 48 mm mounted height H1 (bearing plus U 314), not the 44.2 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "The shaft washer remains the tight, ground-bore component on the 70 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 314 into the register.", "Minimum axial load still applies with factor A 0.53: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "Ordering discipline for 53314: the catalogue page quotes 53314 plus U 314 and its 135/320 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53314?", "a": "The catalogue envelope is 70×125×44.2 mm plus the 3.8 mm the U 314 seat washer adds to reach H1 48 mm, mass 2500 g; ratings C 135 kN / C0 320 kN / Pu 11.8 kN, reference speed 1,800 r/min (thermal) and limiting speed 2,600 r/min (mechanical)." }, { "q": "What does the designation 53314 mean?", "a": "53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 14: bore 70 mm (code 14 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Is the U 314 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53314 and U 314 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." }, { "q": "Is 53314 bidirectional?", "a": "No, the 53-series is single-direction; for reversing thrust with the same self-aligning feature use the 54-series double-direction execution, which needs two U seat washers." } ], "cross_ref": [ { "equiv_sku": "53314", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53314", "53314 + U 314" ], "locale_variants": {} }, { "sku": "53414-M", "brand": "SKF", "manufacturer_designation": "53414 M", "series": "53400-series", "type": "thrust_ball", "d_mm": 70, "D_mm": 150, "B_mm": 63.6, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 234, "static_load_kN": 550, "fatigue_load_limit_kN": 19.3, "reference_speed_rpm": 1400, "limiting_speed_rpm": 2000, "max_rpm": 2000, "weight_g": 6500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53414 M is SKF's 70 mm-bore single-direction thrust ball bearing in the 53400 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 70×150×63.6 mm U 414 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 14 encode the bore as 70 mm (code 14 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 70×150×63.6 mm (2.756×5.906×2.504 in), 40.0 mm radial section, C 234 kN, C0 550 kN, Pu 19.3 kN. Mounted height H1 69 mm includes the U 414 seat washer; the bearing alone is 63.6 mm high. reference speed 1,400 r/min (thermal) and limiting speed 2,000 r/min (mechanical), catalogue mass 6500 g. Light-load floor: Pu = 19.3 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 53414 M; the number is 8 % of the 234 kN dynamic rating. Speed-ratio note for this exact unit: the reference speed is 1,400 r/min against a 2,000 r/min limiting speed, a reference-to-limit ratio of 0.70. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 1.6 at the 2,000 r/min limiting speed raises the required axial preload to about 77.4 kN; the reference-speed value 37.9 kN is the thermal design point. Envelope economics: the 63.6 mm axial height over a 40.0 mm radial section yields 3.7 kN of dynamic capacity per height millimetre, and the bearing weighs 6500 g for 234 kN C — about 28 g per rated kN. Static-first selection data: 550 kN C0 spread across the 63.6 mm stack gives 8.6 kN of static rating per height millimetre, and the 6500 g mass/C0 ratio is about 12 g per static kN — crane-hook and screw positions are normally sized on these two figures. Heavy sphered-execution note: this M order number combines the machined brass ball-centred cage with the sphered housing washer and its U seat washer; it is the large-bore answer for hook blocks and pivots whose fabricated structure deflects — verify the spherical pair swivels freely under a light preload before the working load goes on. Under 550 kN static load the spherical interface of 53414 M must stay lubricated with a grease that does not separate at rest; a dry sphered contact under hook-block shock frets even though the ball tracks remain unworn.", "applications": [ "large screw jacks on elastic frames", "winch drums on fabricated structures", "heavy hook blocks and lifting equipment" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "pitting on one track sector from a perpetually eccentric thrust line", "total loss of the aligning function after paint, scale or abrasive dust fills the sphered contact", "fretting between the sphered washer and U seat washer when the spherical interface runs dry under oscillation", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The shaft washer remains the tight, ground-bore component on the 70 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 414 into the register.", "Minimum axial load still applies with factor A 1.6: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The sphered housing washer of 53414 M MUST run against the U 414 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 414 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53414 M as the single sphered brass execution; other order numbers of the 53414 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 414 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53414-M?", "a": "53414 M measures 70 mm bore × 150 mm OD × 63.6 mm bearing height (2.756 × 5.906 × 2.504 in), or 69 mm mounted H1 including the U 414 seat washer, mass about 6500 g. SKF 17000 ratings: C 234 kN, C0 550 kN, Pu 19.3 kN, reference speed 1,400 r/min (thermal) and limiting speed 2,000 r/min (mechanical)." }, { "q": "What does the designation 53414 M mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 14 encode the bore as 70 mm (code 14 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." }, { "q": "How much misalignment can 53414-M accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." } ], "cross_ref": [ { "equiv_sku": "53414", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53414-M", "53414 M", "53414 M + U 414" ], "locale_variants": {} }, { "sku": "53215", "brand": "SKF", "manufacturer_designation": "53215", "series": "53200-series", "type": "thrust_ball", "d_mm": 75, "D_mm": 110, "B_mm": 28.3, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 63.7, "static_load_kN": 170, "fatigue_load_limit_kN": 6.2, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53215 is SKF's 75 mm-bore single-direction thrust ball bearing in the 53200 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 75×110×28.3 mm U 215 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 15 encode the bore as 75 mm (code 15 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 75×110×28.3 mm (2.953×4.331×1.114 in), 17.5 mm radial section, C 63.7 kN, C0 170 kN, Pu 6.2 kN. Mounted height H1 32 mm includes the U 215 seat washer; the bearing alone is 28.3 mm high. reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical), catalogue mass 1000 g. Rating split for documentation: dynamic 63.7 kN (L10 life), static 170 kN (safety factor s0), fatigue limit 6.2 kN (adjusted life) — three different uses of three different numbers for 53215, none interchangeable with another. Speed-ratio note for this exact unit: the reference speed is 2,400 r/min against a 3,400 r/min limiting speed, a reference-to-limit ratio of 0.71. Stack/annulus proportions: the 28.3 mm axial stack over the 5,085 mm² washer annulus gives 5.57 mm of height per annular square millimetre ×10⁻³, and at 1000 g the bearing holds about 170.0 kN of C0 per kilogram. Bore-to-OD planning: OD 110 over bore 75 is a 1.47× step for this size, and the 28.3 mm height gives a bore/height ratio of 2.65; use these ratios when the housing recess around the 75 mm shaft is the first constraint. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 3,400 r/min while thermal balance under catalogue load sets the 2,400 r/min reference; at dm ≈ 92.5 mm the corresponding dn is approximately 315k mm·r/min. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 110 mm washer can tilt inside the U 215 seat; check the actual tilt allowance in the mounting drawing, since the 3.7 mm washer thickness step does not by itself quantify it.", "applications": [ "heavy hook blocks and lifting equipment", "winch drums on fabricated structures", "large screw jacks on elastic frames" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "pitting on one track sector from a perpetually eccentric thrust line", "point-contact destruction of the housing register when a sphered washer is operated directly on a flat face without its U seat washer", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Replacement orders must list both 53215 and U 215: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 170 kN static-rated set.", "Dimension the housing to the 32 mm mounted height H1 (bearing plus U 215), not the 28.3 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "Minimum axial load still applies with factor A 0.17: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53215 as the single sphered pressed steel execution; other order numbers of the 53215 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 215 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53215?", "a": "53215 measures 75 mm bore × 110 mm OD × 28.3 mm bearing height (2.953 × 4.331 × 1.114 in), or 32 mm mounted H1 including the U 215 seat washer, mass about 1000 g. SKF 17000 ratings: C 63.7 kN, C0 170 kN, Pu 6.2 kN, reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical)." }, { "q": "What does the designation 53215 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 15 encode the bore as 75 mm (code 15 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." }, { "q": "How much misalignment can 53215 accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." } ], "cross_ref": [ { "equiv_sku": "53215", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53215", "53215 + U 215" ], "locale_variants": {} }, { "sku": "53315", "brand": "SKF", "manufacturer_designation": "53315", "series": "53300-series", "type": "thrust_ball", "d_mm": 75, "D_mm": 135, "B_mm": 48.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 163, "static_load_kN": 390, "fatigue_load_limit_kN": 14, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 3200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 53315 is an ISO 104 single-direction thrust ball bearing, 75 mm bore and 135 mm OD, with a sphered housing washer and U seat washer, standing 48.1 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 15: bore 75 mm (code 15 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 75×135×48.1 mm (2.953×5.315×1.894 in), 30.0 mm radial section, C 163 kN, C0 390 kN, Pu 14 kN. Mounted height H1 52 mm includes the U 315 seat washer; the bearing alone is 48.1 mm high. reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical), catalogue mass 3200 g. Track-circle loading: per millimetre of mean track circumference the 163 kN dynamic rating corresponds to roughly 0.49 kN/mm of π·dm track, a useful comparison against the other dimension series of the 75 mm bore. Capacity density: 163 kN C from 3.200 kg of bearing steel gives about 50.9 kN per kilogram; static density is correspondingly 121.9 kN/kg at C0 390 kN. Stack/annulus proportions: the 48.1 mm axial stack over the 9,896 mm² washer annulus gives 4.86 mm of height per annular square millimetre ×10⁻³, and at 3200 g the bearing holds about 121.9 kN of C0 per kilogram. Pitch-diameter arithmetic: dm = (75+135)/2 = 105.0 mm; at the 2,400 r/min limiting speed that corresponds to roughly 252k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Rating split for documentation: dynamic 163 kN (L10 life), static 390 kN (safety factor s0), fatigue limit 14 kN (adjusted life) — three different uses of three different numbers for 53315, none interchangeable with another. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 135 mm washer can tilt inside the U 315 seat; check the actual tilt allowance in the mounting drawing, since the 3.9 mm washer thickness step does not by itself quantify it.", "applications": [ "marine deck-machinery pivots", "heavy hook blocks and lifting equipment", "winch drums on fabricated structures" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "edge loading on the ball set when the U seat washer is fitted with its concave face reversed", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "false brinelling of the stationary tracks while the machine stands under vibration", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "The shaft washer remains the tight, ground-bore component on the 75 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 315 into the register.", "The sphered housing washer of 53315 MUST run against the U 315 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Replacement orders must list both 53315 and U 315: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 390 kN static-rated set.", "The 163/390 kN figures belong to 53315 specifically (the single sphered pressed steel execution of 53315); suffixed, sphered and counterpart-series order numbers are separate articles, and U 315 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53315?", "a": "The catalogue envelope is 75×135×48.1 mm plus the 3.9 mm the U 315 seat washer adds to reach H1 52 mm, mass 3200 g; ratings C 163 kN / C0 390 kN / Pu 14 kN, reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical)." }, { "q": "What does the designation 53315 mean?", "a": "53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 15: bore 75 mm (code 15 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "How much misalignment can 53315 accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." }, { "q": "What is the difference between H and H1?", "a": "H 48.1 mm is the height of the bearing itself; H1 52 mm is the installed height including the U 315 seat washer. Housing recesses and cover stacks must be drawn to H1, not H." } ], "cross_ref": [ { "equiv_sku": "53315", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53315", "53315 + U 315" ], "locale_variants": {} }, { "sku": "53415-M", "brand": "SKF", "manufacturer_designation": "53415 M", "series": "53400-series", "type": "thrust_ball", "d_mm": 75, "D_mm": 160, "B_mm": 69, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 251, "static_load_kN": 610, "fatigue_load_limit_kN": 20.8, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 8100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 53400 series order number 53415 M is a SKF single-direction thrust ball bearing for a 75 mm seat, built to ISO 104, with a sphered housing washer paired to a U seat washer, 75×160×69 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 15 decodes to 75 mm (code 15 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 75×160×69 mm (2.953×6.299×2.717 in), 42.5 mm radial section, C 251 kN, C0 610 kN, Pu 20.8 kN. Mounted height H1 75 mm includes the U 415 seat washer; the bearing alone is 69 mm high. reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical), catalogue mass 8100 g. Mass and section check: 8100 g inside the 75×160×69 mm outline leaves a 42.5 mm radial section, and the 610 kN static rating is 2.43× the dynamic rating — plan static safety and minimum preload against those figures. Speed planning separates the two ceilings mechanically: the pressed brass cage and balls tolerate 1,800 r/min while thermal balance under catalogue load sets the 1,300 r/min reference; at dm ≈ 117.5 mm the corresponding dn is approximately 212k mm·r/min. Minimum-load arithmetic: with dm ≈ 117.5 mm and factor A 1.9, Fam ≈ A·(n·dm/1000)² at the 1,300 r/min reference speed is about 44.3 kN for 53415 M; below that preload the balls skid and smear the tracks. Speed band width for this size is 500 r/min between reference and limiting (1.38× ratio); lubrication, preload and heat removal decide where inside that band 53415 M can actually run. Envelope economics: the 69 mm axial height over a 42.5 mm radial section yields 3.6 kN of dynamic capacity per height millimetre, and the bearing weighs 8100 g for 251 kN C — about 32 g per rated kN. Heavy sphered-execution note: this M order number combines the machined brass ball-centred cage with the sphered housing washer and its U seat washer; it is the large-bore answer for hook blocks and pivots whose fabricated structure deflects — verify the spherical pair swivels freely under a light preload before the working load goes on. The M brass-cage option at 75 mm bore pairs the heavy-section cage with the U 415 seat requirement — order all three articles (bearing + U washer + appropriate lubricant) together, and log the H1 75 mm installed dimension on the maintenance card.", "applications": [ "heavy hook blocks and lifting equipment", "large screw jacks on elastic frames", "winch drums on fabricated structures" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "total loss of the aligning function after paint, scale or abrasive dust fills the sphered contact", "fretting between the sphered washer and U seat washer when the spherical interface runs dry under oscillation", "track rust staining from condensate during long idle periods in humid plant air", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Dimension the housing to the 75 mm mounted height H1 (bearing plus U 415), not the 69 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "The sphered housing washer of 53415 M MUST run against the U 415 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Minimum axial load still applies with factor A 1.9: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "The 251/610 kN figures belong to 53415 M specifically (the single sphered brass execution of 53415); suffixed, sphered and counterpart-series order numbers are separate articles, and U 415 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53415-M?", "a": "Boundary dimensions to ISO 104: bore 75 mm, OD 160 mm, height 69 mm (H1 75 mm installed with the U 415 seat washer); weight 8100 g. Load figures from SKF 17000: dynamic 251 kN, static 610 kN, fatigue limit 20.8 kN; reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical)." }, { "q": "What does the designation 53415 M mean?", "a": "the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 15 decodes to 75 mm (code 15 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Is 53415 bidirectional?", "a": "No, the 53-series is single-direction; for reversing thrust with the same self-aligning feature use the 54-series double-direction execution, which needs two U seat washers." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." } ], "cross_ref": [ { "equiv_sku": "53415", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53415-M", "53415 M", "53415 M + U 415" ], "locale_variants": {} }, { "sku": "53216", "brand": "SKF", "manufacturer_designation": "53216", "series": "53200-series", "type": "thrust_ball", "d_mm": 80, "D_mm": 115, "B_mm": 29.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 76.1, "static_load_kN": 208, "fatigue_load_limit_kN": 7.65, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 1100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 53216 is an ISO 104 single-direction thrust ball bearing, 80 mm bore and 115 mm OD, with a sphered housing washer and U seat washer, standing 29.5 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 16: bore 80 mm (code 16 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 80×115×29.5 mm (3.15×4.528×1.161 in), 17.5 mm radial section, C 76.1 kN, C0 208 kN, Pu 7.65 kN. Mounted height H1 33 mm includes the U 216 seat washer; the bearing alone is 29.5 mm high. reference speed 2,400 r/min (thermal) and limiting speed 3,200 r/min (mechanical), catalogue mass 1100 g. Pitch-diameter arithmetic: dm = (80+115)/2 = 97.5 mm; at the 3,200 r/min limiting speed that corresponds to roughly 312k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Light-load floor: Pu = 7.65 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 53216; the number is 10 % of the 76.1 kN dynamic rating. Imperial cross-check for procurement drawings: 3.15 in bore, 4.528 in OD, 1.161 in height, and the 1100 g catalogue mass converts to 1.100 kg (38.8 oz). Capacity density: 76.1 kN C from 1.100 kg of bearing steel gives about 69.2 kN per kilogram; static density is correspondingly 189.1 kN/kg at C0 208 kN. Speed band width for this size is 800 r/min between reference and limiting (1.33× ratio); lubrication, preload and heat removal decide where inside that band 53216 can actually run. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53216 and U 216 are two order numbers shipping as two articles; the installed 33 mm H1 rather than 29.5 mm H is the dimension the housing drawing must carry.", "applications": [ "vertical process pumps on welded housings", "heavy hook blocks and lifting equipment", "marine deck-machinery pivots" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "point-contact destruction of the housing register when a sphered washer is operated directly on a flat face without its U seat washer", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "false brinelling of the stationary tracks while the machine stands under vibration", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "Dimension the housing to the 33 mm mounted height H1 (bearing plus U 216), not the 29.5 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "The sphered housing washer of 53216 MUST run against the U 216 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Replacement orders must list both 53216 and U 216: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 208 kN static-rated set.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53216 as the single sphered pressed steel execution; other order numbers of the 53216 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 216 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53216?", "a": "The catalogue envelope is 80×115×29.5 mm plus the 3.5 mm the U 216 seat washer adds to reach H1 33 mm, mass 1100 g; ratings C 76.1 kN / C0 208 kN / Pu 7.65 kN, reference speed 2,400 r/min (thermal) and limiting speed 3,200 r/min (mechanical)." }, { "q": "What does the designation 53216 mean?", "a": "53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 16: bore 80 mm (code 16 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "How much misalignment can 53216 accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." }, { "q": "What is the difference between H and H1?", "a": "H 29.5 mm is the height of the bearing itself; H1 33 mm is the installed height including the U 216 seat washer. Housing recesses and cover stacks must be drawn to H1, not H." } ], "cross_ref": [ { "equiv_sku": "53216", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53216", "53216 + U 216" ], "locale_variants": {} }, { "sku": "53316", "brand": "SKF", "manufacturer_designation": "53316", "series": "53300-series", "type": "thrust_ball", "d_mm": 80, "D_mm": 140, "B_mm": 47.6, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 159, "static_load_kN": 390, "fatigue_load_limit_kN": 13.7, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 3200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 53316 is an ISO 104 single-direction thrust ball bearing, 80 mm bore and 140 mm OD, with a sphered housing washer and U seat washer, standing 47.6 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 16: bore 80 mm (code 16 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 80×140×47.6 mm (3.15×5.512×1.874 in), 30.0 mm radial section, C 159 kN, C0 390 kN, Pu 13.7 kN. Mounted height H1 52 mm includes the U 316 seat washer; the bearing alone is 47.6 mm high. reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical), catalogue mass 3200 g. Sizing arithmetic on the 80 mm bore: 159 kN C over the 30.0 mm radial section gives 5.3 kN per section millimetre, and the 47.6 mm stack height is 1.59× that section — proportions typical of a 53300 thrust section. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 2,200 r/min while thermal balance under catalogue load sets the 1,600 r/min reference; at dm ≈ 110.0 mm the corresponding dn is approximately 242k mm·r/min. Minimum-load arithmetic: with dm ≈ 110.0 mm and factor A 0.79, Fam ≈ A·(n·dm/1000)² at the 1,600 r/min reference speed is about 24.5 kN for 53316; below that preload the balls skid and smear the tracks. Stack/annulus proportions: the 47.6 mm axial stack over the 10,367 mm² washer annulus gives 4.59 mm of height per annular square millimetre ×10⁻³, and at 3200 g the bearing holds about 121.9 kN of C0 per kilogram. Envelope economics: the 47.6 mm axial height over a 30.0 mm radial section yields 3.3 kN of dynamic capacity per height millimetre, and the bearing weighs 3200 g for 159 kN C — about 20 g per rated kN. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 140 mm washer can tilt inside the U 316 seat; check the actual tilt allowance in the mounting drawing, since the 4.4 mm washer thickness step does not by itself quantify it.", "applications": [ "winch drums on fabricated structures", "vertical process pumps on welded housings", "marine deck-machinery pivots" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "total loss of the aligning function after paint, scale or abrasive dust fills the sphered contact", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "The shaft washer remains the tight, ground-bore component on the 80 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 316 into the register.", "Minimum axial load still applies with factor A 0.79: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "The sphered housing washer of 53316 MUST run against the U 316 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53316 as the single sphered pressed steel execution; other order numbers of the 53316 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 316 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53316?", "a": "The catalogue envelope is 80×140×47.6 mm plus the 4.4 mm the U 316 seat washer adds to reach H1 52 mm, mass 3200 g; ratings C 159 kN / C0 390 kN / Pu 13.7 kN, reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical)." }, { "q": "What does the designation 53316 mean?", "a": "53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 16: bore 80 mm (code 16 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Is the U 316 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53316 and U 316 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." }, { "q": "Is 53316 bidirectional?", "a": "No, the 53-series is single-direction; for reversing thrust with the same self-aligning feature use the 54-series double-direction execution, which needs two U seat washers." } ], "cross_ref": [ { "equiv_sku": "53316", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53316", "53316 + U 316" ], "locale_variants": {} }, { "sku": "53217", "brand": "SKF", "manufacturer_designation": "53217", "series": "53200-series", "type": "thrust_ball", "d_mm": 85, "D_mm": 125, "B_mm": 33.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 97.5, "static_load_kN": 275, "fatigue_load_limit_kN": 9, "reference_speed_rpm": 2000, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 53200 series order number 53217 is a SKF single-direction thrust ball bearing for a 85 mm seat, built to ISO 104, with a sphered housing washer paired to a U seat washer, 85×125×33.1 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 17 decodes to 85 mm (code 17 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 85×125×33.1 mm (3.346×4.921×1.303 in), 20.0 mm radial section, C 97.5 kN, C0 275 kN, Pu 9 kN. Mounted height H1 37 mm includes the U 217 seat washer; the bearing alone is 33.1 mm high. reference speed 2,000 r/min (thermal) and limiting speed 3,000 r/min (mechanical), catalogue mass 1500 g. Rating split for documentation: dynamic 97.5 kN (L10 life), static 275 kN (safety factor s0), fatigue limit 9 kN (adjusted life) — three different uses of three different numbers for 53217, none interchangeable with another. Imperial cross-check for procurement drawings: 3.346 in bore, 4.921 in OD, 1.303 in height, and the 1500 g catalogue mass converts to 1.500 kg (52.9 oz). Speed band width for this size is 1,000 r/min between reference and limiting (1.50× ratio); lubrication, preload and heat removal decide where inside that band 53217 can actually run. Washer-stack proportions: the U 217 seat washer adds 3.9 mm to the 33.1 mm bearing height for a mounted H1 of 37 mm, while the 20.0 mm radial section against 85 mm bore (section/bore ≈ 0.24) identifies the envelope. Envelope economics: the 33.1 mm axial height over a 20.0 mm radial section yields 2.9 kN of dynamic capacity per height millimetre, and the bearing weighs 1500 g for 97.5 kN C — about 15 g per rated kN. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 125 mm washer can tilt inside the U 217 seat; check the actual tilt allowance in the mounting drawing, since the 3.9 mm washer thickness step does not by itself quantify it.", "applications": [ "large screw jacks on elastic frames", "winch drums on fabricated structures", "vertical process pumps on welded housings" ], "failure_modes": [ "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "point-contact destruction of the housing register when a sphered washer is operated directly on a flat face without its U seat washer", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Replacement orders must list both 53217 and U 217: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 275 kN static-rated set.", "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 217 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "Minimum axial load still applies with factor A 0.39: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The 97.5/275 kN figures belong to 53217 specifically (the single sphered pressed steel execution of 53217); suffixed, sphered and counterpart-series order numbers are separate articles, and U 217 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53217?", "a": "Boundary dimensions to ISO 104: bore 85 mm, OD 125 mm, height 33.1 mm (H1 37 mm installed with the U 217 seat washer); weight 1500 g. Load figures from SKF 17000: dynamic 97.5 kN, static 275 kN, fatigue limit 9 kN; reference speed 2,000 r/min (thermal) and limiting speed 3,000 r/min (mechanical)." }, { "q": "What does the designation 53217 mean?", "a": "the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 17 decodes to 85 mm (code 17 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "What is the difference between H and H1?", "a": "H 33.1 mm is the height of the bearing itself; H1 37 mm is the installed height including the U 217 seat washer. Housing recesses and cover stacks must be drawn to H1, not H." }, { "q": "Why does 53217 need a U 217 seat washer?", "a": "The housing washer of 53217 has a sphered back face. The U 217 seat washer presents a matching concave face plus a flat housing face, and without it the convex washer contacts the register at a single point; the pair is what gives the bearing its initial-misalignment capacity." } ], "cross_ref": [ { "equiv_sku": "53217", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53217", "53217 + U 217" ], "locale_variants": {} }, { "sku": "53317", "brand": "SKF", "manufacturer_designation": "53317", "series": "53300-series", "type": "thrust_ball", "d_mm": 85, "D_mm": 150, "B_mm": 53.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 174, "static_load_kN": 405, "fatigue_load_limit_kN": 14, "reference_speed_rpm": 1500, "limiting_speed_rpm": 2000, "max_rpm": 2000, "weight_g": 4350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53317 is SKF's 85 mm-bore single-direction thrust ball bearing in the 53300 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 85×150×53.1 mm U 317 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 17 encode the bore as 85 mm (code 17 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 85×150×53.1 mm (3.346×5.906×2.091 in), 32.5 mm radial section, C 174 kN, C0 405 kN, Pu 14 kN. Mounted height H1 58 mm includes the U 317 seat washer; the bearing alone is 53.1 mm high. reference speed 1,500 r/min (thermal) and limiting speed 2,000 r/min (mechanical), catalogue mass 4350 g. Washer-stack proportions: the U 317 seat washer adds 4.9 mm to the 53.1 mm bearing height for a mounted H1 of 58 mm, while the 32.5 mm radial section against 85 mm bore (section/bore ≈ 0.38) identifies the envelope. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 1.1 at the 2,000 r/min limiting speed raises the required axial preload to about 60.7 kN; the reference-speed value 34.2 kN is the thermal design point. Rating split for documentation: dynamic 174 kN (L10 life), static 405 kN (safety factor s0), fatigue limit 14 kN (adjusted life) — three different uses of three different numbers for 53317, none interchangeable with another. Capacity density: 174 kN C from 4.350 kg of bearing steel gives about 40.0 kN per kilogram; static density is correspondingly 93.1 kN/kg at C0 405 kN. Mass and section check: 4350 g inside the 85×150×53.1 mm outline leaves a 32.5 mm radial section, and the 405 kN static rating is 2.33× the dynamic rating — plan static safety and minimum preload against those figures. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 150 mm washer can tilt inside the U 317 seat; check the actual tilt allowance in the mounting drawing, since the 4.9 mm washer thickness step does not by itself quantify it.", "applications": [ "marine deck-machinery pivots", "heavy hook blocks and lifting equipment", "winch drums on fabricated structures" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "grease channel failure on a vertical shaft when the upper washer runs dry before the first service interval", "corrosion lock of the spherical pair during long outdoor idleness with no preservative grease", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "false brinelling of the stationary tracks while the machine stands under vibration", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Replacement orders must list both 53317 and U 317: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 405 kN static-rated set.", "Dimension the housing to the 58 mm mounted height H1 (bearing plus U 317), not the 53.1 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "The shaft washer remains the tight, ground-bore component on the 85 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 317 into the register.", "Ordering discipline for 53317: the catalogue page quotes 53317 plus U 317 and its 174/405 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53317?", "a": "53317 measures 85 mm bore × 150 mm OD × 53.1 mm bearing height (3.346 × 5.906 × 2.091 in), or 58 mm mounted H1 including the U 317 seat washer, mass about 4350 g. SKF 17000 ratings: C 174 kN, C0 405 kN, Pu 14 kN, reference speed 1,500 r/min (thermal) and limiting speed 2,000 r/min (mechanical)." }, { "q": "What does the designation 53317 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 17 encode the bore as 85 mm (code 17 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Why does 53317 need a U 317 seat washer?", "a": "The housing washer of 53317 has a sphered back face. The U 317 seat washer presents a matching concave face plus a flat housing face, and without it the convex washer contacts the register at a single point; the pair is what gives the bearing its initial-misalignment capacity." }, { "q": "Is the U 317 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53317 and U 317 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." } ], "cross_ref": [ { "equiv_sku": "53317", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53317", "53317 + U 317" ], "locale_variants": {} }, { "sku": "53218", "brand": "SKF", "manufacturer_designation": "53218", "series": "53200-series", "type": "thrust_ball", "d_mm": 90, "D_mm": 135, "B_mm": 38.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 112, "static_load_kN": 290, "fatigue_load_limit_kN": 10.4, "reference_speed_rpm": 1900, "limiting_speed_rpm": 2600, "max_rpm": 2600, "weight_g": 2100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53218 is SKF's 90 mm-bore single-direction thrust ball bearing in the 53200 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 90×135×38.5 mm U 218 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 18 encode the bore as 90 mm (code 18 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 90×135×38.5 mm (3.543×5.315×1.516 in), 22.5 mm radial section, C 112 kN, C0 290 kN, Pu 10.4 kN. Mounted height H1 42 mm includes the U 218 seat washer; the bearing alone is 38.5 mm high. reference speed 1,900 r/min (thermal) and limiting speed 2,600 r/min (mechanical), catalogue mass 2100 g. Rating split for documentation: dynamic 112 kN (L10 life), static 290 kN (safety factor s0), fatigue limit 10.4 kN (adjusted life) — three different uses of three different numbers for 53218, none interchangeable with another. Pitch-diameter arithmetic: dm = (90+135)/2 = 112.5 mm; at the 2,600 r/min limiting speed that corresponds to roughly 293k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 2,600 r/min while thermal balance under catalogue load sets the 1,900 r/min reference; at dm ≈ 112.5 mm the corresponding dn is approximately 293k mm·r/min. Load balance: C0 290 kN against C 112 kN gives a 2.59 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 10.4 kN enters the adjusted-life check. Mass and section check: 2100 g inside the 90×135×38.5 mm outline leaves a 22.5 mm radial section, and the 290 kN static rating is 2.59× the dynamic rating — plan static safety and minimum preload against those figures. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53218 and U 218 are two order numbers shipping as two articles; the installed 42 mm H1 rather than 38.5 mm H is the dimension the housing drawing must carry.", "applications": [ "heavy hook blocks and lifting equipment", "marine deck-machinery pivots", "large screw jacks on elastic frames" ], "failure_modes": [ "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "point-contact destruction of the housing register when a sphered washer is operated directly on a flat face without its U seat washer", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Dimension the housing to the 42 mm mounted height H1 (bearing plus U 218), not the 38.5 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "The sphered housing washer of 53218 MUST run against the U 218 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Replacement orders must list both 53218 and U 218: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 290 kN static-rated set.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53218 as the single sphered pressed steel execution; other order numbers of the 53218 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 218 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53218?", "a": "53218 measures 90 mm bore × 135 mm OD × 38.5 mm bearing height (3.543 × 5.315 × 1.516 in), or 42 mm mounted H1 including the U 218 seat washer, mass about 2100 g. SKF 17000 ratings: C 112 kN, C0 290 kN, Pu 10.4 kN, reference speed 1,900 r/min (thermal) and limiting speed 2,600 r/min (mechanical)." }, { "q": "What does the designation 53218 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 18 encode the bore as 90 mm (code 18 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Why does 53218 need a U 218 seat washer?", "a": "The housing washer of 53218 has a sphered back face. The U 218 seat washer presents a matching concave face plus a flat housing face, and without it the convex washer contacts the register at a single point; the pair is what gives the bearing its initial-misalignment capacity." }, { "q": "Is the U 218 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53218 and U 218 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." } ], "cross_ref": [ { "equiv_sku": "53218", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53218", "53218 + U 218" ], "locale_variants": {} }, { "sku": "53318", "brand": "SKF", "manufacturer_designation": "53318", "series": "53300-series", "type": "thrust_ball", "d_mm": 90, "D_mm": 155, "B_mm": 54.6, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 182, "static_load_kN": 440, "fatigue_load_limit_kN": 14.6, "reference_speed_rpm": 1400, "limiting_speed_rpm": 2000, "max_rpm": 2000, "weight_g": 4700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 53318 is an ISO 104 single-direction thrust ball bearing, 90 mm bore and 155 mm OD, with a sphered housing washer and U seat washer, standing 54.6 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 18: bore 90 mm (code 18 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 90×155×54.6 mm (3.543×6.102×2.15 in), 32.5 mm radial section, C 182 kN, C0 440 kN, Pu 14.6 kN. Mounted height H1 59 mm includes the U 318 seat washer; the bearing alone is 54.6 mm high. reference speed 1,400 r/min (thermal) and limiting speed 2,000 r/min (mechanical), catalogue mass 4700 g. Capacity density: 182 kN C from 4.700 kg of bearing steel gives about 38.7 kN per kilogram; static density is correspondingly 93.6 kN/kg at C0 440 kN. At the printed limiting speed of 2,000 r/min the mean pitch diameter dm ≈ 122.5 mm implies a dn value around 245k mm·r/min; the 1,400 r/min reference speed is the thermal-planning value under catalogue load. Sizing arithmetic on the 90 mm bore: 182 kN C over the 32.5 mm radial section gives 5.6 kN per section millimetre, and the 54.6 mm stack height is 1.68× that section — proportions typical of a 53300 thrust section. Pitch-diameter arithmetic: dm = (90+155)/2 = 122.5 mm; at the 2,000 r/min limiting speed that corresponds to roughly 245k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Washer-annulus check: the π/4·(D²−d²) contact annulus of 53318 covers about 12,507 mm², distributing C0 440 kN over a mean track circle of π·dm ≈ 385 mm. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 155 mm washer can tilt inside the U 318 seat; check the actual tilt allowance in the mounting drawing, since the 4.4 mm washer thickness step does not by itself quantify it.", "applications": [ "vertical process pumps on welded housings", "marine deck-machinery pivots", "heavy hook blocks and lifting equipment" ], "failure_modes": [ "cage damage from mounting force applied through the balls instead of the washer face", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "point-contact destruction of the housing register when a sphered washer is operated directly on a flat face without its U seat washer", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Replacement orders must list both 53318 and U 318: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 440 kN static-rated set.", "Dimension the housing to the 59 mm mounted height H1 (bearing plus U 318), not the 54.6 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "Minimum axial load still applies with factor A 1.3: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53318 as the single sphered pressed steel execution; other order numbers of the 53318 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 318 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53318?", "a": "The catalogue envelope is 90×155×54.6 mm plus the 4.4 mm the U 318 seat washer adds to reach H1 59 mm, mass 4700 g; ratings C 182 kN / C0 440 kN / Pu 14.6 kN, reference speed 1,400 r/min (thermal) and limiting speed 2,000 r/min (mechanical)." }, { "q": "What does the designation 53318 mean?", "a": "53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 18: bore 90 mm (code 18 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Is the U 318 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53318 and U 318 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." }, { "q": "Is 53318 bidirectional?", "a": "No, the 53-series is single-direction; for reversing thrust with the same self-aligning feature use the 54-series double-direction execution, which needs two U seat washers." } ], "cross_ref": [ { "equiv_sku": "53318", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53318", "53318 + U 318" ], "locale_variants": {} }, { "sku": "53418-M", "brand": "SKF", "manufacturer_designation": "53418 M", "series": "53400-series", "type": "thrust_ball", "d_mm": 90, "D_mm": 190, "B_mm": 81.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 307, "static_load_kN": 815, "fatigue_load_limit_kN": 25.5, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1500, "max_rpm": 1500, "weight_g": 13000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53418 M is SKF's 90 mm-bore single-direction thrust ball bearing in the 53400 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 90×190×81.2 mm U 418 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 18 encode the bore as 90 mm (code 18 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 90×190×81.2 mm (3.543×7.48×3.197 in), 50.0 mm radial section, C 307 kN, C0 815 kN, Pu 25.5 kN. Mounted height H1 88 mm includes the U 418 seat washer; the bearing alone is 81.2 mm high. reference speed 1,100 r/min (thermal) and limiting speed 1,500 r/min (mechanical), catalogue mass 13000 g. Washer-stack proportions: the U 418 seat washer adds 6.8 mm to the 81.2 mm bearing height for a mounted H1 of 88 mm, while the 50.0 mm radial section against 90 mm bore (section/bore ≈ 0.56) identifies the envelope. Selection figures for 53418 M: the C0/C ratio is 2.65, Pu 25.5 kN is about 8 % of C, and the catalogue mass works out to roughly 144 g per millimetre of bore; the printed minimum-load factor is A 3.5. Speed band width for this size is 400 r/min between reference and limiting (1.36× ratio); lubrication, preload and heat removal decide where inside that band 53418 M can actually run. At the printed limiting speed of 1,500 r/min the mean pitch diameter dm ≈ 140.0 mm implies a dn value around 210k mm·r/min; the 1,100 r/min reference speed is the thermal-planning value under catalogue load. Pitch-diameter arithmetic: dm = (90+190)/2 = 140.0 mm; at the 1,500 r/min limiting speed that corresponds to roughly 210k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Heavy sphered-execution note: this M order number combines the machined brass ball-centred cage with the sphered housing washer and its U seat washer; it is the large-bore answer for hook blocks and pivots whose fabricated structure deflects — verify the spherical pair swivels freely under a light preload before the working load goes on. The M brass-cage option at 90 mm bore pairs the heavy-section cage with the U 418 seat requirement — order all three articles (bearing + U washer + appropriate lubricant) together, and log the H1 88 mm installed dimension on the maintenance card.", "applications": [ "heavy hook blocks and lifting equipment", "large screw jacks on elastic frames", "winch drums on fabricated structures" ], "failure_modes": [ "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "edge loading on the ball set when the U seat washer is fitted with its concave face reversed", "fretting between the sphered washer and U seat washer when the spherical interface runs dry under oscillation", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The sphered housing washer of 53418 M MUST run against the U 418 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 418 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "Dimension the housing to the 88 mm mounted height H1 (bearing plus U 418), not the 81.2 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "The 307/815 kN figures belong to 53418 M specifically (the single sphered brass execution of 53418); suffixed, sphered and counterpart-series order numbers are separate articles, and U 418 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53418-M?", "a": "53418 M measures 90 mm bore × 190 mm OD × 81.2 mm bearing height (3.543 × 7.48 × 3.197 in), or 88 mm mounted H1 including the U 418 seat washer, mass about 13000 g. SKF 17000 ratings: C 307 kN, C0 815 kN, Pu 25.5 kN, reference speed 1,100 r/min (thermal) and limiting speed 1,500 r/min (mechanical)." }, { "q": "What does the designation 53418 M mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 18 encode the bore as 90 mm (code 18 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." }, { "q": "How much misalignment can 53418-M accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." } ], "cross_ref": [ { "equiv_sku": "53418", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53418-M", "53418 M", "53418 M + U 418" ], "locale_variants": {} }, { "sku": "53220", "brand": "SKF", "manufacturer_designation": "53220", "series": "53200-series", "type": "thrust_ball", "d_mm": 100, "D_mm": 150, "B_mm": 40.9, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 119, "static_load_kN": 325, "fatigue_load_limit_kN": 10.8, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 2700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 53200 series order number 53220 is a SKF single-direction thrust ball bearing for a 100 mm seat, built to ISO 104, with a sphered housing washer paired to a U seat washer, 100×150×40.9 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 20 decodes to 100 mm (code 20 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 100×150×40.9 mm (3.937×5.906×1.61 in), 25.0 mm radial section, C 119 kN, C0 325 kN, Pu 10.8 kN. Mounted height H1 45 mm includes the U 220 seat washer; the bearing alone is 40.9 mm high. reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical), catalogue mass 2700 g. Stack/annulus proportions: the 40.9 mm axial stack over the 9,817 mm² washer annulus gives 4.17 mm of height per annular square millimetre ×10⁻³, and at 2700 g the bearing holds about 120.4 kN of C0 per kilogram. Speed-ratio note for this exact unit: the reference speed is 1,700 r/min against a 2,400 r/min limiting speed, a reference-to-limit ratio of 0.71. Load balance: C0 325 kN against C 119 kN gives a 2.73 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 10.8 kN enters the adjusted-life check. Washer-stack proportions: the U 220 seat washer adds 4.1 mm to the 40.9 mm bearing height for a mounted H1 of 45 mm, while the 25.0 mm radial section against 100 mm bore (section/bore ≈ 0.25) identifies the envelope. Speed band width for this size is 700 r/min between reference and limiting (1.41× ratio); lubrication, preload and heat removal decide where inside that band 53220 can actually run. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 150 mm washer can tilt inside the U 220 seat; check the actual tilt allowance in the mounting drawing, since the 4.1 mm washer thickness step does not by itself quantify it.", "applications": [ "winch drums on fabricated structures", "marine deck-machinery pivots", "vertical process pumps on welded housings" ], "failure_modes": [ "housing-washer creep and seat fretting where the loose washer is not positively located in its bore", "pitting on one track sector from a perpetually eccentric thrust line", "point-contact destruction of the housing register when a sphered washer is operated directly on a flat face without its U seat washer", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The shaft washer remains the tight, ground-bore component on the 100 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 220 into the register.", "Minimum axial load still applies with factor A 0.62: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "Dimension the housing to the 45 mm mounted height H1 (bearing plus U 220), not the 40.9 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "The sphered housing washer of 53220 MUST run against the U 220 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53220 as the single sphered pressed steel execution; other order numbers of the 53220 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 220 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53220?", "a": "Boundary dimensions to ISO 104: bore 100 mm, OD 150 mm, height 40.9 mm (H1 45 mm installed with the U 220 seat washer); weight 2700 g. Load figures from SKF 17000: dynamic 119 kN, static 325 kN, fatigue limit 10.8 kN; reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical)." }, { "q": "What does the designation 53220 mean?", "a": "the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 20 decodes to 100 mm (code 20 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "What is the difference between H and H1?", "a": "H 40.9 mm is the height of the bearing itself; H1 45 mm is the installed height including the U 220 seat washer. Housing recesses and cover stacks must be drawn to H1, not H." }, { "q": "Why does 53220 need a U 220 seat washer?", "a": "The housing washer of 53220 has a sphered back face. The U 220 seat washer presents a matching concave face plus a flat housing face, and without it the convex washer contacts the register at a single point; the pair is what gives the bearing its initial-misalignment capacity." } ], "cross_ref": [ { "equiv_sku": "53220", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53220", "53220 + U 220" ], "locale_variants": {} }, { "sku": "53320", "brand": "SKF", "manufacturer_designation": "53320", "series": "53300-series", "type": "thrust_ball", "d_mm": 100, "D_mm": 170, "B_mm": 59.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 225, "static_load_kN": 570, "fatigue_load_limit_kN": 18.3, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 5950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53320 is SKF's 100 mm-bore single-direction thrust ball bearing in the 53300 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 100×170×59.2 mm U 320 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 20 encode the bore as 100 mm (code 20 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 100×170×59.2 mm (3.937×6.693×2.331 in), 35.0 mm radial section, C 225 kN, C0 570 kN, Pu 18.3 kN. Mounted height H1 64 mm includes the U 320 seat washer; the bearing alone is 59.2 mm high. reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical), catalogue mass 5950 g. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 1,800 r/min while thermal balance under catalogue load sets the 1,300 r/min reference; at dm ≈ 135.0 mm the corresponding dn is approximately 243k mm·r/min. Mass and section check: 5950 g inside the 100×170×59.2 mm outline leaves a 35.0 mm radial section, and the 570 kN static rating is 2.53× the dynamic rating — plan static safety and minimum preload against those figures. Rating split for documentation: dynamic 225 kN (L10 life), static 570 kN (safety factor s0), fatigue limit 18.3 kN (adjusted life) — three different uses of three different numbers for 53320, none interchangeable with another. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 1.9 at the 1,800 r/min limiting speed raises the required axial preload to about 112.2 kN; the reference-speed value 58.5 kN is the thermal design point. Capacity density: 225 kN C from 5.950 kg of bearing steel gives about 37.8 kN per kilogram; static density is correspondingly 95.8 kN/kg at C0 570 kN. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 170 mm washer can tilt inside the U 320 seat; check the actual tilt allowance in the mounting drawing, since the 4.8 mm washer thickness step does not by itself quantify it.", "applications": [ "winch drums on fabricated structures", "marine deck-machinery pivots", "vertical process pumps on welded housings" ], "failure_modes": [ "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "corrosion lock of the spherical pair during long outdoor idleness with no preservative grease", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "The shaft washer remains the tight, ground-bore component on the 100 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 320 into the register.", "The sphered housing washer of 53320 MUST run against the U 320 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Replacement orders must list both 53320 and U 320: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 570 kN static-rated set.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53320 as the single sphered pressed steel execution; other order numbers of the 53320 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 320 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53320?", "a": "53320 measures 100 mm bore × 170 mm OD × 59.2 mm bearing height (3.937 × 6.693 × 2.331 in), or 64 mm mounted H1 including the U 320 seat washer, mass about 5950 g. SKF 17000 ratings: C 225 kN, C0 570 kN, Pu 18.3 kN, reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical)." }, { "q": "What does the designation 53320 mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 20 encode the bore as 100 mm (code 20 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Why does 53320 need a U 320 seat washer?", "a": "The housing washer of 53320 has a sphered back face. The U 320 seat washer presents a matching concave face plus a flat housing face, and without it the convex washer contacts the register at a single point; the pair is what gives the bearing its initial-misalignment capacity." }, { "q": "Is the U 320 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53320 and U 320 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." } ], "cross_ref": [ { "equiv_sku": "53320", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53320", "53320 + U 320" ], "locale_variants": {} }, { "sku": "53420-M", "brand": "SKF", "manufacturer_designation": "53420 M", "series": "53400-series", "type": "thrust_ball", "d_mm": 100, "D_mm": 210, "B_mm": 90, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 371, "static_load_kN": 1060, "fatigue_load_limit_kN": 31.5, "reference_speed_rpm": 950, "limiting_speed_rpm": 1300, "max_rpm": 1300, "weight_g": 18000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53420 M is SKF's 100 mm-bore single-direction thrust ball bearing in the 53400 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 100×210×90 mm U 420 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 20 encode the bore as 100 mm (code 20 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 100×210×90 mm (3.937×8.268×3.543 in), 55.0 mm radial section, C 371 kN, C0 1060 kN, Pu 31.5 kN. Mounted height H1 98 mm includes the U 420 seat washer; the bearing alone is 90 mm high. reference speed 950 r/min (thermal) and limiting speed 1,300 r/min (mechanical), catalogue mass 18000 g. Stack/annulus proportions: the 90 mm axial stack over the 26,782 mm² washer annulus gives 3.36 mm of height per annular square millimetre ×10⁻³, and at 18000 g the bearing holds about 58.9 kN of C0 per kilogram. Load balance: C0 1060 kN against C 371 kN gives a 2.86 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 31.5 kN enters the adjusted-life check. Selection figures for 53420 M: the C0/C ratio is 2.86, Pu 31.5 kN is about 8 % of C, and the catalogue mass works out to roughly 180 g per millimetre of bore; the printed minimum-load factor is A 5.8. Sizing arithmetic on the 100 mm bore: 371 kN C over the 55.0 mm radial section gives 6.7 kN per section millimetre, and the 90 mm stack height is 1.64× that section — proportions typical of a 53400 thrust section. Speed-ratio note for this exact unit: the reference speed is 950 r/min against a 1,300 r/min limiting speed, a reference-to-limit ratio of 0.73. Heavy sphered-execution note: this M order number combines the machined brass ball-centred cage with the sphered housing washer and its U seat washer; it is the large-bore answer for hook blocks and pivots whose fabricated structure deflects — verify the spherical pair swivels freely under a light preload before the working load goes on. The M brass-cage option at 100 mm bore pairs the heavy-section cage with the U 420 seat requirement — order all three articles (bearing + U washer + appropriate lubricant) together, and log the H1 98 mm installed dimension on the maintenance card.", "applications": [ "large screw jacks on elastic frames", "vertical process pumps on welded housings", "winch drums on fabricated structures" ], "failure_modes": [ "ball skidding and track smearing once the applied thrust falls below the catalogue minimum axial load at high speed", "pitting on one track sector from a perpetually eccentric thrust line", "point-contact destruction of the housing register when a sphered washer is operated directly on a flat face without its U seat washer", "fretting between the sphered washer and U seat washer when the spherical interface runs dry under oscillation", "track rust staining from condensate during long idle periods in humid plant air", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Dimension the housing to the 98 mm mounted height H1 (bearing plus U 420), not the 90 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "The sphered housing washer of 53420 M MUST run against the U 420 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Replacement orders must list both 53420 M and U 420: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 1060 kN static-rated set.", "The 371/1060 kN figures belong to 53420 M specifically (the single sphered brass execution of 53420); suffixed, sphered and counterpart-series order numbers are separate articles, and U 420 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53420-M?", "a": "53420 M measures 100 mm bore × 210 mm OD × 90 mm bearing height (3.937 × 8.268 × 3.543 in), or 98 mm mounted H1 including the U 420 seat washer, mass about 18000 g. SKF 17000 ratings: C 371 kN, C0 1060 kN, Pu 31.5 kN, reference speed 950 r/min (thermal) and limiting speed 1,300 r/min (mechanical)." }, { "q": "What does the designation 53420 M mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 20 encode the bore as 100 mm (code 20 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Why does 53420-M need a U 420 seat washer?", "a": "The housing washer of 53420 M has a sphered back face. The U 420 seat washer presents a matching concave face plus a flat housing face, and without it the convex washer contacts the register at a single point; the pair is what gives the bearing its initial-misalignment capacity." }, { "q": "Is the U 420 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53420 M and U 420 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." } ], "cross_ref": [ { "equiv_sku": "53420", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53420-M", "53420 M", "53420 M + U 420" ], "locale_variants": {} }, { "sku": "53222", "brand": "SKF", "manufacturer_designation": "53222", "series": "53200-series", "type": "thrust_ball", "d_mm": 110, "D_mm": 160, "B_mm": 40.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 125, "static_load_kN": 365, "fatigue_load_limit_kN": 11.6, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 2900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 53200 series order number 53222 is a SKF single-direction thrust ball bearing for a 110 mm seat, built to ISO 104, with a sphered housing washer paired to a U seat washer, 110×160×40.2 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 22 decodes to 110 mm (code 22 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 110×160×40.2 mm (4.331×6.299×1.583 in), 25.0 mm radial section, C 125 kN, C0 365 kN, Pu 11.6 kN. Mounted height H1 45 mm includes the U 222 seat washer; the bearing alone is 40.2 mm high. reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical), catalogue mass 2900 g. Selection figures for 53222: the C0/C ratio is 2.92, Pu 11.6 kN is about 9 % of C, and the catalogue mass works out to roughly 26 g per millimetre of bore; the printed minimum-load factor is A 0.79. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 2,400 r/min while thermal balance under catalogue load sets the 1,700 r/min reference; at dm ≈ 135.0 mm the corresponding dn is approximately 324k mm·r/min. Speed-ratio note for this exact unit: the reference speed is 1,700 r/min against a 2,400 r/min limiting speed, a reference-to-limit ratio of 0.71. Sizing arithmetic on the 110 mm bore: 125 kN C over the 25.0 mm radial section gives 5.0 kN per section millimetre, and the 40.2 mm stack height is 1.61× that section — proportions typical of a 53200 thrust section. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.79 at the 2,400 r/min limiting speed raises the required axial preload to about 82.9 kN; the reference-speed value 41.6 kN is the thermal design point. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53222 and U 222 are two order numbers shipping as two articles; the installed 45 mm H1 rather than 40.2 mm H is the dimension the housing drawing must carry.", "applications": [ "winch drums on fabricated structures", "vertical process pumps on welded housings", "marine deck-machinery pivots" ], "failure_modes": [ "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "corrosion lock of the spherical pair during long outdoor idleness with no preservative grease", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Replacement orders must list both 53222 and U 222: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 365 kN static-rated set.", "Dimension the housing to the 45 mm mounted height H1 (bearing plus U 222), not the 40.2 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 222 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "The shaft washer remains the tight, ground-bore component on the 110 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 222 into the register.", "Ordering discipline for 53222: the catalogue page quotes 53222 plus U 222 and its 125/365 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53222?", "a": "Boundary dimensions to ISO 104: bore 110 mm, OD 160 mm, height 40.2 mm (H1 45 mm installed with the U 222 seat washer); weight 2900 g. Load figures from SKF 17000: dynamic 125 kN, static 365 kN, fatigue limit 11.6 kN; reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical)." }, { "q": "What does the designation 53222 mean?", "a": "the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 22 decodes to 110 mm (code 22 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "What is the difference between H and H1?", "a": "H 40.2 mm is the height of the bearing itself; H1 45 mm is the installed height including the U 222 seat washer. Housing recesses and cover stacks must be drawn to H1, not H." }, { "q": "Why does 53222 need a U 222 seat washer?", "a": "The housing washer of 53222 has a sphered back face. The U 222 seat washer presents a matching concave face plus a flat housing face, and without it the convex washer contacts the register at a single point; the pair is what gives the bearing its initial-misalignment capacity." } ], "cross_ref": [ { "equiv_sku": "53222", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53222", "53222 + U 222" ], "locale_variants": {} }, { "sku": "53322-M", "brand": "SKF", "manufacturer_designation": "53322 M", "series": "53300-series", "type": "thrust_ball", "d_mm": 110, "D_mm": 190, "B_mm": 67.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 281, "static_load_kN": 815, "fatigue_load_limit_kN": 24.5, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1600, "max_rpm": 1600, "weight_g": 9100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53322 M is SKF's 110 mm-bore single-direction thrust ball bearing in the 53300 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 110×190×67.2 mm U 322 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 22 encode the bore as 110 mm (code 22 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 110×190×67.2 mm (4.331×7.48×2.646 in), 40.0 mm radial section, C 281 kN, C0 815 kN, Pu 24.5 kN. Mounted height H1 72 mm includes the U 322 seat washer; the bearing alone is 67.2 mm high. reference speed 1,100 r/min (thermal) and limiting speed 1,600 r/min (mechanical), catalogue mass 9100 g. Selection figures for 53322 M: the C0/C ratio is 2.90, Pu 24.5 kN is about 9 % of C, and the catalogue mass works out to roughly 83 g per millimetre of bore; the printed minimum-load factor is A 3.2. Static-first selection data: 815 kN C0 spread across the 67.2 mm stack gives 12.1 kN of static rating per height millimetre, and the 9100 g mass/C0 ratio is about 11 g per static kN — crane-hook and screw positions are normally sized on these two figures. At the printed limiting speed of 1,600 r/min the mean pitch diameter dm ≈ 150.0 mm implies a dn value around 240k mm·r/min; the 1,100 r/min reference speed is the thermal-planning value under catalogue load. Rating split for documentation: dynamic 281 kN (L10 life), static 815 kN (safety factor s0), fatigue limit 24.5 kN (adjusted life) — three different uses of three different numbers for 53322 M, none interchangeable with another. Pitch-diameter arithmetic: dm = (110+190)/2 = 150.0 mm; at the 1,600 r/min limiting speed that corresponds to roughly 240k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Heavy sphered-execution note: this M order number combines the machined brass ball-centred cage with the sphered housing washer and its U seat washer; it is the large-bore answer for hook blocks and pivots whose fabricated structure deflects — verify the spherical pair swivels freely under a light preload before the working load goes on. The M brass-cage option at 110 mm bore pairs the heavy-section cage with the U 322 seat requirement — order all three articles (bearing + U washer + appropriate lubricant) together, and log the H1 72 mm installed dimension on the maintenance card.", "applications": [ "heavy hook blocks and lifting equipment", "vertical process pumps on welded housings", "large screw jacks on elastic frames" ], "failure_modes": [ "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "raceway spalling when reversing axial force is applied to a single-direction bearing and the unloaded washer lifts off its track", "fretting corrosion in the spherical interface under oscillation with no grease between washer and seat", "fretting between the sphered washer and U seat washer when the spherical interface runs dry under oscillation", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The sphered housing washer of 53322 M MUST run against the U 322 seat washer, a separate order number; mounted bare on a flat register, the convex back makes point contact that gouges the housing under load.", "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 322 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "Dimension the housing to the 72 mm mounted height H1 (bearing plus U 322), not the 67.2 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "The 281/815 kN figures belong to 53322 M specifically (the single sphered brass execution of 53322); suffixed, sphered and counterpart-series order numbers are separate articles, and U 322 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53322-M?", "a": "53322 M measures 110 mm bore × 190 mm OD × 67.2 mm bearing height (4.331 × 7.48 × 2.646 in), or 72 mm mounted H1 including the U 322 seat washer, mass about 9100 g. SKF 17000 ratings: C 281 kN, C0 815 kN, Pu 24.5 kN, reference speed 1,100 r/min (thermal) and limiting speed 1,600 r/min (mechanical)." }, { "q": "What does the designation 53322 M mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 22 encode the bore as 110 mm (code 22 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." }, { "q": "How much misalignment can 53322-M accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." } ], "cross_ref": [ { "equiv_sku": "53322", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53322-M", "53322 M", "53322 M + U 322" ], "locale_variants": {} }, { "sku": "53224", "brand": "SKF", "manufacturer_designation": "53224", "series": "53200-series", "type": "thrust_ball", "d_mm": 120, "D_mm": 170, "B_mm": 40.8, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 127, "static_load_kN": 390, "fatigue_load_limit_kN": 11.8, "reference_speed_rpm": 1500, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 3200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 53224 is an ISO 104 single-direction thrust ball bearing, 120 mm bore and 170 mm OD, with a sphered housing washer and U seat washer, standing 40.8 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 24: bore 120 mm (code 24 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 120×170×40.8 mm (4.724×6.693×1.606 in), 25.0 mm radial section, C 127 kN, C0 390 kN, Pu 11.8 kN. Mounted height H1 46 mm includes the U 224 seat washer; the bearing alone is 40.8 mm high. reference speed 1,500 r/min (thermal) and limiting speed 2,200 r/min (mechanical), catalogue mass 3200 g. Selection figures for 53224: the C0/C ratio is 3.07, Pu 11.8 kN is about 9 % of C, and the catalogue mass works out to roughly 27 g per millimetre of bore; the printed minimum-load factor is A 1. Static-first selection data: 390 kN C0 spread across the 40.8 mm stack gives 9.6 kN of static rating per height millimetre, and the 3200 g mass/C0 ratio is about 8 g per static kN — crane-hook and screw positions are normally sized on these two figures. Washer-stack proportions: the U 224 seat washer adds 5.2 mm to the 40.8 mm bearing height for a mounted H1 of 46 mm, while the 25.0 mm radial section against 120 mm bore (section/bore ≈ 0.21) identifies the envelope. Mass and section check: 3200 g inside the 120×170×40.8 mm outline leaves a 25.0 mm radial section, and the 390 kN static rating is 3.07× the dynamic rating — plan static safety and minimum preload against those figures. Washer-annulus check: the π/4·(D²−d²) contact annulus of 53224 covers about 11,388 mm², distributing C0 390 kN over a mean track circle of π·dm ≈ 456 mm. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53224 and U 224 are two order numbers shipping as two articles; the installed 46 mm H1 rather than 40.8 mm H is the dimension the housing drawing must carry.", "applications": [ "offshore deck-machinery seats", "heavy dredge and excavator pivot thrusts", "ship-lift and gate winch drums" ], "failure_modes": [ "pitting on one track sector from a perpetually eccentric thrust line", "thermal smearing after the loose housing washer is clamped solid and cannot slide with growth", "edge loading on the ball set when the U seat washer is fitted with its concave face reversed", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Minimum axial load still applies with factor A 1: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "The shaft washer remains the tight, ground-bore component on the 120 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 224 into the register.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53224 as the single sphered pressed steel execution; other order numbers of the 53224 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 224 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53224?", "a": "The catalogue envelope is 120×170×40.8 mm plus the 5.2 mm the U 224 seat washer adds to reach H1 46 mm, mass 3200 g; ratings C 127 kN / C0 390 kN / Pu 11.8 kN, reference speed 1,500 r/min (thermal) and limiting speed 2,200 r/min (mechanical)." }, { "q": "What does the designation 53224 mean?", "a": "53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 24: bore 120 mm (code 24 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Is the U 224 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53224 and U 224 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." }, { "q": "Is 53224 bidirectional?", "a": "No, the 53-series is single-direction; for reversing thrust with the same self-aligning feature use the 54-series double-direction execution, which needs two U seat washers." } ], "cross_ref": [ { "equiv_sku": "53224", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53224", "53224 + U 224" ], "locale_variants": {} }, { "sku": "53324-M", "brand": "SKF", "manufacturer_designation": "53324 M", "series": "53300-series", "type": "thrust_ball", "d_mm": 120, "D_mm": 210, "B_mm": 74.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 325, "static_load_kN": 980, "fatigue_load_limit_kN": 28.5, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1400, "max_rpm": 1400, "weight_g": 12500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "53324 M is SKF's 120 mm-bore single-direction thrust ball bearing in the 53300 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 120×210×74.1 mm U 324 seat washer companion included in the mounted H1 dimension. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 24 encode the bore as 120 mm (code 24 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 120×210×74.1 mm (4.724×8.268×2.917 in), 45.0 mm radial section, C 325 kN, C0 980 kN, Pu 28.5 kN. Mounted height H1 80 mm includes the U 324 seat washer; the bearing alone is 74.1 mm high. reference speed 1,000 r/min (thermal) and limiting speed 1,400 r/min (mechanical), catalogue mass 12500 g. Stack/annulus proportions: the 74.1 mm axial stack over the 23,326 mm² washer annulus gives 3.18 mm of height per annular square millimetre ×10⁻³, and at 12500 g the bearing holds about 78.4 kN of C0 per kilogram. Selection figures for 53324 M: the C0/C ratio is 3.02, Pu 28.5 kN is about 9 % of C, and the catalogue mass works out to roughly 104 g per millimetre of bore; the printed minimum-load factor is A 5. Sizing arithmetic on the 120 mm bore: 325 kN C over the 45.0 mm radial section gives 7.2 kN per section millimetre, and the 74.1 mm stack height is 1.65× that section — proportions typical of a 53300 thrust section. Bore-to-OD planning: OD 210 over bore 120 is a 1.75× step for this size, and the 74.1 mm height gives a bore/height ratio of 1.62; use these ratios when the housing recess around the 120 mm shaft is the first constraint. Speed planning separates the two ceilings mechanically: the pressed brass cage and balls tolerate 1,400 r/min while thermal balance under catalogue load sets the 1,000 r/min reference; at dm ≈ 165.0 mm the corresponding dn is approximately 231k mm·r/min. Heavy sphered-execution note: this M order number combines the machined brass ball-centred cage with the sphered housing washer and its U seat washer; it is the large-bore answer for hook blocks and pivots whose fabricated structure deflects — verify the spherical pair swivels freely under a light preload before the working load goes on. Under 980 kN static load the spherical interface of 53324 M must stay lubricated with a grease that does not separate at rest; a dry sphered contact under hook-block shock frets even though the ball tracks remain unworn.", "applications": [ "offshore deck-machinery seats", "heavy dredge and excavator pivot thrusts", "ship-lift and gate winch drums" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "brinell marks on the shaft-washer track from a static thrust shock beyond the C0 rating", "total loss of the aligning function after paint, scale or abrasive dust fills the sphered contact", "fretting between the sphered washer and U seat washer when the spherical interface runs dry under oscillation", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "Replacement orders must list both 53324 M and U 324: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 980 kN static-rated set.", "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 324 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "Minimum axial load still applies with factor A 5: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "Ordering discipline for 53324: the catalogue page quotes 53324 M plus U 324 and its 325/980 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53324-M?", "a": "53324 M measures 120 mm bore × 210 mm OD × 74.1 mm bearing height (4.724 × 8.268 × 2.917 in), or 80 mm mounted H1 including the U 324 seat washer, mass about 12500 g. SKF 17000 ratings: C 325 kN, C0 980 kN, Pu 28.5 kN, reference speed 1,000 r/min (thermal) and limiting speed 1,400 r/min (mechanical)." }, { "q": "What does the designation 53324 M mean?", "a": "in the 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 24 encode the bore as 120 mm (code 24 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Can I run the 53-series bearing without the U washer on a flat face?", "a": "No — that makes point contact between the sphered back and the register, gouging the housing and tilting the ball set under load. If no misalignment exists, use the cheaper flat-seat 51-series bearing of the corresponding section instead." }, { "q": "How much misalignment can 53324-M accommodate?", "a": "The spherical seat accommodates initial STATIC misalignment between shaft and housing at mounting; it is not designed for continuous oscillation or dynamic shaft deflection, and it does not add radial capacity — the load remains purely axial." } ], "cross_ref": [ { "equiv_sku": "53324", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53324-M", "53324 M", "53324 M + U 324" ], "locale_variants": {} }, { "sku": "53226", "brand": "SKF", "manufacturer_designation": "53226", "series": "53200-series", "type": "thrust_ball", "d_mm": 130, "D_mm": 190, "B_mm": 47.9, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 186, "static_load_kN": 585, "fatigue_load_limit_kN": 17, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 4850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 53200 series order number 53226 is a SKF single-direction thrust ball bearing for a 130 mm seat, built to ISO 104, with a sphered housing washer paired to a U seat washer, 130×190×47.9 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 26 decodes to 130 mm (code 26 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 130×190×47.9 mm (5.118×7.48×1.886 in), 30.0 mm radial section, C 186 kN, C0 585 kN, Pu 17 kN. Mounted height H1 53 mm includes the U 226 seat washer; the bearing alone is 47.9 mm high. reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical), catalogue mass 4850 g. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 1,800 r/min while thermal balance under catalogue load sets the 1,300 r/min reference; at dm ≈ 160.0 mm the corresponding dn is approximately 288k mm·r/min. Selection figures for 53226: the C0/C ratio is 3.15, Pu 17 kN is about 9 % of C, and the catalogue mass works out to roughly 37 g per millimetre of bore; the printed minimum-load factor is A 1.8. Bore-to-OD planning: OD 190 over bore 130 is a 1.46× step for this size, and the 47.9 mm height gives a bore/height ratio of 2.71; use these ratios when the housing recess around the 130 mm shaft is the first constraint. Capacity density: 186 kN C from 4.850 kg of bearing steel gives about 38.4 kN per kilogram; static density is correspondingly 120.6 kN/kg at C0 585 kN. Track-circle loading: per millimetre of mean track circumference the 186 kN dynamic rating corresponds to roughly 0.37 kN/mm of π·dm track, a useful comparison against the other dimension series of the 130 mm bore. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. Procurement reminder for this specific page: 53226 and U 226 are two order numbers shipping as two articles; the installed 53 mm H1 rather than 47.9 mm H is the dimension the housing drawing must carry.", "applications": [ "ladle and slag-pot hooks in steelworks", "ship-lift and gate winch drums", "offshore deck-machinery seats" ], "failure_modes": [ "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "pitting on one track sector from a perpetually eccentric thrust line", "corrosion lock of the spherical pair during long outdoor idleness with no preservative grease", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Replacement orders must list both 53226 and U 226: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 585 kN static-rated set.", "Dimension the housing to the 53 mm mounted height H1 (bearing plus U 226), not the 47.9 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.", "The shaft washer remains the tight, ground-bore component on the 130 mm shaft; the sphered part is the HOUSING washer, and the U seat washer is the loose flat-backed part — the fitting order is shaft washer and cage set first, then housing washer and U 226 into the register.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53226 as the single sphered pressed steel execution; other order numbers of the 53226 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 226 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53226?", "a": "Boundary dimensions to ISO 104: bore 130 mm, OD 190 mm, height 47.9 mm (H1 53 mm installed with the U 226 seat washer); weight 4850 g. Load figures from SKF 17000: dynamic 186 kN, static 585 kN, fatigue limit 17 kN; reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical)." }, { "q": "What does the designation 53226 mean?", "a": "the 3 in 53xxx replaces the flat-seat 1: it still denotes one load direction, but the housing washer is sphered for pairing with a U seat washer, and the following digit 2–4 ranks the section. bore code 26 decodes to 130 mm (code 26 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "What is the difference between H and H1?", "a": "H 47.9 mm is the height of the bearing itself; H1 53 mm is the installed height including the U 226 seat washer. Housing recesses and cover stacks must be drawn to H1, not H." }, { "q": "Why does 53226 need a U 226 seat washer?", "a": "The housing washer of 53226 has a sphered back face. The U 226 seat washer presents a matching concave face plus a flat housing face, and without it the convex washer contacts the register at a single point; the pair is what gives the bearing its initial-misalignment capacity." } ], "cross_ref": [ { "equiv_sku": "53226", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53226", "53226 + U 226" ], "locale_variants": {} }, { "sku": "53228", "brand": "SKF", "manufacturer_designation": "53228", "series": "53200-series", "type": "thrust_ball", "d_mm": 140, "D_mm": 200, "B_mm": 48.6, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 190, "static_load_kN": 620, "fatigue_load_limit_kN": 17.6, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 5450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 53228 is an ISO 104 single-direction thrust ball bearing, 140 mm bore and 200 mm OD, with a sphered housing washer and U seat washer, standing 48.6 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 28: bore 140 mm (code 28 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 140×200×48.6 mm (5.512×7.874×1.913 in), 30.0 mm radial section, C 190 kN, C0 620 kN, Pu 17.6 kN. Mounted height H1 55 mm includes the U 228 seat washer; the bearing alone is 48.6 mm high. reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical), catalogue mass 5450 g. Minimum-load arithmetic: with dm ≈ 170.0 mm and factor A 2, Fam ≈ A·(n·dm/1000)² at the 1,300 r/min reference speed is about 97.7 kN for 53228; below that preload the balls skid and smear the tracks. Washer-annulus check: the π/4·(D²−d²) contact annulus of 53228 covers about 16,022 mm², distributing C0 620 kN over a mean track circle of π·dm ≈ 534 mm. Mass and section check: 5450 g inside the 140×200×48.6 mm outline leaves a 30.0 mm radial section, and the 620 kN static rating is 3.26× the dynamic rating — plan static safety and minimum preload against those figures. Sizing arithmetic on the 140 mm bore: 190 kN C over the 30.0 mm radial section gives 6.3 kN per section millimetre, and the 48.6 mm stack height is 1.62× that section — proportions typical of a 53200 thrust section. Washer-stack proportions: the U 228 seat washer adds 6.4 mm to the 48.6 mm bearing height for a mounted H1 of 55 mm, while the 30.0 mm radial section against 140 mm bore (section/bore ≈ 0.21) identifies the envelope. Sphered-seating order-number note: the convex back face of the housing washer is finish-ground spherical and is delivered to mate with the separately ordered U seat washer, which presents a flat face to the housing and a concave face to the washer; together they accommodate initial static misalignment, but the pair must be kept clean, greased at the spherical interface and never replaced by a washer-on-flat-steel makeshift. The aligning angle is set by how far the sphered back of the 200 mm washer can tilt inside the U 228 seat; check the actual tilt allowance in the mounting drawing, since the 6.4 mm washer thickness step does not by itself quantify it.", "applications": [ "ladle and slag-pot hooks in steelworks", "offshore deck-machinery seats", "ship-lift and gate winch drums" ], "failure_modes": [ "ball-set launch and loss when the separable bearing is lifted out of the housing without retaining the cage", "edge loading across the ball set when the housing shoulder is not square to the shaft axis", "point-contact destruction of the housing register when a sphered washer is operated directly on a flat face without its U seat washer", "point-contact gouging of the housing face when the sphered washer is run without its U seat washer", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "track rust staining from condensate during long idle periods in humid plant air" ], "pitfalls": [ "Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 228 locks the aligning function and frets under load; re-grease the contact at every overhaul.", "The spherical seat accommodates INITIAL static misalignment between shaft and housing; it is not a swivel for continuous oscillation, and the bearing still carries pure axial load with no radial capacity.", "Dimension the housing to the 55 mm mounted height H1 (bearing plus U 228), not the 48.6 mm bearing height H — confusing the two is a recurring drawing error for the 53-series.", "Minimum axial load still applies with factor A 2: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 53228 as the single sphered pressed steel execution; other order numbers of the 53228 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 228 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 53228?", "a": "The catalogue envelope is 140×200×48.6 mm plus the 6.4 mm the U 228 seat washer adds to reach H1 55 mm, mass 5450 g; ratings C 190 kN / C0 620 kN / Pu 17.6 kN, reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical)." }, { "q": "What does the designation 53228 mean?", "a": "53xxx reads as 5 (thrust ball), 3 (single direction with a sphered housing washer), a 2–4 section digit and the bore code; the U seat washer companion carries the matching three-digit number. reading the ending 28: bore 140 mm (code 28 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 3 = single direction with sphered seating surface." }, { "q": "Is the U 228 seat washer supplied in the box?", "a": "The U seat washer is a separate order number: 53228 and U 228 are specified independently, so quote both on the purchase order — a sphered bearing without its matched seat cannot be installed correctly." }, { "q": "Is 53228 bidirectional?", "a": "No, the 53-series is single-direction; for reversing thrust with the same self-aligning feature use the 54-series double-direction execution, which needs two U seat washers." } ], "cross_ref": [ { "equiv_sku": "53228", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53228", "53228 + U 228" ], "locale_variants": {} }, { "sku": "52202", "brand": "SKF", "manufacturer_designation": "52202", "series": "52200-series", "type": "thrust_ball", "d_mm": 10, "D_mm": 32, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 15.9, "static_load_kN": 25, "fatigue_load_limit_kN": 0.915, "reference_speed_rpm": 5300, "limiting_speed_rpm": 7500, "max_rpm": 7500, "weight_g": 81, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "52202 is SKF's 10 mm-bore double-direction thrust ball bearing in the 52200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 10×32×22 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 10 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 10×32×22 mm (0.394×1.26×0.866 in), 11.0 mm radial section, C 15.9 kN, C0 25 kN, Pu 0.915 kN. reference speed 5,300 r/min (thermal) and limiting speed 7,500 r/min (mechanical), catalogue mass 81 g. Light-load floor: Pu = 0.915 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52202; the number is 6 % of the 15.9 kN dynamic rating. Envelope economics: the 22 mm axial height over a 11.0 mm radial section yields 0.7 kN of dynamic capacity per height millimetre, and the bearing weighs 81 g for 15.9 kN C — about 5 g per rated kN. Speed band width for this size is 2,200 r/min between reference and limiting (1.42× ratio); lubrication, preload and heat removal decide where inside that band 52202 can actually run. Minimum-load arithmetic: with dm ≈ 21.0 mm and factor A 0.0038, Fam ≈ A·(n·dm/1000)² at the 5,300 r/min reference speed is about 47 N for 52202; below that preload the balls skid and smear the tracks. Bore-to-OD planning: OD 32 over bore 10 is a 3.20× step for this size, and the 22 mm height gives a bore/height ratio of 0.45; use these ratios when the housing recess around the 10 mm shaft is the first constraint. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52202 is done separately per direction: if duty applies 15.9 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "small gear-selector and detent mechanisms", "reversing screw and cam spindles", "bidirectional thrust on small vertical shafts" ], "failure_modes": [ "ball skidding on the momentarily unloaded side during rapid thrust reversal below the minimum load", "cage-set loss during handling because the five components separate as soon as the unit leaves the recess", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 7,500 r/min even a small thermal thrust preload smears the hottest track.", "Service both cage sets together: replacing only the noisy side while leaving the worn 25 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 22 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "Do not replace a 52202 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 10×32 mm bore and OD.", "The 15.9/25 kN figures belong to 52202 specifically (the double flat pressed steel execution of 52202); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52202?", "a": "52202 measures 10 mm bore × 32 mm OD × 22 mm bearing height (0.394 × 1.26 × 0.866 in), mass about 81 g. SKF 17000 ratings: C 15.9 kN, C0 25 kN, Pu 0.915 kN, reference speed 5,300 r/min (thermal) and limiting speed 7,500 r/min (mechanical)." }, { "q": "What does the designation 52202 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 10 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "How is the double-direction 52202 constructed?", "a": "One central shaft washer with tracks on both faces and a ground bore, two housing washers facing outwards and two independent ball-cage assemblies — all supplied as one 10×32×22 mm unit locating the shaft axially in both directions." }, { "q": "When should I choose 52-series flat instead of 54-series sphered?", "a": "Choose the flat 52-series when the housing register can be machined square to the shaft; choose the 54-series with two U seat washers when initial misalignment has to be accommodated on fabricated or less rigid structures." } ], "cross_ref": [ { "equiv_sku": "52202", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52202" ], "locale_variants": {} }, { "sku": "52204", "brand": "SKF", "manufacturer_designation": "52204", "series": "52200-series", "type": "thrust_ball", "d_mm": 15, "D_mm": 40, "B_mm": 26, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 21.2, "static_load_kN": 37.5, "fatigue_load_limit_kN": 1.4, "reference_speed_rpm": 4300, "limiting_speed_rpm": 6000, "max_rpm": 6000, "weight_g": 150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "52204 is SKF's 15 mm-bore double-direction thrust ball bearing in the 52200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 15×40×26 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 15 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 15×40×26 mm (0.591×1.575×1.024 in), 12.5 mm radial section, C 21.2 kN, C0 37.5 kN, Pu 1.4 kN. reference speed 4,300 r/min (thermal) and limiting speed 6,000 r/min (mechanical), catalogue mass 150 g. Stack/annulus proportions: the 26 mm axial stack over the 1,080 mm² washer annulus gives 24.07 mm of height per annular square millimetre ×10⁻³, and at 150 g the bearing holds about 250.0 kN of C0 per kilogram. Washer-annulus check: the π/4·(D²−d²) contact annulus of 52204 covers about 1,080 mm², distributing C0 37.5 kN over a mean track circle of π·dm ≈ 86 mm. Minimum-load arithmetic: with dm ≈ 27.5 mm and factor A 0.0085, Fam ≈ A·(n·dm/1000)² at the 4,300 r/min reference speed is about 119 N for 52204; below that preload the balls skid and smear the tracks. Section proportions: the 12.5 mm radial section compares with 15 mm of bore (section/bore ≈ 0.83) and the 26 mm height is 2.08× that section — the proportions that identify the 52200 envelope at a glance. Speed band width for this size is 1,700 r/min between reference and limiting (1.40× ratio); lubrication, preload and heat removal decide where inside that band 52204 can actually run. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52204 is done separately per direction: if duty applies 21.2 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "office-machine reversal pivots", "bidirectional thrust on small vertical shafts", "reversing screw and cam spindles" ], "failure_modes": [ "cage-set loss during handling because the five components separate as soon as the unit leaves the recess", "differential wear when one cage set loses lubrication first on a vertical mounting", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52200 unit has no alignment capacity.", "Do not replace a 52204 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 15×40 mm bore and OD.", "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 6,000 r/min even a small thermal thrust preload smears the hottest track.", "The double-direction 52204 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 15 mm shaft axially in both directions instead of a mirrored pair.", "The 21.2/37.5 kN figures belong to 52204 specifically (the double flat pressed steel execution of 52204); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52204?", "a": "52204 measures 15 mm bore × 40 mm OD × 26 mm bearing height (0.591 × 1.575 × 1.024 in), mass about 150 g. SKF 17000 ratings: C 21.2 kN, C0 37.5 kN, Pu 1.4 kN, reference speed 4,300 r/min (thermal) and limiting speed 6,000 r/min (mechanical)." }, { "q": "What does the designation 52204 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 15 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "Can it replace two single-direction 51-series bearings?", "a": "It replaces a mirrored pair functionally — one fit, one housing bore, factory-matched geometry — but its 26 mm height is not twice the single-bearing height and seat details differ, so the housing and cover must be re-drawn rather than swapped in place." }, { "q": "How is a vertical double-direction 52204 lubricated and retained?", "a": "Use an oil bath reaching the lower track plus a feed or oil level that serves the upper cage set, or a coherent heavy-base grease; positively retain both loose housing washers because gravity loads the upper stack differently at standstill." } ], "cross_ref": [ { "equiv_sku": "52204", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52204" ], "locale_variants": {} }, { "sku": "52205", "brand": "SKF", "manufacturer_designation": "52205", "series": "52200-series", "type": "thrust_ball", "d_mm": 20, "D_mm": 47, "B_mm": 28, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 26.5, "static_load_kN": 50, "fatigue_load_limit_kN": 1.86, "reference_speed_rpm": 3800, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 220, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 52200 series order number 52205 is a SKF double-direction thrust ball bearing for a 20 mm seat, built to ISO 104, with a flat housing seating surface, 20×47×28 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 20 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 20×47×28 mm (0.787×1.85×1.102 in), 13.5 mm radial section, C 26.5 kN, C0 50 kN, Pu 1.86 kN. reference speed 3,800 r/min (thermal) and limiting speed 5,300 r/min (mechanical), catalogue mass 220 g. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 5,300 r/min while thermal balance under catalogue load sets the 3,800 r/min reference; at dm ≈ 33.5 mm the corresponding dn is approximately 178k mm·r/min. Light-load floor: Pu = 1.86 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52205; the number is 7 % of the 26.5 kN dynamic rating. Load balance: C0 50 kN against C 26.5 kN gives a 1.89 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 1.86 kN enters the adjusted-life check. Capacity density: 26.5 kN C from 0.220 kg of bearing steel gives about 120.5 kN per kilogram; static density is correspondingly 227.3 kN/kg at C0 50 kN. Pitch-diameter arithmetic: dm = (20+47)/2 = 33.5 mm; at the 5,300 r/min limiting speed that corresponds to roughly 178k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52205 is done separately per direction: if duty applies 26.5 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "office-machine reversal pivots", "reversing screw and cam spindles", "bidirectional thrust on small vertical shafts" ], "failure_modes": [ "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "cover-induced thrust preload when the end cover is torqued solid instead of leaving the catalogue axial freedom", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Do not replace a 52205 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 20×47 mm bore and OD.", "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 5,300 r/min even a small thermal thrust preload smears the hottest track.", "The double-direction 52205 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 20 mm shaft axially in both directions instead of a mirrored pair.", "The central shaft washer takes the interference fit on the 20 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52205 as the double flat pressed steel execution; other order numbers of the 52205 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52205?", "a": "Boundary dimensions to ISO 104: bore 20 mm, OD 47 mm, height 28 mm; weight 220 g. Load figures from SKF 17000: dynamic 26.5 kN, static 50 kN, fatigue limit 1.86 kN; reference speed 3,800 r/min (thermal) and limiting speed 5,300 r/min (mechanical)." }, { "q": "What does the designation 52205 mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 20 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "How is the double-direction 52205 constructed?", "a": "One central shaft washer with tracks on both faces and a ground bore, two housing washers facing outwards and two independent ball-cage assemblies — all supplied as one 20×47×28 mm unit locating the shaft axially in both directions." }, { "q": "When should I choose 52-series flat instead of 54-series sphered?", "a": "Choose the flat 52-series when the housing register can be machined square to the shaft; choose the 54-series with two U seat washers when initial misalignment has to be accommodated on fabricated or less rigid structures." } ], "cross_ref": [ { "equiv_sku": "52205", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52205" ], "locale_variants": {} }, { "sku": "52305", "brand": "SKF", "manufacturer_designation": "52305", "series": "52300-series", "type": "thrust_ball", "d_mm": 20, "D_mm": 52, "B_mm": 34, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 34.5, "static_load_kN": 60, "fatigue_load_limit_kN": 2.24, "reference_speed_rpm": 3200, "limiting_speed_rpm": 4500, "max_rpm": 4500, "weight_g": 330, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 52300 series order number 52305 is a SKF double-direction thrust ball bearing for a 20 mm seat, built to ISO 104, with a flat housing seating surface, 20×52×34 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 20 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 20×52×34 mm (0.787×2.047×1.339 in), 16.0 mm radial section, C 34.5 kN, C0 60 kN, Pu 2.24 kN. reference speed 3,200 r/min (thermal) and limiting speed 4,500 r/min (mechanical), catalogue mass 330 g. Section proportions: the 16.0 mm radial section compares with 20 mm of bore (section/bore ≈ 0.80) and the 34 mm height is 2.13× that section — the proportions that identify the 52300 envelope at a glance. Static-first selection data: 60 kN C0 spread across the 34 mm stack gives 1.8 kN of static rating per height millimetre, and the 330 g mass/C0 ratio is about 6 g per static kN — crane-hook and screw positions are normally sized on these two figures. Imperial cross-check for procurement drawings: 0.787 in bore, 2.047 in OD, 1.339 in height, and the 330 g catalogue mass converts to 0.330 kg (11.6 oz). Capacity density: 34.5 kN C from 0.330 kg of bearing steel gives about 104.5 kN per kilogram; static density is correspondingly 181.8 kN/kg at C0 60 kN. Load balance: C0 60 kN against C 34.5 kN gives a 1.74 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 2.24 kN enters the adjusted-life check. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 20 mm bore and 34 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 52 mm housing washers must remain free to slide during thermal movement.", "applications": [ "two-direction clamping heads", "reversing screw and cam spindles", "bidirectional thrust on small vertical shafts" ], "failure_modes": [ "cover-induced thrust preload when the end cover is torqued solid instead of leaving the catalogue axial freedom", "thermal lock-up when differential expansion removes the end play of the tighter-loaded side", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "raceway indentation from driving the bearing home through the ball set rather than the washer face" ], "pitfalls": [ "Service both cage sets together: replacing only the noisy side while leaving the worn 60 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 34 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 4,500 r/min even a small thermal thrust preload smears the hottest track.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52300 unit has no alignment capacity.", "Ordering discipline for 52305: the catalogue page quotes 52305 and its 34.5/60 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52305?", "a": "Boundary dimensions to ISO 104: bore 20 mm, OD 52 mm, height 34 mm; weight 330 g. Load figures from SKF 17000: dynamic 34.5 kN, static 60 kN, fatigue limit 2.24 kN; reference speed 3,200 r/min (thermal) and limiting speed 4,500 r/min (mechanical)." }, { "q": "What does the designation 52305 mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 20 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "How is the double-direction 52305 constructed?", "a": "One central shaft washer with tracks on both faces and a ground bore, two housing washers facing outwards and two independent ball-cage assemblies — all supplied as one 20×52×34 mm unit locating the shaft axially in both directions." }, { "q": "When should I choose 52-series flat instead of 54-series sphered?", "a": "Choose the flat 52-series when the housing register can be machined square to the shaft; choose the 54-series with two U seat washers when initial misalignment has to be accommodated on fabricated or less rigid structures." } ], "cross_ref": [ { "equiv_sku": "52305", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52305" ], "locale_variants": {} }, { "sku": "52406", "brand": "SKF", "manufacturer_designation": "52406", "series": "52400-series", "type": "thrust_ball", "d_mm": 20, "D_mm": 70, "B_mm": 52, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 70.2, "static_load_kN": 122, "fatigue_load_limit_kN": 4.5, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 1000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "52406 is SKF's 20 mm-bore double-direction thrust ball bearing in the 52400 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 20×70×52 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 20 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 20×70×52 mm (0.787×2.756×2.047 in), 25.0 mm radial section, C 70.2 kN, C0 122 kN, Pu 4.5 kN. reference speed 2,200 r/min (thermal) and limiting speed 3,200 r/min (mechanical), catalogue mass 1000 g. Envelope economics: the 52 mm axial height over a 25.0 mm radial section yields 1.4 kN of dynamic capacity per height millimetre, and the bearing weighs 1000 g for 70.2 kN C — about 14 g per rated kN. At the printed limiting speed of 3,200 r/min the mean pitch diameter dm ≈ 45.0 mm implies a dn value around 144k mm·r/min; the 2,200 r/min reference speed is the thermal-planning value under catalogue load. Speed band width for this size is 1,000 r/min between reference and limiting (1.45× ratio); lubrication, preload and heat removal decide where inside that band 52406 can actually run. Section proportions: the 25.0 mm radial section compares with 20 mm of bore (section/bore ≈ 1.25) and the 52 mm height is 2.08× that section — the proportions that identify the 52400 envelope at a glance. Light-load floor: Pu = 4.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52406; the number is 6 % of the 70.2 kN dynamic rating. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 20 mm bore and 52 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 70 mm housing washers must remain free to slide during thermal movement.", "applications": [ "office-machine reversal pivots", "reversing screw and cam spindles", "two-direction clamping heads" ], "failure_modes": [ "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "ball skidding on the momentarily unloaded side during rapid thrust reversal below the minimum load", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Service both cage sets together: replacing only the noisy side while leaving the worn 122 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 52 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "Each direction independently needs the minimum axial load (factor A 0.097): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52400 unit has no alignment capacity.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52406 as the double flat pressed steel execution; other order numbers of the 52406 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52406?", "a": "52406 measures 20 mm bore × 70 mm OD × 52 mm bearing height (0.787 × 2.756 × 2.047 in), mass about 1000 g. SKF 17000 ratings: C 70.2 kN, C0 122 kN, Pu 4.5 kN, reference speed 2,200 r/min (thermal) and limiting speed 3,200 r/min (mechanical)." }, { "q": "What does the designation 52406 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 20 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "Which fits and retention does 52406 need?", "a": "The central shaft washer takes an interference fit on the 20 mm shaft; both housing washers run loose in their registers and must be positively retained, especially on vertical shafts, where the upper washer and its cage set also need lubricant retained." }, { "q": "What static check governs crane-hook duty for 52406?", "a": "Hook and screw positions are usually sized on C0 (122 kN here) with the application's static safety factor against peak stationary or shock thrust, not on the 70.2 kN L10 figure — reversal frequency then decides whether the 52-series geometry is acceptable." } ], "cross_ref": [ { "equiv_sku": "52406", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52406" ], "locale_variants": {} }, { "sku": "52206", "brand": "SKF", "manufacturer_designation": "52206", "series": "52200-series", "type": "thrust_ball", "d_mm": 25, "D_mm": 52, "B_mm": 29, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.1, "static_load_kN": 51, "fatigue_load_limit_kN": 1.86, "reference_speed_rpm": 3600, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "52206 is SKF's 25 mm-bore double-direction thrust ball bearing in the 52200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 25×52×29 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 25 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 25×52×29 mm (0.984×2.047×1.142 in), 13.5 mm radial section, C 25.1 kN, C0 51 kN, Pu 1.86 kN. reference speed 3,600 r/min (thermal) and limiting speed 5,000 r/min (mechanical), catalogue mass 250 g. Speed band width for this size is 1,400 r/min between reference and limiting (1.39× ratio); lubrication, preload and heat removal decide where inside that band 52206 can actually run. Speed-ratio note for this exact unit: the reference speed is 3,600 r/min against a 5,000 r/min limiting speed, a reference-to-limit ratio of 0.72. Light-load floor: Pu = 1.86 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52206; the number is 7 % of the 25.1 kN dynamic rating. Pitch-diameter arithmetic: dm = (25+52)/2 = 38.5 mm; at the 5,000 r/min limiting speed that corresponds to roughly 193k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Imperial cross-check for procurement drawings: 0.984 in bore, 2.047 in OD, 1.142 in height, and the 250 g catalogue mass converts to 0.250 kg (8.8 oz). Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52206 is done separately per direction: if duty applies 25.1 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "machine-tool lead screws and selector shafts", "elevator machinery thrust positions", "steering and reversing linkages" ], "failure_modes": [ "ball skidding on the momentarily unloaded side during rapid thrust reversal below the minimum load", "differential wear when one cage set loses lubrication first on a vertical mounting", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 5,000 r/min even a small thermal thrust preload smears the hottest track.", "Service both cage sets together: replacing only the noisy side while leaving the worn 51 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52200 unit has no alignment capacity.", "Do not replace a 52206 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 25×52 mm bore and OD.", "The 25.1/51 kN figures belong to 52206 specifically (the double flat pressed steel execution of 52206); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52206?", "a": "52206 measures 25 mm bore × 52 mm OD × 29 mm bearing height (0.984 × 2.047 × 1.142 in), mass about 250 g. SKF 17000 ratings: C 25.1 kN, C0 51 kN, Pu 1.86 kN, reference speed 3,600 r/min (thermal) and limiting speed 5,000 r/min (mechanical)." }, { "q": "What does the designation 52206 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 25 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "What minimum axial load applies to a double-direction bearing?", "a": "The Fam ≈ A·(n·dm/1000)² rule (factor A 0.013) applies to EACH direction: the momentarily unloaded side during slow reversal is the one that skids, so preload or balanced loading must keep both ball sets seated." }, { "q": "How is the double-direction 52206 constructed?", "a": "One central shaft washer with tracks on both faces and a ground bore, two housing washers facing outwards and two independent ball-cage assemblies — all supplied as one 25×52×29 mm unit locating the shaft axially in both directions." } ], "cross_ref": [ { "equiv_sku": "52206", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52206" ], "locale_variants": {} }, { "sku": "52306", "brand": "SKF", "manufacturer_designation": "52306", "series": "52300-series", "type": "thrust_ball", "d_mm": 25, "D_mm": 60, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.8, "static_load_kN": 65.5, "fatigue_load_limit_kN": 2.4, "reference_speed_rpm": 2800, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 470, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "52306 is SKF's 25 mm-bore double-direction thrust ball bearing in the 52300 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 25×60×38 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 25 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 25×60×38 mm (0.984×2.362×1.496 in), 17.5 mm radial section, C 35.8 kN, C0 65.5 kN, Pu 2.4 kN. reference speed 2,800 r/min (thermal) and limiting speed 4,000 r/min (mechanical), catalogue mass 470 g. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.026 at the 4,000 r/min limiting speed raises the required axial preload to about 751 N; the reference-speed value 368 N is the thermal design point. Imperial cross-check for procurement drawings: 0.984 in bore, 2.362 in OD, 1.496 in height, and the 470 g catalogue mass converts to 0.470 kg (16.6 oz). Rating split for documentation: dynamic 35.8 kN (L10 life), static 65.5 kN (safety factor s0), fatigue limit 2.4 kN (adjusted life) — three different uses of three different numbers for 52306, none interchangeable with another. Light-load floor: Pu = 2.4 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52306; the number is 7 % of the 35.8 kN dynamic rating. Static-first selection data: 65.5 kN C0 spread across the 38 mm stack gives 1.7 kN of static rating per height millimetre, and the 470 g mass/C0 ratio is about 7 g per static kN — crane-hook and screw positions are normally sized on these two figures. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 25 mm bore and 38 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 60 mm housing washers must remain free to slide during thermal movement.", "applications": [ "reversing gearbox shafts in one compact position", "steering and reversing linkages", "elevator machinery thrust positions" ], "failure_modes": [ "thermal lock-up when differential expansion removes the end play of the tighter-loaded side", "ball skidding on the momentarily unloaded side during rapid thrust reversal below the minimum load", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 4,000 r/min even a small thermal thrust preload smears the hottest track.", "Service both cage sets together: replacing only the noisy side while leaving the worn 65.5 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Do not replace a 52306 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 25×60 mm bore and OD.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52300 unit has no alignment capacity.", "Ordering discipline for 52306: the catalogue page quotes 52306 and its 35.8/65.5 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52306?", "a": "52306 measures 25 mm bore × 60 mm OD × 38 mm bearing height (0.984 × 2.362 × 1.496 in), mass about 470 g. SKF 17000 ratings: C 35.8 kN, C0 65.5 kN, Pu 2.4 kN, reference speed 2,800 r/min (thermal) and limiting speed 4,000 r/min (mechanical)." }, { "q": "What does the designation 52306 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 25 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "Which fits and retention does 52306 need?", "a": "The central shaft washer takes an interference fit on the 25 mm shaft; both housing washers run loose in their registers and must be positively retained, especially on vertical shafts, where the upper washer and its cage set also need lubricant retained." }, { "q": "What static check governs crane-hook duty for 52306?", "a": "Hook and screw positions are usually sized on C0 (65.5 kN here) with the application's static safety factor against peak stationary or shock thrust, not on the 35.8 kN L10 figure — reversal frequency then decides whether the 52-series geometry is acceptable." } ], "cross_ref": [ { "equiv_sku": "52306", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52306" ], "locale_variants": {} }, { "sku": "52407", "brand": "SKF", "manufacturer_designation": "52407", "series": "52400-series", "type": "thrust_ball", "d_mm": 25, "D_mm": 80, "B_mm": 59, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 76.1, "static_load_kN": 137, "fatigue_load_limit_kN": 5.1, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 1450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52407 is an ISO 104 double-direction thrust ball bearing, 25 mm bore and 80 mm OD on a flat housing seat, standing 59 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52407 is 25 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 25×80×59 mm (0.984×3.15×2.323 in), 27.5 mm radial section, C 76.1 kN, C0 137 kN, Pu 5.1 kN. reference speed 2,000 r/min (thermal) and limiting speed 2,800 r/min (mechanical), catalogue mass 1450 g. At the printed limiting speed of 2,800 r/min the mean pitch diameter dm ≈ 52.5 mm implies a dn value around 147k mm·r/min; the 2,000 r/min reference speed is the thermal-planning value under catalogue load. Light-load floor: Pu = 5.1 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52407; the number is 7 % of the 76.1 kN dynamic rating. Load balance: C0 137 kN against C 76.1 kN gives a 1.80 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 5.1 kN enters the adjusted-life check. Rating split for documentation: dynamic 76.1 kN (L10 life), static 137 kN (safety factor s0), fatigue limit 5.1 kN (adjusted life) — three different uses of three different numbers for 52407, none interchangeable with another. Minimum-load arithmetic: with dm ≈ 52.5 mm and factor A 0.15, Fam ≈ A·(n·dm/1000)² at the 2,000 r/min reference speed is about 1.7 kN for 52407; below that preload the balls skid and smear the tracks. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52407 is done separately per direction: if duty applies 76.1 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "elevator machinery thrust positions", "steering and reversing linkages", "reversing gearbox shafts in one compact position" ], "failure_modes": [ "brinelling of one track pair from a static reversing shock concentrated on a single side", "track-edge spalling after the shaft washer seat is machined out of square and both rows share the tilt", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Do not replace a 52407 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 25×80 mm bore and OD.", "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 2,800 r/min even a small thermal thrust preload smears the hottest track.", "The central shaft washer takes the interference fit on the 25 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "Each direction independently needs the minimum axial load (factor A 0.15): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52407 as the double flat pressed steel execution; other order numbers of the 52407 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52407?", "a": "The catalogue envelope is 25×80×59 mm, mass 1450 g; ratings C 76.1 kN / C0 137 kN / Pu 5.1 kN, reference speed 2,000 r/min (thermal) and limiting speed 2,800 r/min (mechanical)." }, { "q": "What does the designation 52407 mean?", "a": "note the bore of 52407 is 25 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "How is a vertical double-direction 52407 lubricated and retained?", "a": "Use an oil bath reaching the lower track plus a feed or oil level that serves the upper cage set, or a coherent heavy-base grease; positively retain both loose housing washers because gravity loads the upper stack differently at standstill." }, { "q": "Which fits and retention does 52407 need?", "a": "The central shaft washer takes an interference fit on the 25 mm shaft; both housing washers run loose in their registers and must be positively retained, especially on vertical shafts, where the upper washer and its cage set also need lubricant retained." } ], "cross_ref": [ { "equiv_sku": "52407", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52407" ], "locale_variants": {} }, { "sku": "52207", "brand": "SKF", "manufacturer_designation": "52207", "series": "52200-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 62, "B_mm": 34, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 73.5, "fatigue_load_limit_kN": 2.7, "reference_speed_rpm": 3000, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 410, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 52200 series order number 52207 is a SKF double-direction thrust ball bearing for a 30 mm seat, built to ISO 104, with a flat housing seating surface, 30×62×34 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 30 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 30×62×34 mm (1.181×2.441×1.339 in), 16.0 mm radial section, C 35.1 kN, C0 73.5 kN, Pu 2.7 kN. reference speed 3,000 r/min (thermal) and limiting speed 4,300 r/min (mechanical), catalogue mass 410 g. Pitch-diameter arithmetic: dm = (30+62)/2 = 46.0 mm; at the 4,300 r/min limiting speed that corresponds to roughly 198k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Minimum-load arithmetic: with dm ≈ 46.0 mm and factor A 0.028, Fam ≈ A·(n·dm/1000)² at the 3,000 r/min reference speed is about 533 N for 52207; below that preload the balls skid and smear the tracks. Track-circle loading: per millimetre of mean track circumference the 35.1 kN dynamic rating corresponds to roughly 0.24 kN/mm of π·dm track, a useful comparison against the other dimension series of the 30 mm bore. Rating split for documentation: dynamic 35.1 kN (L10 life), static 73.5 kN (safety factor s0), fatigue limit 2.7 kN (adjusted life) — three different uses of three different numbers for 52207, none interchangeable with another. Stack/annulus proportions: the 34 mm axial stack over the 2,312 mm² washer annulus gives 14.71 mm of height per annular square millimetre ×10⁻³, and at 410 g the bearing holds about 179.3 kN of C0 per kilogram. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 30 mm bore and 34 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 62 mm housing washers must remain free to slide during thermal movement.", "applications": [ "vertical pumps with intermittent up-thrust", "elevator machinery thrust positions", "steering and reversing linkages" ], "failure_modes": [ "assembly damage when the central shaft washer is fitted reversed or the two outward-facing housing washers are swapped", "cover-induced thrust preload when the end cover is torqued solid instead of leaving the catalogue axial freedom", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "washer face scoring from swarf trapped between the loose housing washer and its register", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 4,300 r/min even a small thermal thrust preload smears the hottest track.", "Service both cage sets together: replacing only the noisy side while leaving the worn 73.5 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Do not replace a 52207 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 30×62 mm bore and OD.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52200 unit has no alignment capacity.", "Ordering discipline for 52207: the catalogue page quotes 52207 and its 35.1/73.5 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52207?", "a": "Boundary dimensions to ISO 104: bore 30 mm, OD 62 mm, height 34 mm; weight 410 g. Load figures from SKF 17000: dynamic 35.1 kN, static 73.5 kN, fatigue limit 2.7 kN; reference speed 3,000 r/min (thermal) and limiting speed 4,300 r/min (mechanical)." }, { "q": "What does the designation 52207 mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 30 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "When should I choose 52-series flat instead of 54-series sphered?", "a": "Choose the flat 52-series when the housing register can be machined square to the shaft; choose the 54-series with two U seat washers when initial misalignment has to be accommodated on fabricated or less rigid structures." }, { "q": "Can it replace two single-direction 51-series bearings?", "a": "It replaces a mirrored pair functionally — one fit, one housing bore, factory-matched geometry — but its 34 mm height is not twice the single-bearing height and seat details differ, so the housing and cover must be re-drawn rather than swapped in place." } ], "cross_ref": [ { "equiv_sku": "52207", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52207" ], "locale_variants": {} }, { "sku": "52208", "brand": "SKF", "manufacturer_designation": "52208", "series": "52200-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 68, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 44.2, "static_load_kN": 96.5, "fatigue_load_limit_kN": 3.6, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "52208 is SKF's 30 mm-bore double-direction thrust ball bearing in the 52200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 30×68×36 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 30 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 30×68×36 mm (1.181×2.677×1.417 in), 19.0 mm radial section, C 44.2 kN, C0 96.5 kN, Pu 3.6 kN. reference speed 2,800 r/min (thermal) and limiting speed 3,800 r/min (mechanical), catalogue mass 550 g. Load balance: C0 96.5 kN against C 44.2 kN gives a 2.18 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 3.6 kN enters the adjusted-life check. Selection figures for 52208: the C0/C ratio is 2.18, Pu 3.6 kN is about 8 % of C, and the catalogue mass works out to roughly 18 g per millimetre of bore; the printed minimum-load factor is A 0.058. Minimum-load arithmetic: with dm ≈ 49.0 mm and factor A 0.058, Fam ≈ A·(n·dm/1000)² at the 2,800 r/min reference speed is about 1.1 kN for 52208; below that preload the balls skid and smear the tracks. Mass and section check: 550 g inside the 30×68×36 mm outline leaves a 19.0 mm radial section, and the 96.5 kN static rating is 2.18× the dynamic rating — plan static safety and minimum preload against those figures. Bore-to-OD planning: OD 68 over bore 30 is a 2.27× step for this size, and the 36 mm height gives a bore/height ratio of 0.83; use these ratios when the housing recess around the 30 mm shaft is the first constraint. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52208 is done separately per direction: if duty applies 44.2 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "machine-tool lead screws and selector shafts", "vertical pumps with intermittent up-thrust", "elevator machinery thrust positions" ], "failure_modes": [ "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "ball skidding on the momentarily unloaded side during rapid thrust reversal below the minimum load", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "raceway indentation from driving the bearing home through the ball set rather than the washer face" ], "pitfalls": [ "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52200 unit has no alignment capacity.", "Do not replace a 52208 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 30×68 mm bore and OD.", "Each direction independently needs the minimum axial load (factor A 0.058): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "The double-direction 52208 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 30 mm shaft axially in both directions instead of a mirrored pair.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52208 as the double flat pressed steel execution; other order numbers of the 52208 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52208?", "a": "52208 measures 30 mm bore × 68 mm OD × 36 mm bearing height (1.181 × 2.677 × 1.417 in), mass about 550 g. SKF 17000 ratings: C 44.2 kN, C0 96.5 kN, Pu 3.6 kN, reference speed 2,800 r/min (thermal) and limiting speed 3,800 r/min (mechanical)." }, { "q": "What does the designation 52208 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 30 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "What static check governs crane-hook duty for 52208?", "a": "Hook and screw positions are usually sized on C0 (96.5 kN here) with the application's static safety factor against peak stationary or shock thrust, not on the 44.2 kN L10 figure — reversal frequency then decides whether the 52-series geometry is acceptable." }, { "q": "What minimum axial load applies to a double-direction bearing?", "a": "The Fam ≈ A·(n·dm/1000)² rule (factor A 0.058) applies to EACH direction: the momentarily unloaded side during slow reversal is the one that skids, so preload or balanced loading must keep both ball sets seated." } ], "cross_ref": [ { "equiv_sku": "52208", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52208" ], "locale_variants": {} }, { "sku": "52307", "brand": "SKF", "manufacturer_designation": "52307", "series": "52300-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 68, "B_mm": 44, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 49.4, "static_load_kN": 96.5, "fatigue_load_limit_kN": 3.55, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 680, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52307 is an ISO 104 double-direction thrust ball bearing, 30 mm bore and 68 mm OD on a flat housing seat, standing 44 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52307 is 30 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 30×68×44 mm (1.181×2.677×1.732 in), 19.0 mm radial section, C 49.4 kN, C0 96.5 kN, Pu 3.55 kN. reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical), catalogue mass 680 g. Selection figures for 52307: the C0/C ratio is 1.95, Pu 3.55 kN is about 7 % of C, and the catalogue mass works out to roughly 23 g per millimetre of bore; the printed minimum-load factor is A 0.048. Bore-to-OD planning: OD 68 over bore 30 is a 2.27× step for this size, and the 44 mm height gives a bore/height ratio of 0.68; use these ratios when the housing recess around the 30 mm shaft is the first constraint. At the printed limiting speed of 3,400 r/min the mean pitch diameter dm ≈ 49.0 mm implies a dn value around 167k mm·r/min; the 2,400 r/min reference speed is the thermal-planning value under catalogue load. Light-load floor: Pu = 3.55 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52307; the number is 7 % of the 49.4 kN dynamic rating. Track-circle loading: per millimetre of mean track circumference the 49.4 kN dynamic rating corresponds to roughly 0.32 kN/mm of π·dm track, a useful comparison against the other dimension series of the 30 mm bore. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 30 mm bore and 44 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 68 mm housing washers must remain free to slide during thermal movement.", "applications": [ "steering and reversing linkages", "vertical pumps with intermittent up-thrust", "machine-tool lead screws and selector shafts" ], "failure_modes": [ "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "track-edge spalling after the shaft washer seat is machined out of square and both rows share the tilt", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Do not replace a 52307 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 30×68 mm bore and OD.", "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 3,400 r/min even a small thermal thrust preload smears the hottest track.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52300 unit has no alignment capacity.", "The central shaft washer takes the interference fit on the 30 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52307 as the double flat pressed steel execution; other order numbers of the 52307 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52307?", "a": "The catalogue envelope is 30×68×44 mm, mass 680 g; ratings C 49.4 kN / C0 96.5 kN / Pu 3.55 kN, reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical)." }, { "q": "What does the designation 52307 mean?", "a": "note the bore of 52307 is 30 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "Which fits and retention does 52307 need?", "a": "The central shaft washer takes an interference fit on the 30 mm shaft; both housing washers run loose in their registers and must be positively retained, especially on vertical shafts, where the upper washer and its cage set also need lubricant retained." }, { "q": "What static check governs crane-hook duty for 52307?", "a": "Hook and screw positions are usually sized on C0 (96.5 kN here) with the application's static safety factor against peak stationary or shock thrust, not on the 49.4 kN L10 figure — reversal frequency then decides whether the 52-series geometry is acceptable." } ], "cross_ref": [ { "equiv_sku": "52307", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52307" ], "locale_variants": {} }, { "sku": "52308", "brand": "SKF", "manufacturer_designation": "52308", "series": "52300-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 78, "B_mm": 49, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 61.8, "static_load_kN": 122, "fatigue_load_limit_kN": 4.5, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 52300 series order number 52308 is a SKF double-direction thrust ball bearing for a 30 mm seat, built to ISO 104, with a flat housing seating surface, 30×78×49 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 30 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 30×78×49 mm (1.181×3.071×1.929 in), 24.0 mm radial section, C 61.8 kN, C0 122 kN, Pu 4.5 kN. reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical), catalogue mass 1050 g. Envelope economics: the 49 mm axial height over a 24.0 mm radial section yields 1.3 kN of dynamic capacity per height millimetre, and the bearing weighs 1050 g for 61.8 kN C — about 17 g per rated kN. Mass and section check: 1050 g inside the 30×78×49 mm outline leaves a 24.0 mm radial section, and the 122 kN static rating is 1.97× the dynamic rating — plan static safety and minimum preload against those figures. Rating split for documentation: dynamic 61.8 kN (L10 life), static 122 kN (safety factor s0), fatigue limit 4.5 kN (adjusted life) — three different uses of three different numbers for 52308, none interchangeable with another. Light-load floor: Pu = 4.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52308; the number is 7 % of the 61.8 kN dynamic rating. Static-first selection data: 122 kN C0 spread across the 49 mm stack gives 2.5 kN of static rating per height millimetre, and the 1050 g mass/C0 ratio is about 9 g per static kN — crane-hook and screw positions are normally sized on these two figures. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52308 is done separately per direction: if duty applies 61.8 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "vertical pumps with intermittent up-thrust", "steering and reversing linkages", "elevator machinery thrust positions" ], "failure_modes": [ "cover-induced thrust preload when the end cover is torqued solid instead of leaving the catalogue axial freedom", "thermal lock-up when differential expansion removes the end play of the tighter-loaded side", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "The double-direction 52308 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 30 mm shaft axially in both directions instead of a mirrored pair.", "Each direction independently needs the minimum axial load (factor A 0.077): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "Do not replace a 52308 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 30×78 mm bore and OD.", "The central shaft washer takes the interference fit on the 30 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "Ordering discipline for 52308: the catalogue page quotes 52308 and its 61.8/122 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52308?", "a": "Boundary dimensions to ISO 104: bore 30 mm, OD 78 mm, height 49 mm; weight 1050 g. Load figures from SKF 17000: dynamic 61.8 kN, static 122 kN, fatigue limit 4.5 kN; reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical)." }, { "q": "What does the designation 52308 mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 30 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "Which fits and retention does 52308 need?", "a": "The central shaft washer takes an interference fit on the 30 mm shaft; both housing washers run loose in their registers and must be positively retained, especially on vertical shafts, where the upper washer and its cage set also need lubricant retained." }, { "q": "What static check governs crane-hook duty for 52308?", "a": "Hook and screw positions are usually sized on C0 (122 kN here) with the application's static safety factor against peak stationary or shock thrust, not on the 61.8 kN L10 figure — reversal frequency then decides whether the 52-series geometry is acceptable." } ], "cross_ref": [ { "equiv_sku": "52308", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52308" ], "locale_variants": {} }, { "sku": "52408", "brand": "SKF", "manufacturer_designation": "52408", "series": "52400-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 90, "B_mm": 65, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 95.6, "static_load_kN": 183, "fatigue_load_limit_kN": 6.8, "reference_speed_rpm": 1800, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 2050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52408 is an ISO 104 double-direction thrust ball bearing, 30 mm bore and 90 mm OD on a flat housing seat, standing 65 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52408 is 30 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 30×90×65 mm (1.181×3.543×2.559 in), 30.0 mm radial section, C 95.6 kN, C0 183 kN, Pu 6.8 kN. reference speed 1,800 r/min (thermal) and limiting speed 2,400 r/min (mechanical), catalogue mass 2050 g. Pitch-diameter arithmetic: dm = (30+90)/2 = 60.0 mm; at the 2,400 r/min limiting speed that corresponds to roughly 144k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Track-circle loading: per millimetre of mean track circumference the 95.6 kN dynamic rating corresponds to roughly 0.51 kN/mm of π·dm track, a useful comparison against the other dimension series of the 30 mm bore. Rating split for documentation: dynamic 95.6 kN (L10 life), static 183 kN (safety factor s0), fatigue limit 6.8 kN (adjusted life) — three different uses of three different numbers for 52408, none interchangeable with another. Sizing arithmetic on the 30 mm bore: 95.6 kN C over the 30.0 mm radial section gives 3.2 kN per section millimetre, and the 65 mm stack height is 2.17× that section — proportions typical of a 52400 thrust section. Static-first selection data: 183 kN C0 spread across the 65 mm stack gives 2.8 kN of static rating per height millimetre, and the 2050 g mass/C0 ratio is about 11 g per static kN — crane-hook and screw positions are normally sized on these two figures. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52408 is done separately per direction: if duty applies 95.6 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "reversing gearbox shafts in one compact position", "machine-tool lead screws and selector shafts", "vertical pumps with intermittent up-thrust" ], "failure_modes": [ "ball skidding on the momentarily unloaded side during rapid thrust reversal below the minimum load", "track-edge spalling after the shaft washer seat is machined out of square and both rows share the tilt", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52400 unit has no alignment capacity.", "Do not replace a 52408 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 30×90 mm bore and OD.", "The double-direction 52408 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 30 mm shaft axially in both directions instead of a mirrored pair.", "Each direction independently needs the minimum axial load (factor A 0.26): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "The 95.6/183 kN figures belong to 52408 specifically (the double flat pressed steel execution of 52408); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52408?", "a": "The catalogue envelope is 30×90×65 mm, mass 2050 g; ratings C 95.6 kN / C0 183 kN / Pu 6.8 kN, reference speed 1,800 r/min (thermal) and limiting speed 2,400 r/min (mechanical)." }, { "q": "What does the designation 52408 mean?", "a": "note the bore of 52408 is 30 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "When should I choose 52-series flat instead of 54-series sphered?", "a": "Choose the flat 52-series when the housing register can be machined square to the shaft; choose the 54-series with two U seat washers when initial misalignment has to be accommodated on fabricated or less rigid structures." }, { "q": "Can it replace two single-direction 51-series bearings?", "a": "It replaces a mirrored pair functionally — one fit, one housing bore, factory-matched geometry — but its 65 mm height is not twice the single-bearing height and seat details differ, so the housing and cover must be re-drawn rather than swapped in place." } ], "cross_ref": [ { "equiv_sku": "52408", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52408" ], "locale_variants": {} }, { "sku": "52209", "brand": "SKF", "manufacturer_designation": "52209", "series": "52200-series", "type": "thrust_ball", "d_mm": 35, "D_mm": 73, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 39, "static_load_kN": 86.5, "fatigue_load_limit_kN": 3.2, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "52209 is SKF's 35 mm-bore double-direction thrust ball bearing in the 52200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 35×73×37 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 35 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 35×73×37 mm (1.378×2.874×1.457 in), 19.0 mm radial section, C 39 kN, C0 86.5 kN, Pu 3.2 kN. reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical), catalogue mass 600 g. Envelope economics: the 37 mm axial height over a 19.0 mm radial section yields 1.1 kN of dynamic capacity per height millimetre, and the bearing weighs 600 g for 39 kN C — about 15 g per rated kN. Light-load floor: Pu = 3.2 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52209; the number is 8 % of the 39 kN dynamic rating. Rating split for documentation: dynamic 39 kN (L10 life), static 86.5 kN (safety factor s0), fatigue limit 3.2 kN (adjusted life) — three different uses of three different numbers for 52209, none interchangeable with another. Selection figures for 52209: the C0/C ratio is 2.22, Pu 3.2 kN is about 8 % of C, and the catalogue mass works out to roughly 17 g per millimetre of bore; the printed minimum-load factor is A 0.038. Mass and section check: 600 g inside the 35×73×37 mm outline leaves a 19.0 mm radial section, and the 86.5 kN static rating is 2.22× the dynamic rating — plan static safety and minimum preload against those figures. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52209 is done separately per direction: if duty applies 39 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "elevator machinery thrust positions", "machine-tool lead screws and selector shafts", "vertical pumps with intermittent up-thrust" ], "failure_modes": [ "cage-set loss during handling because the five components separate as soon as the unit leaves the recess", "differential wear when one cage set loses lubrication first on a vertical mounting", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "track rust staining from condensate during long idle periods in humid plant air", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "The double-direction 52209 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 35 mm shaft axially in both directions instead of a mirrored pair.", "Each direction independently needs the minimum axial load (factor A 0.038): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "Do not replace a 52209 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 35×73 mm bore and OD.", "The central shaft washer takes the interference fit on the 35 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "The 39/86.5 kN figures belong to 52209 specifically (the double flat pressed steel execution of 52209); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52209?", "a": "52209 measures 35 mm bore × 73 mm OD × 37 mm bearing height (1.378 × 2.874 × 1.457 in), mass about 600 g. SKF 17000 ratings: C 39 kN, C0 86.5 kN, Pu 3.2 kN, reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical)." }, { "q": "What does the designation 52209 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 35 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "How is a vertical double-direction 52209 lubricated and retained?", "a": "Use an oil bath reaching the lower track plus a feed or oil level that serves the upper cage set, or a coherent heavy-base grease; positively retain both loose housing washers because gravity loads the upper stack differently at standstill." }, { "q": "Which fits and retention does 52209 need?", "a": "The central shaft washer takes an interference fit on the 35 mm shaft; both housing washers run loose in their registers and must be positively retained, especially on vertical shafts, where the upper washer and its cage set also need lubricant retained." } ], "cross_ref": [ { "equiv_sku": "52209", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52209" ], "locale_variants": {} }, { "sku": "52309", "brand": "SKF", "manufacturer_designation": "52309", "series": "52300-series", "type": "thrust_ball", "d_mm": 35, "D_mm": 85, "B_mm": 52, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 76.1, "static_load_kN": 153, "fatigue_load_limit_kN": 5.6, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 1250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52309 is an ISO 104 double-direction thrust ball bearing, 35 mm bore and 85 mm OD on a flat housing seat, standing 52 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52309 is 35 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 35×85×52 mm (1.378×3.346×2.047 in), 25.0 mm radial section, C 76.1 kN, C0 153 kN, Pu 5.6 kN. reference speed 2,000 r/min (thermal) and limiting speed 2,800 r/min (mechanical), catalogue mass 1250 g. Selection figures for 52309: the C0/C ratio is 2.01, Pu 5.6 kN is about 7 % of C, and the catalogue mass works out to roughly 36 g per millimetre of bore; the printed minimum-load factor is A 0.12. Section proportions: the 25.0 mm radial section compares with 35 mm of bore (section/bore ≈ 0.71) and the 52 mm height is 2.08× that section — the proportions that identify the 52300 envelope at a glance. Static-first selection data: 153 kN C0 spread across the 52 mm stack gives 2.9 kN of static rating per height millimetre, and the 1250 g mass/C0 ratio is about 8 g per static kN — crane-hook and screw positions are normally sized on these two figures. Minimum-load arithmetic: with dm ≈ 60.0 mm and factor A 0.12, Fam ≈ A·(n·dm/1000)² at the 2,000 r/min reference speed is about 1.7 kN for 52309; below that preload the balls skid and smear the tracks. Bore-to-OD planning: OD 85 over bore 35 is a 2.43× step for this size, and the 52 mm height gives a bore/height ratio of 0.67; use these ratios when the housing recess around the 35 mm shaft is the first constraint. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 35 mm bore and 52 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 85 mm housing washers must remain free to slide during thermal movement.", "applications": [ "elevator machinery thrust positions", "reversing gearbox shafts in one compact position", "vertical pumps with intermittent up-thrust" ], "failure_modes": [ "cover-induced thrust preload when the end cover is torqued solid instead of leaving the catalogue axial freedom", "brinelling of one track pair from a static reversing shock concentrated on a single side", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "The central shaft washer takes the interference fit on the 35 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52300 unit has no alignment capacity.", "Each direction independently needs the minimum axial load (factor A 0.12): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "Service both cage sets together: replacing only the noisy side while leaving the worn 153 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Ordering discipline for 52309: the catalogue page quotes 52309 and its 76.1/153 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52309?", "a": "The catalogue envelope is 35×85×52 mm, mass 1250 g; ratings C 76.1 kN / C0 153 kN / Pu 5.6 kN, reference speed 2,000 r/min (thermal) and limiting speed 2,800 r/min (mechanical)." }, { "q": "What does the designation 52309 mean?", "a": "note the bore of 52309 is 35 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "How is a vertical double-direction 52309 lubricated and retained?", "a": "Use an oil bath reaching the lower track plus a feed or oil level that serves the upper cage set, or a coherent heavy-base grease; positively retain both loose housing washers because gravity loads the upper stack differently at standstill." }, { "q": "Which fits and retention does 52309 need?", "a": "The central shaft washer takes an interference fit on the 35 mm shaft; both housing washers run loose in their registers and must be positively retained, especially on vertical shafts, where the upper washer and its cage set also need lubricant retained." } ], "cross_ref": [ { "equiv_sku": "52309", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52309" ], "locale_variants": {} }, { "sku": "52409", "brand": "SKF", "manufacturer_designation": "52409", "series": "52400-series", "type": "thrust_ball", "d_mm": 35, "D_mm": 100, "B_mm": 72, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 124, "static_load_kN": 240, "fatigue_load_limit_kN": 9, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 2700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "52409 is SKF's 35 mm-bore double-direction thrust ball bearing in the 52400 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 35×100×72 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 35 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 35×100×72 mm (1.378×3.937×2.835 in), 32.5 mm radial section, C 124 kN, C0 240 kN, Pu 9 kN. reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical), catalogue mass 2700 g. Track-circle loading: per millimetre of mean track circumference the 124 kN dynamic rating corresponds to roughly 0.58 kN/mm of π·dm track, a useful comparison against the other dimension series of the 35 mm bore. Speed band width for this size is 600 r/min between reference and limiting (1.38× ratio); lubrication, preload and heat removal decide where inside that band 52409 can actually run. Light-load floor: Pu = 9 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52409; the number is 7 % of the 124 kN dynamic rating. Sizing arithmetic on the 35 mm bore: 124 kN C over the 32.5 mm radial section gives 3.8 kN per section millimetre, and the 72 mm stack height is 2.22× that section — proportions typical of a 52400 thrust section. Mass and section check: 2700 g inside the 35×100×72 mm outline leaves a 32.5 mm radial section, and the 240 kN static rating is 1.94× the dynamic rating — plan static safety and minimum preload against those figures. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52409 is done separately per direction: if duty applies 124 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "machine-tool lead screws and selector shafts", "steering and reversing linkages", "elevator machinery thrust positions" ], "failure_modes": [ "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "ball skidding on the momentarily unloaded side during rapid thrust reversal below the minimum load", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "Do not replace a 52409 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 35×100 mm bore and OD.", "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 2,200 r/min even a small thermal thrust preload smears the hottest track.", "Service both cage sets together: replacing only the noisy side while leaving the worn 240 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "The central shaft washer takes the interference fit on the 35 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52409 as the double flat pressed steel execution; other order numbers of the 52409 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52409?", "a": "52409 measures 35 mm bore × 100 mm OD × 72 mm bearing height (1.378 × 3.937 × 2.835 in), mass about 2700 g. SKF 17000 ratings: C 124 kN, C0 240 kN, Pu 9 kN, reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical)." }, { "q": "What does the designation 52409 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 35 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "What static check governs crane-hook duty for 52409?", "a": "Hook and screw positions are usually sized on C0 (240 kN here) with the application's static safety factor against peak stationary or shock thrust, not on the 124 kN L10 figure — reversal frequency then decides whether the 52-series geometry is acceptable." }, { "q": "What minimum axial load applies to a double-direction bearing?", "a": "The Fam ≈ A·(n·dm/1000)² rule (factor A 0.37) applies to EACH direction: the momentarily unloaded side during slow reversal is the one that skids, so preload or balanced loading must keep both ball sets seated." } ], "cross_ref": [ { "equiv_sku": "52409", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52409" ], "locale_variants": {} }, { "sku": "52210", "brand": "SKF", "manufacturer_designation": "52210", "series": "52200-series", "type": "thrust_ball", "d_mm": 40, "D_mm": 78, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 49.4, "static_load_kN": 116, "fatigue_load_limit_kN": 4.3, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 710, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "52210 is SKF's 40 mm-bore double-direction thrust ball bearing in the 52200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 40×78×39 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 40 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 40×78×39 mm (1.575×3.071×1.535 in), 19.0 mm radial section, C 49.4 kN, C0 116 kN, Pu 4.3 kN. reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical), catalogue mass 710 g. Light-load floor: Pu = 4.3 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52210; the number is 9 % of the 49.4 kN dynamic rating. Mass and section check: 710 g inside the 40×78×39 mm outline leaves a 19.0 mm radial section, and the 116 kN static rating is 2.35× the dynamic rating — plan static safety and minimum preload against those figures. At the printed limiting speed of 3,400 r/min the mean pitch diameter dm ≈ 59.0 mm implies a dn value around 201k mm·r/min; the 2,400 r/min reference speed is the thermal-planning value under catalogue load. Rating split for documentation: dynamic 49.4 kN (L10 life), static 116 kN (safety factor s0), fatigue limit 4.3 kN (adjusted life) — three different uses of three different numbers for 52210, none interchangeable with another. Capacity density: 49.4 kN C from 0.710 kg of bearing steel gives about 69.6 kN per kilogram; static density is correspondingly 163.4 kN/kg at C0 116 kN. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 40 mm bore and 39 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 78 mm housing washers must remain free to slide during thermal movement.", "applications": [ "reversing gearbox shafts in one compact position", "elevator machinery thrust positions", "machine-tool lead screws and selector shafts" ], "failure_modes": [ "thermal lock-up when differential expansion removes the end play of the tighter-loaded side", "differential wear when one cage set loses lubrication first on a vertical mounting", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "washer face scoring from swarf trapped between the loose housing washer and its register", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Each direction independently needs the minimum axial load (factor A 0.069): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "The central shaft washer takes the interference fit on the 40 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "Do not replace a 52210 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 40×78 mm bore and OD.", "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 39 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "Ordering discipline for 52210: the catalogue page quotes 52210 and its 49.4/116 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52210?", "a": "52210 measures 40 mm bore × 78 mm OD × 39 mm bearing height (1.575 × 3.071 × 1.535 in), mass about 710 g. SKF 17000 ratings: C 49.4 kN, C0 116 kN, Pu 4.3 kN, reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical)." }, { "q": "What does the designation 52210 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 40 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "Which fits and retention does 52210 need?", "a": "The central shaft washer takes an interference fit on the 40 mm shaft; both housing washers run loose in their registers and must be positively retained, especially on vertical shafts, where the upper washer and its cage set also need lubricant retained." }, { "q": "What static check governs crane-hook duty for 52210?", "a": "Hook and screw positions are usually sized on C0 (116 kN here) with the application's static safety factor against peak stationary or shock thrust, not on the 49.4 kN L10 figure — reversal frequency then decides whether the 52-series geometry is acceptable." } ], "cross_ref": [ { "equiv_sku": "52210", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52210" ], "locale_variants": {} }, { "sku": "52310", "brand": "SKF", "manufacturer_designation": "52310", "series": "52300-series", "type": "thrust_ball", "d_mm": 40, "D_mm": 95, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 81.9, "static_load_kN": 170, "fatigue_load_limit_kN": 6.3, "reference_speed_rpm": 1800, "limiting_speed_rpm": 2600, "max_rpm": 2600, "weight_g": 1750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52310 is an ISO 104 double-direction thrust ball bearing, 40 mm bore and 95 mm OD on a flat housing seat, standing 58 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52310 is 40 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 40×95×58 mm (1.575×3.74×2.283 in), 27.5 mm radial section, C 81.9 kN, C0 170 kN, Pu 6.3 kN. reference speed 1,800 r/min (thermal) and limiting speed 2,600 r/min (mechanical), catalogue mass 1750 g. Capacity density: 81.9 kN C from 1.750 kg of bearing steel gives about 46.8 kN per kilogram; static density is correspondingly 97.1 kN/kg at C0 170 kN. Speed-ratio note for this exact unit: the reference speed is 1,800 r/min against a 2,600 r/min limiting speed, a reference-to-limit ratio of 0.69. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.19 at the 2,600 r/min limiting speed raises the required axial preload to about 5.9 kN; the reference-speed value 2.8 kN is the thermal design point. Minimum-load arithmetic: with dm ≈ 67.5 mm and factor A 0.19, Fam ≈ A·(n·dm/1000)² at the 1,800 r/min reference speed is about 2.8 kN for 52310; below that preload the balls skid and smear the tracks. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 2,600 r/min while thermal balance under catalogue load sets the 1,800 r/min reference; at dm ≈ 67.5 mm the corresponding dn is approximately 176k mm·r/min. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52310 is done separately per direction: if duty applies 81.9 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "steering and reversing linkages", "elevator machinery thrust positions", "reversing gearbox shafts in one compact position" ], "failure_modes": [ "brinelling of one track pair from a static reversing shock concentrated on a single side", "ball skidding on the momentarily unloaded side during rapid thrust reversal below the minimum load", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 58 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "The double-direction 52310 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 40 mm shaft axially in both directions instead of a mirrored pair.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52300 unit has no alignment capacity.", "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 2,600 r/min even a small thermal thrust preload smears the hottest track.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52310 as the double flat pressed steel execution; other order numbers of the 52310 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52310?", "a": "The catalogue envelope is 40×95×58 mm, mass 1750 g; ratings C 81.9 kN / C0 170 kN / Pu 6.3 kN, reference speed 1,800 r/min (thermal) and limiting speed 2,600 r/min (mechanical)." }, { "q": "What does the designation 52310 mean?", "a": "note the bore of 52310 is 40 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "When should I choose 52-series flat instead of 54-series sphered?", "a": "Choose the flat 52-series when the housing register can be machined square to the shaft; choose the 54-series with two U seat washers when initial misalignment has to be accommodated on fabricated or less rigid structures." }, { "q": "Can it replace two single-direction 51-series bearings?", "a": "It replaces a mirrored pair functionally — one fit, one housing bore, factory-matched geometry — but its 58 mm height is not twice the single-bearing height and seat details differ, so the housing and cover must be re-drawn rather than swapped in place." } ], "cross_ref": [ { "equiv_sku": "52310", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52310" ], "locale_variants": {} }, { "sku": "52211", "brand": "SKF", "manufacturer_designation": "52211", "series": "52200-series", "type": "thrust_ball", "d_mm": 45, "D_mm": 90, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 58.5, "static_load_kN": 134, "fatigue_load_limit_kN": 4.9, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52211 is an ISO 104 double-direction thrust ball bearing, 45 mm bore and 90 mm OD on a flat housing seat, standing 45 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52211 is 45 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 45×90×45 mm (1.772×3.543×1.772 in), 22.5 mm radial section, C 58.5 kN, C0 134 kN, Pu 4.9 kN. reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical), catalogue mass 1100 g. Sizing arithmetic on the 45 mm bore: 58.5 kN C over the 22.5 mm radial section gives 2.6 kN per section millimetre, and the 45 mm stack height is 2.00× that section — proportions typical of a 52200 thrust section. Imperial cross-check for procurement drawings: 1.772 in bore, 3.543 in OD, 1.772 in height, and the 1100 g catalogue mass converts to 1.100 kg (38.8 oz). Light-load floor: Pu = 4.9 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52211; the number is 8 % of the 58.5 kN dynamic rating. Minimum-load arithmetic: with dm ≈ 67.5 mm and factor A 0.11, Fam ≈ A·(n·dm/1000)² at the 2,200 r/min reference speed is about 2.4 kN for 52211; below that preload the balls skid and smear the tracks. Speed-ratio note for this exact unit: the reference speed is 2,200 r/min against a 3,000 r/min limiting speed, a reference-to-limit ratio of 0.73. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52211 is done separately per direction: if duty applies 58.5 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "vertical pumps with intermittent up-thrust", "elevator machinery thrust positions", "reversing gearbox shafts in one compact position" ], "failure_modes": [ "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "cage-set loss during handling because the five components separate as soon as the unit leaves the recess", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "overheating from grease overfill churning inside a sealed housing recess with no escape volume" ], "pitfalls": [ "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52200 unit has no alignment capacity.", "Do not replace a 52211 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 45×90 mm bore and OD.", "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 45 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "The double-direction 52211 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 45 mm shaft axially in both directions instead of a mirrored pair.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52211 as the double flat pressed steel execution; other order numbers of the 52211 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52211?", "a": "The catalogue envelope is 45×90×45 mm, mass 1100 g; ratings C 58.5 kN / C0 134 kN / Pu 4.9 kN, reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical)." }, { "q": "What does the designation 52211 mean?", "a": "note the bore of 52211 is 45 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "What minimum axial load applies to a double-direction bearing?", "a": "The Fam ≈ A·(n·dm/1000)² rule (factor A 0.11) applies to EACH direction: the momentarily unloaded side during slow reversal is the one that skids, so preload or balanced loading must keep both ball sets seated." }, { "q": "How is the double-direction 52211 constructed?", "a": "One central shaft washer with tracks on both faces and a ground bore, two housing washers facing outwards and two independent ball-cage assemblies — all supplied as one 45×90×45 mm unit locating the shaft axially in both directions." } ], "cross_ref": [ { "equiv_sku": "52211", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52211" ], "locale_variants": {} }, { "sku": "52311", "brand": "SKF", "manufacturer_designation": "52311", "series": "52300-series", "type": "thrust_ball", "d_mm": 45, "D_mm": 105, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 101, "static_load_kN": 224, "fatigue_load_limit_kN": 8.3, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 2400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 52300 series order number 52311 is a SKF double-direction thrust ball bearing for a 45 mm seat, built to ISO 104, with a flat housing seating surface, 45×105×64 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 45 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 45×105×64 mm (1.772×4.134×2.52 in), 30.0 mm radial section, C 101 kN, C0 224 kN, Pu 8.3 kN. reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical), catalogue mass 2400 g. Mass and section check: 2400 g inside the 45×105×64 mm outline leaves a 30.0 mm radial section, and the 224 kN static rating is 2.22× the dynamic rating — plan static safety and minimum preload against those figures. Light-load floor: Pu = 8.3 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52311; the number is 8 % of the 101 kN dynamic rating. Track-circle loading: per millimetre of mean track circumference the 101 kN dynamic rating corresponds to roughly 0.43 kN/mm of π·dm track, a useful comparison against the other dimension series of the 45 mm bore. Load balance: C0 224 kN against C 101 kN gives a 2.22 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 8.3 kN enters the adjusted-life check. Speed-ratio note for this exact unit: the reference speed is 1,600 r/min against a 2,200 r/min limiting speed, a reference-to-limit ratio of 0.73. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 45 mm bore and 64 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 105 mm housing washers must remain free to slide during thermal movement.", "applications": [ "elevator machinery thrust positions", "vertical pumps with intermittent up-thrust", "steering and reversing linkages" ], "failure_modes": [ "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "cover-induced thrust preload when the end cover is torqued solid instead of leaving the catalogue axial freedom", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 2,200 r/min even a small thermal thrust preload smears the hottest track.", "Service both cage sets together: replacing only the noisy side while leaving the worn 224 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Do not replace a 52311 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 45×105 mm bore and OD.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52300 unit has no alignment capacity.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52311 as the double flat pressed steel execution; other order numbers of the 52311 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52311?", "a": "Boundary dimensions to ISO 104: bore 45 mm, OD 105 mm, height 64 mm; weight 2400 g. Load figures from SKF 17000: dynamic 101 kN, static 224 kN, fatigue limit 8.3 kN; reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical)." }, { "q": "What does the designation 52311 mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 45 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "How is a vertical double-direction 52311 lubricated and retained?", "a": "Use an oil bath reaching the lower track plus a feed or oil level that serves the upper cage set, or a coherent heavy-base grease; positively retain both loose housing washers because gravity loads the upper stack differently at standstill." }, { "q": "Which fits and retention does 52311 need?", "a": "The central shaft washer takes an interference fit on the 45 mm shaft; both housing washers run loose in their registers and must be positively retained, especially on vertical shafts, where the upper washer and its cage set also need lubricant retained." } ], "cross_ref": [ { "equiv_sku": "52311", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52311" ], "locale_variants": {} }, { "sku": "52411", "brand": "SKF", "manufacturer_designation": "52411", "series": "52400-series", "type": "thrust_ball", "d_mm": 45, "D_mm": 120, "B_mm": 87, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 195, "static_load_kN": 400, "fatigue_load_limit_kN": 14.6, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 4700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52411 is an ISO 104 double-direction thrust ball bearing, 45 mm bore and 120 mm OD on a flat housing seat, standing 87 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52411 is 45 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 45×120×87 mm (1.772×4.724×3.425 in), 37.5 mm radial section, C 195 kN, C0 400 kN, Pu 14.6 kN. reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical), catalogue mass 4700 g. Speed-ratio note for this exact unit: the reference speed is 1,300 r/min against a 1,800 r/min limiting speed, a reference-to-limit ratio of 0.72. Bore-to-OD planning: OD 120 over bore 45 is a 2.67× step for this size, and the 87 mm height gives a bore/height ratio of 0.52; use these ratios when the housing recess around the 45 mm shaft is the first constraint. Stack/annulus proportions: the 87 mm axial stack over the 9,719 mm² washer annulus gives 8.95 mm of height per annular square millimetre ×10⁻³, and at 4700 g the bearing holds about 85.1 kN of C0 per kilogram. Section proportions: the 37.5 mm radial section compares with 45 mm of bore (section/bore ≈ 0.83) and the 87 mm height is 2.32× that section — the proportions that identify the 52400 envelope at a glance. Speed band width for this size is 500 r/min between reference and limiting (1.38× ratio); lubrication, preload and heat removal decide where inside that band 52411 can actually run. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 45 mm bore and 87 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 120 mm housing washers must remain free to slide during thermal movement.", "applications": [ "machine-tool lead screws and selector shafts", "vertical pumps with intermittent up-thrust", "elevator machinery thrust positions" ], "failure_modes": [ "ball skidding on the momentarily unloaded side during rapid thrust reversal below the minimum load", "track-edge spalling after the shaft washer seat is machined out of square and both rows share the tilt", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "The central shaft washer takes the interference fit on the 45 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52400 unit has no alignment capacity.", "Each direction independently needs the minimum axial load (factor A 0.79): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "Service both cage sets together: replacing only the noisy side while leaving the worn 400 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "The 195/400 kN figures belong to 52411 specifically (the double flat pressed steel execution of 52411); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52411?", "a": "The catalogue envelope is 45×120×87 mm, mass 4700 g; ratings C 195 kN / C0 400 kN / Pu 14.6 kN, reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical)." }, { "q": "What does the designation 52411 mean?", "a": "note the bore of 52411 is 45 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "When should I choose 52-series flat instead of 54-series sphered?", "a": "Choose the flat 52-series when the housing register can be machined square to the shaft; choose the 54-series with two U seat washers when initial misalignment has to be accommodated on fabricated or less rigid structures." }, { "q": "Can it replace two single-direction 51-series bearings?", "a": "It replaces a mirrored pair functionally — one fit, one housing bore, factory-matched geometry — but its 87 mm height is not twice the single-bearing height and seat details differ, so the housing and cover must be re-drawn rather than swapped in place." } ], "cross_ref": [ { "equiv_sku": "52411", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52411" ], "locale_variants": {} }, { "sku": "52212", "brand": "SKF", "manufacturer_designation": "52212", "series": "52200-series", "type": "thrust_ball", "d_mm": 50, "D_mm": 95, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 59.2, "static_load_kN": 140, "fatigue_load_limit_kN": 5.1, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 52200 series order number 52212 is a SKF double-direction thrust ball bearing for a 50 mm seat, built to ISO 104, with a flat housing seating surface, 50×95×46 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 50 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 50×95×46 mm (1.969×3.74×1.811 in), 22.5 mm radial section, C 59.2 kN, C0 140 kN, Pu 5.1 kN. reference speed 2,000 r/min (thermal) and limiting speed 2,800 r/min (mechanical), catalogue mass 1200 g. Minimum-load arithmetic: with dm ≈ 72.5 mm and factor A 0.12, Fam ≈ A·(n·dm/1000)² at the 2,000 r/min reference speed is about 2.5 kN for 52212; below that preload the balls skid and smear the tracks. Load balance: C0 140 kN against C 59.2 kN gives a 2.36 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 5.1 kN enters the adjusted-life check. Bore-to-OD planning: OD 95 over bore 50 is a 1.90× step for this size, and the 46 mm height gives a bore/height ratio of 1.09; use these ratios when the housing recess around the 50 mm shaft is the first constraint. Light-load floor: Pu = 5.1 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52212; the number is 9 % of the 59.2 kN dynamic rating. Static-first selection data: 140 kN C0 spread across the 46 mm stack gives 3.0 kN of static rating per height millimetre, and the 1200 g mass/C0 ratio is about 9 g per static kN — crane-hook and screw positions are normally sized on these two figures. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 50 mm bore and 46 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 95 mm housing washers must remain free to slide during thermal movement.", "applications": [ "steering and reversing linkages", "elevator machinery thrust positions", "reversing gearbox shafts in one compact position" ], "failure_modes": [ "thermal lock-up when differential expansion removes the end play of the tighter-loaded side", "assembly damage when the central shaft washer is fitted reversed or the two outward-facing housing washers are swapped", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "washer face scoring from swarf trapped between the loose housing washer and its register", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 2,800 r/min even a small thermal thrust preload smears the hottest track.", "Service both cage sets together: replacing only the noisy side while leaving the worn 140 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Do not replace a 52212 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 50×95 mm bore and OD.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52200 unit has no alignment capacity.", "Ordering discipline for 52212: the catalogue page quotes 52212 and its 59.2/140 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52212?", "a": "Boundary dimensions to ISO 104: bore 50 mm, OD 95 mm, height 46 mm; weight 1200 g. Load figures from SKF 17000: dynamic 59.2 kN, static 140 kN, fatigue limit 5.1 kN; reference speed 2,000 r/min (thermal) and limiting speed 2,800 r/min (mechanical)." }, { "q": "What does the designation 52212 mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 50 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "What minimum axial load applies to a double-direction bearing?", "a": "The Fam ≈ A·(n·dm/1000)² rule (factor A 0.12) applies to EACH direction: the momentarily unloaded side during slow reversal is the one that skids, so preload or balanced loading must keep both ball sets seated." }, { "q": "How is the double-direction 52212 constructed?", "a": "One central shaft washer with tracks on both faces and a ground bore, two housing washers facing outwards and two independent ball-cage assemblies — all supplied as one 50×95×46 mm unit locating the shaft axially in both directions." } ], "cross_ref": [ { "equiv_sku": "52212", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52212" ], "locale_variants": {} }, { "sku": "52312", "brand": "SKF", "manufacturer_designation": "52312", "series": "52300-series", "type": "thrust_ball", "d_mm": 50, "D_mm": 110, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 101, "static_load_kN": 224, "fatigue_load_limit_kN": 8.3, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 2550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "52312 is SKF's 50 mm-bore double-direction thrust ball bearing in the 52300 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 50×110×64 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 50 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 50×110×64 mm (1.969×4.331×2.52 in), 30.0 mm radial section, C 101 kN, C0 224 kN, Pu 8.3 kN. reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical), catalogue mass 2550 g. Mass and section check: 2550 g inside the 50×110×64 mm outline leaves a 30.0 mm radial section, and the 224 kN static rating is 2.22× the dynamic rating — plan static safety and minimum preload against those figures. Envelope economics: the 64 mm axial height over a 30.0 mm radial section yields 1.6 kN of dynamic capacity per height millimetre, and the bearing weighs 2550 g for 101 kN C — about 25 g per rated kN. Load balance: C0 224 kN against C 101 kN gives a 2.22 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 8.3 kN enters the adjusted-life check. Light-load floor: Pu = 8.3 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52312; the number is 8 % of the 101 kN dynamic rating. Bore-to-OD planning: OD 110 over bore 50 is a 2.20× step for this size, and the 64 mm height gives a bore/height ratio of 0.78; use these ratios when the housing recess around the 50 mm shaft is the first constraint. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52312 is done separately per direction: if duty applies 101 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "machine-tool lead screws and selector shafts", "reversing gearbox shafts in one compact position", "vertical pumps with intermittent up-thrust" ], "failure_modes": [ "track-edge spalling after the shaft washer seat is machined out of square and both rows share the tilt", "cage-set loss during handling because the five components separate as soon as the unit leaves the recess", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 2,200 r/min even a small thermal thrust preload smears the hottest track.", "Service both cage sets together: replacing only the noisy side while leaving the worn 224 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Do not replace a 52312 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 50×110 mm bore and OD.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52300 unit has no alignment capacity.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52312 as the double flat pressed steel execution; other order numbers of the 52312 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52312?", "a": "52312 measures 50 mm bore × 110 mm OD × 64 mm bearing height (1.969 × 4.331 × 2.52 in), mass about 2550 g. SKF 17000 ratings: C 101 kN, C0 224 kN, Pu 8.3 kN, reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical)." }, { "q": "What does the designation 52312 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 50 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "When should I choose 52-series flat instead of 54-series sphered?", "a": "Choose the flat 52-series when the housing register can be machined square to the shaft; choose the 54-series with two U seat washers when initial misalignment has to be accommodated on fabricated or less rigid structures." }, { "q": "Can it replace two single-direction 51-series bearings?", "a": "It replaces a mirrored pair functionally — one fit, one housing bore, factory-matched geometry — but its 64 mm height is not twice the single-bearing height and seat details differ, so the housing and cover must be re-drawn rather than swapped in place." } ], "cross_ref": [ { "equiv_sku": "52312", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52312" ], "locale_variants": {} }, { "sku": "52412-M", "brand": "SKF", "manufacturer_designation": "52412 M", "series": "52400-series", "type": "thrust_ball", "d_mm": 50, "D_mm": 130, "B_mm": 93, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 199, "static_load_kN": 430, "fatigue_load_limit_kN": 16, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1700, "max_rpm": 1700, "weight_g": 6350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 52400 series order number 52412 M is a SKF double-direction thrust ball bearing for a 50 mm seat, built to ISO 104, with a flat housing seating surface, 50×130×93 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 50 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 50×130×93 mm (1.969×5.118×3.661 in), 40.0 mm radial section, C 199 kN, C0 430 kN, Pu 16 kN. reference speed 1,200 r/min (thermal) and limiting speed 1,700 r/min (mechanical), catalogue mass 6350 g. Section proportions: the 40.0 mm radial section compares with 50 mm of bore (section/bore ≈ 0.80) and the 93 mm height is 2.33× that section — the proportions that identify the 52400 envelope at a glance. Envelope economics: the 93 mm axial height over a 40.0 mm radial section yields 2.1 kN of dynamic capacity per height millimetre, and the bearing weighs 6350 g for 199 kN C — about 32 g per rated kN. Speed-ratio note for this exact unit: the reference speed is 1,200 r/min against a 1,700 r/min limiting speed, a reference-to-limit ratio of 0.71. Rating split for documentation: dynamic 199 kN (L10 life), static 430 kN (safety factor s0), fatigue limit 16 kN (adjusted life) — three different uses of three different numbers for 52412 M, none interchangeable with another. Track-circle loading: per millimetre of mean track circumference the 199 kN dynamic rating corresponds to roughly 0.70 kN/mm of π·dm track, a useful comparison against the other dimension series of the 50 mm bore. Heavy double-direction note: the M suffix on a 52/54-series bearing means both ball-cage assemblies are machined brass and ball-centred for the largest bidirectional positions; both cage sets share the same lubrication requirement, so the oil or grease feed must reach the upper as well as the lower track on vertical shafts. The M suffix means BOTH cage sets of the 93 mm stack are machined brass; spare-part orders of one side should still be placed as the complete 52412 M unit, because mixed cage executions in one double-direction stack are not a catalogue configuration.", "applications": [ "steering and reversing linkages", "elevator machinery thrust positions", "reversing gearbox shafts in one compact position" ], "failure_modes": [ "cage-set loss during handling because the five components separate as soon as the unit leaves the recess", "assembly damage when the central shaft washer is fitted reversed or the two outward-facing housing washers are swapped", "upper brass-cage starvation on a vertical shaft whose lubricant feeds only the lower track pair", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The central shaft washer takes the interference fit on the 50 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52400 unit has no alignment capacity.", "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 93 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "Service both cage sets together: replacing only the noisy side while leaving the worn 430 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "The 199/430 kN figures belong to 52412 M specifically (the double flat brass execution of 52412); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52412-M?", "a": "Boundary dimensions to ISO 104: bore 50 mm, OD 130 mm, height 93 mm; weight 6350 g. Load figures from SKF 17000: dynamic 199 kN, static 430 kN, fatigue limit 16 kN; reference speed 1,200 r/min (thermal) and limiting speed 1,700 r/min (mechanical)." }, { "q": "What does the designation 52412 M mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 50 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "When should I choose 52-series flat instead of 54-series sphered?", "a": "Choose the flat 52-series when the housing register can be machined square to the shaft; choose the 54-series with two U seat washers when initial misalignment has to be accommodated on fabricated or less rigid structures." }, { "q": "Can it replace two single-direction 51-series bearings?", "a": "It replaces a mirrored pair functionally — one fit, one housing bore, factory-matched geometry — but its 93 mm height is not twice the single-bearing height and seat details differ, so the housing and cover must be re-drawn rather than swapped in place." } ], "cross_ref": [ { "equiv_sku": "52412", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52412-M", "52412 M" ], "locale_variants": {} }, { "sku": "52213", "brand": "SKF", "manufacturer_designation": "52213", "series": "52200-series", "type": "thrust_ball", "d_mm": 55, "D_mm": 100, "B_mm": 47, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 60.5, "static_load_kN": 150, "fatigue_load_limit_kN": 5.5, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 1350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 52200 series order number 52213 is a SKF double-direction thrust ball bearing for a 55 mm seat, built to ISO 104, with a flat housing seating surface, 55×100×47 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 55 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 55×100×47 mm (2.165×3.937×1.85 in), 22.5 mm radial section, C 60.5 kN, C0 150 kN, Pu 5.5 kN. reference speed 2,000 r/min (thermal) and limiting speed 2,800 r/min (mechanical), catalogue mass 1350 g. Speed band width for this size is 800 r/min between reference and limiting (1.40× ratio); lubrication, preload and heat removal decide where inside that band 52213 can actually run. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 2,800 r/min while thermal balance under catalogue load sets the 2,000 r/min reference; at dm ≈ 77.5 mm the corresponding dn is approximately 217k mm·r/min. Sizing arithmetic on the 55 mm bore: 60.5 kN C over the 22.5 mm radial section gives 2.7 kN per section millimetre, and the 47 mm stack height is 2.09× that section — proportions typical of a 52200 thrust section. Capacity density: 60.5 kN C from 1.350 kg of bearing steel gives about 44.8 kN per kilogram; static density is correspondingly 111.1 kN/kg at C0 150 kN. Section proportions: the 22.5 mm radial section compares with 55 mm of bore (section/bore ≈ 0.41) and the 47 mm height is 2.09× that section — the proportions that identify the 52200 envelope at a glance. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52213 is done separately per direction: if duty applies 60.5 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "steering and reversing linkages", "machine-tool lead screws and selector shafts", "elevator machinery thrust positions" ], "failure_modes": [ "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "cover-induced thrust preload when the end cover is torqued solid instead of leaving the catalogue axial freedom", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 47 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "The double-direction 52213 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 55 mm shaft axially in both directions instead of a mirrored pair.", "Each direction independently needs the minimum axial load (factor A 0.14): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 2,800 r/min even a small thermal thrust preload smears the hottest track.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52213 as the double flat pressed steel execution; other order numbers of the 52213 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52213?", "a": "Boundary dimensions to ISO 104: bore 55 mm, OD 100 mm, height 47 mm; weight 1350 g. Load figures from SKF 17000: dynamic 60.5 kN, static 150 kN, fatigue limit 5.5 kN; reference speed 2,000 r/min (thermal) and limiting speed 2,800 r/min (mechanical)." }, { "q": "What does the designation 52213 mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 55 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "Can it replace two single-direction 51-series bearings?", "a": "It replaces a mirrored pair functionally — one fit, one housing bore, factory-matched geometry — but its 47 mm height is not twice the single-bearing height and seat details differ, so the housing and cover must be re-drawn rather than swapped in place." }, { "q": "How is a vertical double-direction 52213 lubricated and retained?", "a": "Use an oil bath reaching the lower track plus a feed or oil level that serves the upper cage set, or a coherent heavy-base grease; positively retain both loose housing washers because gravity loads the upper stack differently at standstill." } ], "cross_ref": [ { "equiv_sku": "52213", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52213" ], "locale_variants": {} }, { "sku": "52214", "brand": "SKF", "manufacturer_designation": "52214", "series": "52200-series", "type": "thrust_ball", "d_mm": 55, "D_mm": 105, "B_mm": 47, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 62.4, "static_load_kN": 160, "fatigue_load_limit_kN": 5.85, "reference_speed_rpm": 1900, "limiting_speed_rpm": 2600, "max_rpm": 2600, "weight_g": 1500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "52214 is SKF's 55 mm-bore double-direction thrust ball bearing in the 52200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 55×105×47 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 55 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 55×105×47 mm (2.165×4.134×1.85 in), 25.0 mm radial section, C 62.4 kN, C0 160 kN, Pu 5.85 kN. reference speed 1,900 r/min (thermal) and limiting speed 2,600 r/min (mechanical), catalogue mass 1500 g. Light-load floor: Pu = 5.85 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52214; the number is 9 % of the 62.4 kN dynamic rating. Stack/annulus proportions: the 47 mm axial stack over the 6,283 mm² washer annulus gives 7.48 mm of height per annular square millimetre ×10⁻³, and at 1500 g the bearing holds about 106.7 kN of C0 per kilogram. Section proportions: the 25.0 mm radial section compares with 55 mm of bore (section/bore ≈ 0.45) and the 47 mm height is 1.88× that section — the proportions that identify the 52200 envelope at a glance. Speed band width for this size is 700 r/min between reference and limiting (1.37× ratio); lubrication, preload and heat removal decide where inside that band 52214 can actually run. Envelope economics: the 47 mm axial height over a 25.0 mm radial section yields 1.3 kN of dynamic capacity per height millimetre, and the bearing weighs 1500 g for 62.4 kN C — about 24 g per rated kN. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 55 mm bore and 47 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 105 mm housing washers must remain free to slide during thermal movement.", "applications": [ "reversing gearbox shafts in one compact position", "elevator machinery thrust positions", "vertical pumps with intermittent up-thrust" ], "failure_modes": [ "ball skidding on the momentarily unloaded side during rapid thrust reversal below the minimum load", "cage-set loss during handling because the five components separate as soon as the unit leaves the recess", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "washer face scoring from swarf trapped between the loose housing washer and its register", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "Each direction independently needs the minimum axial load (factor A 0.16): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "The central shaft washer takes the interference fit on the 55 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "Service both cage sets together: replacing only the noisy side while leaving the worn 160 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Do not replace a 52214 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 55×105 mm bore and OD.", "The 62.4/160 kN figures belong to 52214 specifically (the double flat pressed steel execution of 52214); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52214?", "a": "52214 measures 55 mm bore × 105 mm OD × 47 mm bearing height (2.165 × 4.134 × 1.85 in), mass about 1500 g. SKF 17000 ratings: C 62.4 kN, C0 160 kN, Pu 5.85 kN, reference speed 1,900 r/min (thermal) and limiting speed 2,600 r/min (mechanical)." }, { "q": "What does the designation 52214 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 55 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "What minimum axial load applies to a double-direction bearing?", "a": "The Fam ≈ A·(n·dm/1000)² rule (factor A 0.16) applies to EACH direction: the momentarily unloaded side during slow reversal is the one that skids, so preload or balanced loading must keep both ball sets seated." }, { "q": "How is the double-direction 52214 constructed?", "a": "One central shaft washer with tracks on both faces and a ground bore, two housing washers facing outwards and two independent ball-cage assemblies — all supplied as one 55×105×47 mm unit locating the shaft axially in both directions." } ], "cross_ref": [ { "equiv_sku": "52214", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52214" ], "locale_variants": {} }, { "sku": "52313", "brand": "SKF", "manufacturer_designation": "52313", "series": "52300-series", "type": "thrust_ball", "d_mm": 55, "D_mm": 115, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 106, "static_load_kN": 240, "fatigue_load_limit_kN": 8.8, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 2750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "52313 is SKF's 55 mm-bore double-direction thrust ball bearing in the 52300 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 55×115×64 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 55 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 55×115×64 mm (2.165×4.528×2.52 in), 30.0 mm radial section, C 106 kN, C0 240 kN, Pu 8.8 kN. reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical), catalogue mass 2750 g. Selection figures for 52313: the C0/C ratio is 2.26, Pu 8.8 kN is about 8 % of C, and the catalogue mass works out to roughly 50 g per millimetre of bore; the printed minimum-load factor is A 0.3. Pitch-diameter arithmetic: dm = (55+115)/2 = 85.0 mm; at the 2,200 r/min limiting speed that corresponds to roughly 187k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Mass and section check: 2750 g inside the 55×115×64 mm outline leaves a 30.0 mm radial section, and the 240 kN static rating is 2.26× the dynamic rating — plan static safety and minimum preload against those figures. Minimum-load arithmetic: with dm ≈ 85.0 mm and factor A 0.3, Fam ≈ A·(n·dm/1000)² at the 1,600 r/min reference speed is about 5.5 kN for 52313; below that preload the balls skid and smear the tracks. Section proportions: the 30.0 mm radial section compares with 55 mm of bore (section/bore ≈ 0.55) and the 64 mm height is 2.13× that section — the proportions that identify the 52300 envelope at a glance. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52313 is done separately per direction: if duty applies 106 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "machine-tool lead screws and selector shafts", "steering and reversing linkages", "vertical pumps with intermittent up-thrust" ], "failure_modes": [ "brinelling of one track pair from a static reversing shock concentrated on a single side", "differential wear when one cage set loses lubrication first on a vertical mounting", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Service both cage sets together: replacing only the noisy side while leaving the worn 240 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 64 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "The double-direction 52313 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 55 mm shaft axially in both directions instead of a mirrored pair.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52300 unit has no alignment capacity.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52313 as the double flat pressed steel execution; other order numbers of the 52313 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52313?", "a": "52313 measures 55 mm bore × 115 mm OD × 64 mm bearing height (2.165 × 4.528 × 2.52 in), mass about 2750 g. SKF 17000 ratings: C 106 kN, C0 240 kN, Pu 8.8 kN, reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical)." }, { "q": "What does the designation 52313 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 55 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "Which fits and retention does 52313 need?", "a": "The central shaft washer takes an interference fit on the 55 mm shaft; both housing washers run loose in their registers and must be positively retained, especially on vertical shafts, where the upper washer and its cage set also need lubricant retained." }, { "q": "What static check governs crane-hook duty for 52313?", "a": "Hook and screw positions are usually sized on C0 (240 kN here) with the application's static safety factor against peak stationary or shock thrust, not on the 106 kN L10 figure — reversal frequency then decides whether the 52-series geometry is acceptable." } ], "cross_ref": [ { "equiv_sku": "52313", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52313" ], "locale_variants": {} }, { "sku": "52314", "brand": "SKF", "manufacturer_designation": "52314", "series": "52300-series", "type": "thrust_ball", "d_mm": 55, "D_mm": 125, "B_mm": 72, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 135, "static_load_kN": 320, "fatigue_load_limit_kN": 11.8, "reference_speed_rpm": 1400, "limiting_speed_rpm": 2000, "max_rpm": 2000, "weight_g": 3650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52314 is an ISO 104 double-direction thrust ball bearing, 55 mm bore and 125 mm OD on a flat housing seat, standing 72 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52314 is 55 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 55×125×72 mm (2.165×4.921×2.835 in), 35.0 mm radial section, C 135 kN, C0 320 kN, Pu 11.8 kN. reference speed 1,400 r/min (thermal) and limiting speed 2,000 r/min (mechanical), catalogue mass 3650 g. Static-first selection data: 320 kN C0 spread across the 72 mm stack gives 4.4 kN of static rating per height millimetre, and the 3650 g mass/C0 ratio is about 11 g per static kN — crane-hook and screw positions are normally sized on these two figures. Envelope economics: the 72 mm axial height over a 35.0 mm radial section yields 1.9 kN of dynamic capacity per height millimetre, and the bearing weighs 3650 g for 135 kN C — about 27 g per rated kN. Washer-annulus check: the π/4·(D²−d²) contact annulus of 52314 covers about 9,896 mm², distributing C0 320 kN over a mean track circle of π·dm ≈ 283 mm. Minimum-load arithmetic: with dm ≈ 90.0 mm and factor A 0.53, Fam ≈ A·(n·dm/1000)² at the 1,400 r/min reference speed is about 8.4 kN for 52314; below that preload the balls skid and smear the tracks. Imperial cross-check for procurement drawings: 2.165 in bore, 4.921 in OD, 2.835 in height, and the 3650 g catalogue mass converts to 3.650 kg (128.7 oz). Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 55 mm bore and 72 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 125 mm housing washers must remain free to slide during thermal movement.", "applications": [ "steering and reversing linkages", "machine-tool lead screws and selector shafts", "reversing gearbox shafts in one compact position" ], "failure_modes": [ "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "brinelling of one track pair from a static reversing shock concentrated on a single side", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Service both cage sets together: replacing only the noisy side while leaving the worn 320 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 72 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52300 unit has no alignment capacity.", "Do not replace a 52314 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 55×125 mm bore and OD.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52314 as the double flat pressed steel execution; other order numbers of the 52314 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52314?", "a": "The catalogue envelope is 55×125×72 mm, mass 3650 g; ratings C 135 kN / C0 320 kN / Pu 11.8 kN, reference speed 1,400 r/min (thermal) and limiting speed 2,000 r/min (mechanical)." }, { "q": "What does the designation 52314 mean?", "a": "note the bore of 52314 is 55 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "What minimum axial load applies to a double-direction bearing?", "a": "The Fam ≈ A·(n·dm/1000)² rule (factor A 0.53) applies to EACH direction: the momentarily unloaded side during slow reversal is the one that skids, so preload or balanced loading must keep both ball sets seated." }, { "q": "How is the double-direction 52314 constructed?", "a": "One central shaft washer with tracks on both faces and a ground bore, two housing washers facing outwards and two independent ball-cage assemblies — all supplied as one 55×125×72 mm unit locating the shaft axially in both directions." } ], "cross_ref": [ { "equiv_sku": "52314", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52314" ], "locale_variants": {} }, { "sku": "52414-M", "brand": "SKF", "manufacturer_designation": "52414 M", "series": "52400-series", "type": "thrust_ball", "d_mm": 55, "D_mm": 250, "B_mm": 107, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 234, "static_load_kN": 550, "fatigue_load_limit_kN": 19.3, "reference_speed_rpm": 800, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 9700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52414 M is an ISO 104 double-direction thrust ball bearing, 55 mm bore and 250 mm OD on a flat housing seat, standing 107 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52414 M is 55 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. Envelope 55×250×107 mm (2.165×9.843×4.213 in), 97.5 mm radial section, C 234 kN, C0 550 kN, Pu 19.3 kN. reference speed 800 r/min (thermal) and limiting speed 1,100 r/min (mechanical), catalogue mass 9700 g. Capacity density: 234 kN C from 9.700 kg of bearing steel gives about 24.1 kN per kilogram; static density is correspondingly 56.7 kN/kg at C0 550 kN. Bore-to-OD planning: OD 250 over bore 55 is a 4.55× step for this size, and the 107 mm height gives a bore/height ratio of 0.51; use these ratios when the housing recess around the 55 mm shaft is the first constraint. Pitch-diameter arithmetic: dm = (55+250)/2 = 152.5 mm; at the 1,100 r/min limiting speed that corresponds to roughly 168k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Light-load floor: Pu = 19.3 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52414 M; the number is 8 % of the 234 kN dynamic rating. Section proportions: the 97.5 mm radial section compares with 55 mm of bore (section/bore ≈ 1.77) and the 107 mm height is 1.10× that section — the proportions that identify the 52400 envelope at a glance. Heavy double-direction note: the M suffix on a 52/54-series bearing means both ball-cage assemblies are machined brass and ball-centred for the largest bidirectional positions; both cage sets share the same lubrication requirement, so the oil or grease feed must reach the upper as well as the lower track on vertical shafts. With 9700 g rotating partially with the shaft, check the rotor-balance influence of the central shaft washer at speeds approaching 1,100 r/min; the two loose washers do not rotate and contribute no imbalance.", "applications": [ "reversing gearbox shafts in one compact position", "steering and reversing linkages", "machine-tool lead screws and selector shafts" ], "failure_modes": [ "cage-set loss during handling because the five components separate as soon as the unit leaves the recess", "brinelling of one track pair from a static reversing shock concentrated on a single side", "upper brass-cage starvation on a vertical shaft whose lubricant feeds only the lower track pair", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 1,100 r/min even a small thermal thrust preload smears the hottest track.", "Service both cage sets together: replacing only the noisy side while leaving the worn 550 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Do not replace a 52414 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 55×250 mm bore and OD.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52400 unit has no alignment capacity.", "The 234/550 kN figures belong to 52414 M specifically (the double flat brass execution of 52414); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52414-M?", "a": "The catalogue envelope is 55×250×107 mm, mass 9700 g; ratings C 234 kN / C0 550 kN / Pu 19.3 kN, reference speed 800 r/min (thermal) and limiting speed 1,100 r/min (mechanical)." }, { "q": "What does the designation 52414 M mean?", "a": "note the bore of 52414 M is 55 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "How is a vertical double-direction 52414 lubricated and retained?", "a": "Use an oil bath reaching the lower track plus a feed or oil level that serves the upper cage set, or a coherent heavy-base grease; positively retain both loose housing washers because gravity loads the upper stack differently at standstill." }, { "q": "Which fits and retention does 52414-M need?", "a": "The central shaft washer takes an interference fit on the 55 mm shaft; both housing washers run loose in their registers and must be positively retained, especially on vertical shafts, where the upper washer and its cage set also need lubricant retained." } ], "cross_ref": [ { "equiv_sku": "52414", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52414-M", "52414 M" ], "locale_variants": {} }, { "sku": "52215", "brand": "SKF", "manufacturer_designation": "52215", "series": "52200-series", "type": "thrust_ball", "d_mm": 60, "D_mm": 110, "B_mm": 47, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 63.7, "static_load_kN": 170, "fatigue_load_limit_kN": 6.2, "reference_speed_rpm": 1900, "limiting_speed_rpm": 2600, "max_rpm": 2600, "weight_g": 1550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "52215 is SKF's 60 mm-bore double-direction thrust ball bearing in the 52200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 60×110×47 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 60 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 60×110×47 mm (2.362×4.331×1.85 in), 25.0 mm radial section, C 63.7 kN, C0 170 kN, Pu 6.2 kN. reference speed 1,900 r/min (thermal) and limiting speed 2,600 r/min (mechanical), catalogue mass 1550 g. Pitch-diameter arithmetic: dm = (60+110)/2 = 85.0 mm; at the 2,600 r/min limiting speed that corresponds to roughly 221k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Track-circle loading: per millimetre of mean track circumference the 63.7 kN dynamic rating corresponds to roughly 0.24 kN/mm of π·dm track, a useful comparison against the other dimension series of the 60 mm bore. Speed band width for this size is 700 r/min between reference and limiting (1.37× ratio); lubrication, preload and heat removal decide where inside that band 52215 can actually run. Light-load floor: Pu = 6.2 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52215; the number is 10 % of the 63.7 kN dynamic rating. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 2,600 r/min while thermal balance under catalogue load sets the 1,900 r/min reference; at dm ≈ 85.0 mm the corresponding dn is approximately 221k mm·r/min. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52215 is done separately per direction: if duty applies 63.7 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "crane travel and slewing drives", "heavy reversing gearbox shafts", "large lead-screw and press adjustment" ], "failure_modes": [ "track-edge spalling after the shaft washer seat is machined out of square and both rows share the tilt", "differential wear when one cage set loses lubrication first on a vertical mounting", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 47 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "The double-direction 52215 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 60 mm shaft axially in both directions instead of a mirrored pair.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52200 unit has no alignment capacity.", "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 2,600 r/min even a small thermal thrust preload smears the hottest track.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52215 as the double flat pressed steel execution; other order numbers of the 52215 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52215?", "a": "52215 measures 60 mm bore × 110 mm OD × 47 mm bearing height (2.362 × 4.331 × 1.85 in), mass about 1550 g. SKF 17000 ratings: C 63.7 kN, C0 170 kN, Pu 6.2 kN, reference speed 1,900 r/min (thermal) and limiting speed 2,600 r/min (mechanical)." }, { "q": "What does the designation 52215 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 60 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "How is the double-direction 52215 constructed?", "a": "One central shaft washer with tracks on both faces and a ground bore, two housing washers facing outwards and two independent ball-cage assemblies — all supplied as one 60×110×47 mm unit locating the shaft axially in both directions." }, { "q": "When should I choose 52-series flat instead of 54-series sphered?", "a": "Choose the flat 52-series when the housing register can be machined square to the shaft; choose the 54-series with two U seat washers when initial misalignment has to be accommodated on fabricated or less rigid structures." } ], "cross_ref": [ { "equiv_sku": "52215", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52215" ], "locale_variants": {} }, { "sku": "52315", "brand": "SKF", "manufacturer_designation": "52315", "series": "52300-series", "type": "thrust_ball", "d_mm": 60, "D_mm": 135, "B_mm": 79, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 163, "static_load_kN": 390, "fatigue_load_limit_kN": 14, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 4800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 52300 series order number 52315 is a SKF double-direction thrust ball bearing for a 60 mm seat, built to ISO 104, with a flat housing seating surface, 60×135×79 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 60 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 60×135×79 mm (2.362×5.315×3.11 in), 37.5 mm radial section, C 163 kN, C0 390 kN, Pu 14 kN. reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical), catalogue mass 4800 g. Minimum-load arithmetic: with dm ≈ 97.5 mm and factor A 0.79, Fam ≈ A·(n·dm/1000)² at the 1,300 r/min reference speed is about 12.7 kN for 52315; below that preload the balls skid and smear the tracks. Rating split for documentation: dynamic 163 kN (L10 life), static 390 kN (safety factor s0), fatigue limit 14 kN (adjusted life) — three different uses of three different numbers for 52315, none interchangeable with another. Track-circle loading: per millimetre of mean track circumference the 163 kN dynamic rating corresponds to roughly 0.53 kN/mm of π·dm track, a useful comparison against the other dimension series of the 60 mm bore. Section proportions: the 37.5 mm radial section compares with 60 mm of bore (section/bore ≈ 0.63) and the 79 mm height is 2.11× that section — the proportions that identify the 52300 envelope at a glance. Speed band width for this size is 500 r/min between reference and limiting (1.38× ratio); lubrication, preload and heat removal decide where inside that band 52315 can actually run. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 60 mm bore and 79 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 135 mm housing washers must remain free to slide during thermal movement.", "applications": [ "large lead-screw and press adjustment", "winch and hoist reversal positions", "heavy reversing gearbox shafts" ], "failure_modes": [ "cage-set loss during handling because the five components separate as soon as the unit leaves the recess", "assembly damage when the central shaft washer is fitted reversed or the two outward-facing housing washers are swapped", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "washer face scoring from swarf trapped between the loose housing washer and its register", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Each direction independently needs the minimum axial load (factor A 0.79): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "The central shaft washer takes the interference fit on the 60 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "Do not replace a 52315 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 60×135 mm bore and OD.", "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 79 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "The 163/390 kN figures belong to 52315 specifically (the double flat pressed steel execution of 52315); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52315?", "a": "Boundary dimensions to ISO 104: bore 60 mm, OD 135 mm, height 79 mm; weight 4800 g. Load figures from SKF 17000: dynamic 163 kN, static 390 kN, fatigue limit 14 kN; reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical)." }, { "q": "What does the designation 52315 mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 60 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "Which fits and retention does 52315 need?", "a": "The central shaft washer takes an interference fit on the 60 mm shaft; both housing washers run loose in their registers and must be positively retained, especially on vertical shafts, where the upper washer and its cage set also need lubricant retained." }, { "q": "What static check governs crane-hook duty for 52315?", "a": "Hook and screw positions are usually sized on C0 (390 kN here) with the application's static safety factor against peak stationary or shock thrust, not on the 163 kN L10 figure — reversal frequency then decides whether the 52-series geometry is acceptable." } ], "cross_ref": [ { "equiv_sku": "52315", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52315" ], "locale_variants": {} }, { "sku": "52216", "brand": "SKF", "manufacturer_designation": "52216", "series": "52200-series", "type": "thrust_ball", "d_mm": 65, "D_mm": 115, "B_mm": 48, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 76.1, "static_load_kN": 208, "fatigue_load_limit_kN": 7.65, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 52200 series order number 52216 is a SKF double-direction thrust ball bearing for a 65 mm seat, built to ISO 104, with a flat housing seating surface, 65×115×48 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 65 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 65×115×48 mm (2.559×4.528×1.89 in), 25.0 mm radial section, C 76.1 kN, C0 208 kN, Pu 7.65 kN. reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical), catalogue mass 1700 g. Light-load floor: Pu = 7.65 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52216; the number is 10 % of the 76.1 kN dynamic rating. Load balance: C0 208 kN against C 76.1 kN gives a 2.73 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 7.65 kN enters the adjusted-life check. Section proportions: the 25.0 mm radial section compares with 65 mm of bore (section/bore ≈ 0.38) and the 48 mm height is 1.92× that section — the proportions that identify the 52200 envelope at a glance. Sizing arithmetic on the 65 mm bore: 76.1 kN C over the 25.0 mm radial section gives 3.0 kN per section millimetre, and the 48 mm stack height is 1.92× that section — proportions typical of a 52200 thrust section. Imperial cross-check for procurement drawings: 2.559 in bore, 4.528 in OD, 1.89 in height, and the 1700 g catalogue mass converts to 1.700 kg (60.0 oz). Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 65 mm bore and 48 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 115 mm housing washers must remain free to slide during thermal movement.", "applications": [ "heavy reversing gearbox shafts", "vertical motors subject to start-up up-thrust", "large lead-screw and press adjustment" ], "failure_modes": [ "cover-induced thrust preload when the end cover is torqued solid instead of leaving the catalogue axial freedom", "brinelling of one track pair from a static reversing shock concentrated on a single side", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "track rust staining from condensate during long idle periods in humid plant air", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Each direction independently needs the minimum axial load (factor A 0.22): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "The central shaft washer takes the interference fit on the 65 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "The double-direction 52216 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 65 mm shaft axially in both directions instead of a mirrored pair.", "Do not replace a 52216 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 65×115 mm bore and OD.", "Ordering discipline for 52216: the catalogue page quotes 52216 and its 76.1/208 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52216?", "a": "Boundary dimensions to ISO 104: bore 65 mm, OD 115 mm, height 48 mm; weight 1700 g. Load figures from SKF 17000: dynamic 76.1 kN, static 208 kN, fatigue limit 7.65 kN; reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical)." }, { "q": "What does the designation 52216 mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 65 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "What minimum axial load applies to a double-direction bearing?", "a": "The Fam ≈ A·(n·dm/1000)² rule (factor A 0.22) applies to EACH direction: the momentarily unloaded side during slow reversal is the one that skids, so preload or balanced loading must keep both ball sets seated." }, { "q": "How is the double-direction 52216 constructed?", "a": "One central shaft washer with tracks on both faces and a ground bore, two housing washers facing outwards and two independent ball-cage assemblies — all supplied as one 65×115×48 mm unit locating the shaft axially in both directions." } ], "cross_ref": [ { "equiv_sku": "52216", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52216" ], "locale_variants": {} }, { "sku": "52316", "brand": "SKF", "manufacturer_designation": "52316", "series": "52300-series", "type": "thrust_ball", "d_mm": 65, "D_mm": 140, "B_mm": 79, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 159, "static_load_kN": 390, "fatigue_load_limit_kN": 13.7, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 4950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52316 is an ISO 104 double-direction thrust ball bearing, 65 mm bore and 140 mm OD on a flat housing seat, standing 79 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52316 is 65 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 65×140×79 mm (2.559×5.512×3.11 in), 37.5 mm radial section, C 159 kN, C0 390 kN, Pu 13.7 kN. reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical), catalogue mass 4950 g. Washer-annulus check: the π/4·(D²−d²) contact annulus of 52316 covers about 12,075 mm², distributing C0 390 kN over a mean track circle of π·dm ≈ 322 mm. Section proportions: the 37.5 mm radial section compares with 65 mm of bore (section/bore ≈ 0.58) and the 79 mm height is 2.11× that section — the proportions that identify the 52300 envelope at a glance. Selection figures for 52316: the C0/C ratio is 2.45, Pu 13.7 kN is about 9 % of C, and the catalogue mass works out to roughly 76 g per millimetre of bore; the printed minimum-load factor is A 0.79. Mass and section check: 4950 g inside the 65×140×79 mm outline leaves a 37.5 mm radial section, and the 390 kN static rating is 2.45× the dynamic rating — plan static safety and minimum preload against those figures. Static-first selection data: 390 kN C0 spread across the 79 mm stack gives 4.9 kN of static rating per height millimetre, and the 4950 g mass/C0 ratio is about 13 g per static kN — crane-hook and screw positions are normally sized on these two figures. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 65 mm bore and 79 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 140 mm housing washers must remain free to slide during thermal movement.", "applications": [ "heavy reversing gearbox shafts", "winch and hoist reversal positions", "vertical motors subject to start-up up-thrust" ], "failure_modes": [ "ball skidding on the momentarily unloaded side during rapid thrust reversal below the minimum load", "brinelling of one track pair from a static reversing shock concentrated on a single side", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "The double-direction 52316 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 65 mm shaft axially in both directions instead of a mirrored pair.", "Each direction independently needs the minimum axial load (factor A 0.79): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "The central shaft washer takes the interference fit on the 65 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 1,800 r/min even a small thermal thrust preload smears the hottest track.", "The 159/390 kN figures belong to 52316 specifically (the double flat pressed steel execution of 52316); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52316?", "a": "The catalogue envelope is 65×140×79 mm, mass 4950 g; ratings C 159 kN / C0 390 kN / Pu 13.7 kN, reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical)." }, { "q": "What does the designation 52316 mean?", "a": "note the bore of 52316 is 65 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "What static check governs crane-hook duty for 52316?", "a": "Hook and screw positions are usually sized on C0 (390 kN here) with the application's static safety factor against peak stationary or shock thrust, not on the 159 kN L10 figure — reversal frequency then decides whether the 52-series geometry is acceptable." }, { "q": "What minimum axial load applies to a double-direction bearing?", "a": "The Fam ≈ A·(n·dm/1000)² rule (factor A 0.79) applies to EACH direction: the momentarily unloaded side during slow reversal is the one that skids, so preload or balanced loading must keep both ball sets seated." } ], "cross_ref": [ { "equiv_sku": "52316", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52316" ], "locale_variants": {} }, { "sku": "52217", "brand": "SKF", "manufacturer_designation": "52217", "series": "52200-series", "type": "thrust_ball", "d_mm": 70, "D_mm": 125, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 97.5, "static_load_kN": 275, "fatigue_load_limit_kN": 9.8, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 2400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 52200 series order number 52217 is a SKF double-direction thrust ball bearing for a 70 mm seat, built to ISO 104, with a flat housing seating surface, 70×125×55 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 70 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 70×125×55 mm (2.756×4.921×2.165 in), 27.5 mm radial section, C 97.5 kN, C0 275 kN, Pu 9.8 kN. reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical), catalogue mass 2400 g. Stack/annulus proportions: the 55 mm axial stack over the 8,423 mm² washer annulus gives 6.53 mm of height per annular square millimetre ×10⁻³, and at 2400 g the bearing holds about 114.6 kN of C0 per kilogram. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 2,200 r/min while thermal balance under catalogue load sets the 1,600 r/min reference; at dm ≈ 97.5 mm the corresponding dn is approximately 215k mm·r/min. Pitch-diameter arithmetic: dm = (70+125)/2 = 97.5 mm; at the 2,200 r/min limiting speed that corresponds to roughly 215k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Section proportions: the 27.5 mm radial section compares with 70 mm of bore (section/bore ≈ 0.39) and the 55 mm height is 2.00× that section — the proportions that identify the 52200 envelope at a glance. Speed band width for this size is 600 r/min between reference and limiting (1.38× ratio); lubrication, preload and heat removal decide where inside that band 52217 can actually run. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52217 is done separately per direction: if duty applies 97.5 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "vertical motors subject to start-up up-thrust", "large lead-screw and press adjustment", "winch and hoist reversal positions" ], "failure_modes": [ "differential wear when one cage set loses lubrication first on a vertical mounting", "assembly damage when the central shaft washer is fitted reversed or the two outward-facing housing washers are swapped", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 2,200 r/min even a small thermal thrust preload smears the hottest track.", "Service both cage sets together: replacing only the noisy side while leaving the worn 275 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Do not replace a 52217 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 70×125 mm bore and OD.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52200 unit has no alignment capacity.", "The 97.5/275 kN figures belong to 52217 specifically (the double flat pressed steel execution of 52217); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52217?", "a": "Boundary dimensions to ISO 104: bore 70 mm, OD 125 mm, height 55 mm; weight 2400 g. Load figures from SKF 17000: dynamic 97.5 kN, static 275 kN, fatigue limit 9.8 kN; reference speed 1,600 r/min (thermal) and limiting speed 2,200 r/min (mechanical)." }, { "q": "What does the designation 52217 mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 70 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "When should I choose 52-series flat instead of 54-series sphered?", "a": "Choose the flat 52-series when the housing register can be machined square to the shaft; choose the 54-series with two U seat washers when initial misalignment has to be accommodated on fabricated or less rigid structures." }, { "q": "Can it replace two single-direction 51-series bearings?", "a": "It replaces a mirrored pair functionally — one fit, one housing bore, factory-matched geometry — but its 55 mm height is not twice the single-bearing height and seat details differ, so the housing and cover must be re-drawn rather than swapped in place." } ], "cross_ref": [ { "equiv_sku": "52217", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52217" ], "locale_variants": {} }, { "sku": "52218", "brand": "SKF", "manufacturer_designation": "52218", "series": "52200-series", "type": "thrust_ball", "d_mm": 75, "D_mm": 135, "B_mm": 62, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 112, "static_load_kN": 290, "fatigue_load_limit_kN": 11.6, "reference_speed_rpm": 1500, "limiting_speed_rpm": 2000, "max_rpm": 2000, "weight_g": 3200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52218 is an ISO 104 double-direction thrust ball bearing, 75 mm bore and 135 mm OD on a flat housing seat, standing 62 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52218 is 75 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 75×135×62 mm (2.953×5.315×2.441 in), 30.0 mm radial section, C 112 kN, C0 290 kN, Pu 11.6 kN. reference speed 1,500 r/min (thermal) and limiting speed 2,000 r/min (mechanical), catalogue mass 3200 g. Bore-to-OD planning: OD 135 over bore 75 is a 1.80× step for this size, and the 62 mm height gives a bore/height ratio of 1.21; use these ratios when the housing recess around the 75 mm shaft is the first constraint. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.55 at the 2,000 r/min limiting speed raises the required axial preload to about 24.3 kN; the reference-speed value 13.6 kN is the thermal design point. Mass and section check: 3200 g inside the 75×135×62 mm outline leaves a 30.0 mm radial section, and the 290 kN static rating is 2.59× the dynamic rating — plan static safety and minimum preload against those figures. Load balance: C0 290 kN against C 112 kN gives a 2.59 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 11.6 kN enters the adjusted-life check. Light-load floor: Pu = 11.6 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52218; the number is 10 % of the 112 kN dynamic rating. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52218 is done separately per direction: if duty applies 112 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "crane travel and slewing drives", "winch and hoist reversal positions", "large lead-screw and press adjustment" ], "failure_modes": [ "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "track-edge spalling after the shaft washer seat is machined out of square and both rows share the tilt", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "washer face scoring from swarf trapped between the loose housing washer and its register", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "The central shaft washer takes the interference fit on the 75 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52200 unit has no alignment capacity.", "Service both cage sets together: replacing only the noisy side while leaving the worn 290 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 62 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52218 as the double flat pressed steel execution; other order numbers of the 52218 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52218?", "a": "The catalogue envelope is 75×135×62 mm, mass 3200 g; ratings C 112 kN / C0 290 kN / Pu 11.6 kN, reference speed 1,500 r/min (thermal) and limiting speed 2,000 r/min (mechanical)." }, { "q": "What does the designation 52218 mean?", "a": "note the bore of 52218 is 75 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "How is a vertical double-direction 52218 lubricated and retained?", "a": "Use an oil bath reaching the lower track plus a feed or oil level that serves the upper cage set, or a coherent heavy-base grease; positively retain both loose housing washers because gravity loads the upper stack differently at standstill." }, { "q": "Which fits and retention does 52218 need?", "a": "The central shaft washer takes an interference fit on the 75 mm shaft; both housing washers run loose in their registers and must be positively retained, especially on vertical shafts, where the upper washer and its cage set also need lubricant retained." } ], "cross_ref": [ { "equiv_sku": "52218", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52218" ], "locale_variants": {} }, { "sku": "52220", "brand": "SKF", "manufacturer_designation": "52220", "series": "52200-series", "type": "thrust_ball", "d_mm": 85, "D_mm": 150, "B_mm": 67, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 119, "static_load_kN": 325, "fatigue_load_limit_kN": 10.8, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 4200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 52200 series order number 52220 is a SKF double-direction thrust ball bearing for a 85 mm seat, built to ISO 104, with a flat housing seating surface, 85×150×67 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 85 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 85×150×67 mm (3.346×5.906×2.638 in), 32.5 mm radial section, C 119 kN, C0 325 kN, Pu 10.8 kN. reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical), catalogue mass 4200 g. Imperial cross-check for procurement drawings: 3.346 in bore, 5.906 in OD, 2.638 in height, and the 4200 g catalogue mass converts to 4.200 kg (148.1 oz). Speed-ratio note for this exact unit: the reference speed is 1,300 r/min against a 1,800 r/min limiting speed, a reference-to-limit ratio of 0.72. Bore-to-OD planning: OD 150 over bore 85 is a 1.76× step for this size, and the 67 mm height gives a bore/height ratio of 1.27; use these ratios when the housing recess around the 85 mm shaft is the first constraint. Light-load floor: Pu = 10.8 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52220; the number is 9 % of the 119 kN dynamic rating. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.62 at the 1,800 r/min limiting speed raises the required axial preload to about 27.7 kN; the reference-speed value 14.5 kN is the thermal design point. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 85 mm bore and 67 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 150 mm housing washers must remain free to slide during thermal movement.", "applications": [ "heavy reversing gearbox shafts", "vertical motors subject to start-up up-thrust", "winch and hoist reversal positions" ], "failure_modes": [ "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "thermal lock-up when differential expansion removes the end play of the tighter-loaded side", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "washer face scoring from swarf trapped between the loose housing washer and its register" ], "pitfalls": [ "Service both cage sets together: replacing only the noisy side while leaving the worn 325 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 67 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52200 unit has no alignment capacity.", "Do not replace a 52220 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 85×150 mm bore and OD.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52220 as the double flat pressed steel execution; other order numbers of the 52220 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52220?", "a": "Boundary dimensions to ISO 104: bore 85 mm, OD 150 mm, height 67 mm; weight 4200 g. Load figures from SKF 17000: dynamic 119 kN, static 325 kN, fatigue limit 10.8 kN; reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical)." }, { "q": "What does the designation 52220 mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 85 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "What static check governs crane-hook duty for 52220?", "a": "Hook and screw positions are usually sized on C0 (325 kN here) with the application's static safety factor against peak stationary or shock thrust, not on the 119 kN L10 figure — reversal frequency then decides whether the 52-series geometry is acceptable." }, { "q": "What minimum axial load applies to a double-direction bearing?", "a": "The Fam ≈ A·(n·dm/1000)² rule (factor A 0.62) applies to EACH direction: the momentarily unloaded side during slow reversal is the one that skids, so preload or balanced loading must keep both ball sets seated." } ], "cross_ref": [ { "equiv_sku": "52220", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52220" ], "locale_variants": {} }, { "sku": "52320", "brand": "SKF", "manufacturer_designation": "52320", "series": "52300-series", "type": "thrust_ball", "d_mm": 85, "D_mm": 170, "B_mm": 97, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 225, "static_load_kN": 570, "fatigue_load_limit_kN": 18.3, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1400, "max_rpm": 1400, "weight_g": 8950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52320 is an ISO 104 double-direction thrust ball bearing, 85 mm bore and 170 mm OD on a flat housing seat, standing 97 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52320 is 85 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 85×170×97 mm (3.346×6.693×3.819 in), 42.5 mm radial section, C 225 kN, C0 570 kN, Pu 18.3 kN. reference speed 1,000 r/min (thermal) and limiting speed 1,400 r/min (mechanical), catalogue mass 8950 g. Sizing arithmetic on the 85 mm bore: 225 kN C over the 42.5 mm radial section gives 5.3 kN per section millimetre, and the 97 mm stack height is 2.28× that section — proportions typical of a 52300 thrust section. Speed band width for this size is 400 r/min between reference and limiting (1.40× ratio); lubrication, preload and heat removal decide where inside that band 52320 can actually run. Imperial cross-check for procurement drawings: 3.346 in bore, 6.693 in OD, 3.819 in height, and the 8950 g catalogue mass converts to 8.950 kg (315.7 oz). Load balance: C0 570 kN against C 225 kN gives a 2.53 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 18.3 kN enters the adjusted-life check. Envelope economics: the 97 mm axial height over a 42.5 mm radial section yields 2.3 kN of dynamic capacity per height millimetre, and the bearing weighs 8950 g for 225 kN C — about 40 g per rated kN. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 85 mm bore and 97 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 170 mm housing washers must remain free to slide during thermal movement.", "applications": [ "crane travel and slewing drives", "large lead-screw and press adjustment", "winch and hoist reversal positions" ], "failure_modes": [ "track-edge spalling after the shaft washer seat is machined out of square and both rows share the tilt", "differential wear when one cage set loses lubrication first on a vertical mounting", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Each direction independently needs the minimum axial load (factor A 1.9): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "The central shaft washer takes the interference fit on the 85 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "Service both cage sets together: replacing only the noisy side while leaving the worn 570 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Do not replace a 52320 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 85×170 mm bore and OD.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52320 as the double flat pressed steel execution; other order numbers of the 52320 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52320?", "a": "The catalogue envelope is 85×170×97 mm, mass 8950 g; ratings C 225 kN / C0 570 kN / Pu 18.3 kN, reference speed 1,000 r/min (thermal) and limiting speed 1,400 r/min (mechanical)." }, { "q": "What does the designation 52320 mean?", "a": "note the bore of 52320 is 85 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "When should I choose 52-series flat instead of 54-series sphered?", "a": "Choose the flat 52-series when the housing register can be machined square to the shaft; choose the 54-series with two U seat washers when initial misalignment has to be accommodated on fabricated or less rigid structures." }, { "q": "Can it replace two single-direction 51-series bearings?", "a": "It replaces a mirrored pair functionally — one fit, one housing bore, factory-matched geometry — but its 97 mm height is not twice the single-bearing height and seat details differ, so the housing and cover must be re-drawn rather than swapped in place." } ], "cross_ref": [ { "equiv_sku": "52320", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52320" ], "locale_variants": {} }, { "sku": "52222", "brand": "SKF", "manufacturer_designation": "52222", "series": "52200-series", "type": "thrust_ball", "d_mm": 95, "D_mm": 160, "B_mm": 67, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 125, "static_load_kN": 365, "fatigue_load_limit_kN": 11.6, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 4650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52222 is an ISO 104 double-direction thrust ball bearing, 95 mm bore and 160 mm OD on a flat housing seat, standing 67 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52222 is 95 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 95×160×67 mm (3.74×6.299×2.638 in), 32.5 mm radial section, C 125 kN, C0 365 kN, Pu 11.6 kN. reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical), catalogue mass 4650 g. Sizing arithmetic on the 95 mm bore: 125 kN C over the 32.5 mm radial section gives 3.8 kN per section millimetre, and the 67 mm stack height is 2.06× that section — proportions typical of a 52200 thrust section. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 1,800 r/min while thermal balance under catalogue load sets the 1,300 r/min reference; at dm ≈ 127.5 mm the corresponding dn is approximately 230k mm·r/min. Minimum-load arithmetic: with dm ≈ 127.5 mm and factor A 0.79, Fam ≈ A·(n·dm/1000)² at the 1,300 r/min reference speed is about 21.7 kN for 52222; below that preload the balls skid and smear the tracks. Stack/annulus proportions: the 67 mm axial stack over the 13,018 mm² washer annulus gives 5.15 mm of height per annular square millimetre ×10⁻³, and at 4650 g the bearing holds about 78.5 kN of C0 per kilogram. Envelope economics: the 67 mm axial height over a 32.5 mm radial section yields 1.9 kN of dynamic capacity per height millimetre, and the bearing weighs 4650 g for 125 kN C — about 37 g per rated kN. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52222 is done separately per direction: if duty applies 125 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "crane travel and slewing drives", "winch and hoist reversal positions", "large lead-screw and press adjustment" ], "failure_modes": [ "cage-set loss during handling because the five components separate as soon as the unit leaves the recess", "brinelling of one track pair from a static reversing shock concentrated on a single side", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 67 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "The double-direction 52222 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 95 mm shaft axially in both directions instead of a mirrored pair.", "Each direction independently needs the minimum axial load (factor A 0.79): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 1,800 r/min even a small thermal thrust preload smears the hottest track.", "The 125/365 kN figures belong to 52222 specifically (the double flat pressed steel execution of 52222); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52222?", "a": "The catalogue envelope is 95×160×67 mm, mass 4650 g; ratings C 125 kN / C0 365 kN / Pu 11.6 kN, reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical)." }, { "q": "What does the designation 52222 mean?", "a": "note the bore of 52222 is 95 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "How is the double-direction 52222 constructed?", "a": "One central shaft washer with tracks on both faces and a ground bore, two housing washers facing outwards and two independent ball-cage assemblies — all supplied as one 95×160×67 mm unit locating the shaft axially in both directions." }, { "q": "When should I choose 52-series flat instead of 54-series sphered?", "a": "Choose the flat 52-series when the housing register can be machined square to the shaft; choose the 54-series with two U seat washers when initial misalignment has to be accommodated on fabricated or less rigid structures." } ], "cross_ref": [ { "equiv_sku": "52222", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52222" ], "locale_variants": {} }, { "sku": "52224", "brand": "SKF", "manufacturer_designation": "52224", "series": "52200-series", "type": "thrust_ball", "d_mm": 100, "D_mm": 170, "B_mm": 68, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 127, "static_load_kN": 390, "fatigue_load_limit_kN": 11.8, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1700, "max_rpm": 1700, "weight_g": 5250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52224 is an ISO 104 double-direction thrust ball bearing, 100 mm bore and 170 mm OD on a flat housing seat, standing 68 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52224 is 100 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 100×170×68 mm (3.937×6.693×2.677 in), 35.0 mm radial section, C 127 kN, C0 390 kN, Pu 11.8 kN. reference speed 1,200 r/min (thermal) and limiting speed 1,700 r/min (mechanical), catalogue mass 5250 g. Section proportions: the 35.0 mm radial section compares with 100 mm of bore (section/bore ≈ 0.35) and the 68 mm height is 1.94× that section — the proportions that identify the 52200 envelope at a glance. Selection figures for 52224: the C0/C ratio is 3.07, Pu 11.8 kN is about 9 % of C, and the catalogue mass works out to roughly 53 g per millimetre of bore; the printed minimum-load factor is A 1. Imperial cross-check for procurement drawings: 3.937 in bore, 6.693 in OD, 2.677 in height, and the 5250 g catalogue mass converts to 5.250 kg (185.2 oz). Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 1 at the 1,700 r/min limiting speed raises the required axial preload to about 52.7 kN; the reference-speed value 26.2 kN is the thermal design point. Mass and section check: 5250 g inside the 100×170×68 mm outline leaves a 35.0 mm radial section, and the 390 kN static rating is 3.07× the dynamic rating — plan static safety and minimum preload against those figures. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. At 100 mm bore and 68 mm overall height the unit drops into one recess where a mirrored single-direction pair would need two seats; both loose 170 mm housing washers must remain free to slide during thermal movement.", "applications": [ "heavy reversing gearbox shafts", "winch and hoist reversal positions", "crane travel and slewing drives" ], "failure_modes": [ "track-edge spalling after the shaft washer seat is machined out of square and both rows share the tilt", "differential wear when one cage set loses lubrication first on a vertical mounting", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "overheating from grease overfill churning inside a sealed housing recess with no escape volume" ], "pitfalls": [ "Service both cage sets together: replacing only the noisy side while leaving the worn 390 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 68 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52200 unit has no alignment capacity.", "Do not replace a 52224 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 100×170 mm bore and OD.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52224 as the double flat pressed steel execution; other order numbers of the 52224 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52224?", "a": "The catalogue envelope is 100×170×68 mm, mass 5250 g; ratings C 127 kN / C0 390 kN / Pu 11.8 kN, reference speed 1,200 r/min (thermal) and limiting speed 1,700 r/min (mechanical)." }, { "q": "What does the designation 52224 mean?", "a": "note the bore of 52224 is 100 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "Which fits and retention does 52224 need?", "a": "The central shaft washer takes an interference fit on the 100 mm shaft; both housing washers run loose in their registers and must be positively retained, especially on vertical shafts, where the upper washer and its cage set also need lubricant retained." }, { "q": "What static check governs crane-hook duty for 52224?", "a": "Hook and screw positions are usually sized on C0 (390 kN here) with the application's static safety factor against peak stationary or shock thrust, not on the 127 kN L10 figure — reversal frequency then decides whether the 52-series geometry is acceptable." } ], "cross_ref": [ { "equiv_sku": "52224", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52224" ], "locale_variants": {} }, { "sku": "52226", "brand": "SKF", "manufacturer_designation": "52226", "series": "52200-series", "type": "thrust_ball", "d_mm": 110, "D_mm": 190, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 182, "static_load_kN": 585, "fatigue_load_limit_kN": 16.6, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1500, "max_rpm": 1500, "weight_g": 8000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52226 is an ISO 104 double-direction thrust ball bearing, 110 mm bore and 190 mm OD on a flat housing seat, standing 80 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52226 is 110 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 110×190×80 mm (4.331×7.48×3.15 in), 40.0 mm radial section, C 182 kN, C0 585 kN, Pu 16.6 kN. reference speed 1,100 r/min (thermal) and limiting speed 1,500 r/min (mechanical), catalogue mass 8000 g. Speed band width for this size is 400 r/min between reference and limiting (1.36× ratio); lubrication, preload and heat removal decide where inside that band 52226 can actually run. Track-circle loading: per millimetre of mean track circumference the 182 kN dynamic rating corresponds to roughly 0.39 kN/mm of π·dm track, a useful comparison against the other dimension series of the 110 mm bore. Mass and section check: 8000 g inside the 110×190×80 mm outline leaves a 40.0 mm radial section, and the 585 kN static rating is 3.21× the dynamic rating — plan static safety and minimum preload against those figures. Pitch-diameter arithmetic: dm = (110+190)/2 = 150.0 mm; at the 1,500 r/min limiting speed that corresponds to roughly 225k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Imperial cross-check for procurement drawings: 4.331 in bore, 7.48 in OD, 3.15 in height, and the 8000 g catalogue mass converts to 8.000 kg (282.2 oz). Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52226 is done separately per direction: if duty applies 182 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "vertical motors subject to start-up up-thrust", "heavy reversing gearbox shafts", "crane travel and slewing drives" ], "failure_modes": [ "assembly damage when the central shaft washer is fitted reversed or the two outward-facing housing washers are swapped", "brinelling of one track pair from a static reversing shock concentrated on a single side", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 80 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "The double-direction 52226 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 110 mm shaft axially in both directions instead of a mirrored pair.", "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 1,500 r/min even a small thermal thrust preload smears the hottest track.", "Service both cage sets together: replacing only the noisy side while leaving the worn 585 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Ordering discipline for 52226: the catalogue page quotes 52226 and its 182/585 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52226?", "a": "The catalogue envelope is 110×190×80 mm, mass 8000 g; ratings C 182 kN / C0 585 kN / Pu 16.6 kN, reference speed 1,100 r/min (thermal) and limiting speed 1,500 r/min (mechanical)." }, { "q": "What does the designation 52226 mean?", "a": "note the bore of 52226 is 110 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "When should I choose 52-series flat instead of 54-series sphered?", "a": "Choose the flat 52-series when the housing register can be machined square to the shaft; choose the 54-series with two U seat washers when initial misalignment has to be accommodated on fabricated or less rigid structures." }, { "q": "Can it replace two single-direction 51-series bearings?", "a": "It replaces a mirrored pair functionally — one fit, one housing bore, factory-matched geometry — but its 80 mm height is not twice the single-bearing height and seat details differ, so the housing and cover must be re-drawn rather than swapped in place." } ], "cross_ref": [ { "equiv_sku": "52226", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52226" ], "locale_variants": {} }, { "sku": "52228", "brand": "SKF", "manufacturer_designation": "52228", "series": "52200-series", "type": "thrust_ball", "d_mm": 120, "D_mm": 200, "B_mm": 81, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 190, "static_load_kN": 620, "fatigue_load_limit_kN": 17.6, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1400, "max_rpm": 1400, "weight_g": 8650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "52228 is SKF's 120 mm-bore double-direction thrust ball bearing in the 52200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 120×200×81 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 120 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 120×200×81 mm (4.724×7.874×3.189 in), 40.0 mm radial section, C 190 kN, C0 620 kN, Pu 17.6 kN. reference speed 1,000 r/min (thermal) and limiting speed 1,400 r/min (mechanical), catalogue mass 8650 g. Minimum-load arithmetic: with dm ≈ 160.0 mm and factor A 2, Fam ≈ A·(n·dm/1000)² at the 1,000 r/min reference speed is about 51.2 kN for 52228; below that preload the balls skid and smear the tracks. Selection figures for 52228: the C0/C ratio is 3.26, Pu 17.6 kN is about 9 % of C, and the catalogue mass works out to roughly 72 g per millimetre of bore; the printed minimum-load factor is A 2. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 2 at the 1,400 r/min limiting speed raises the required axial preload to about 100.4 kN; the reference-speed value 51.2 kN is the thermal design point. Stack/annulus proportions: the 81 mm axial stack over the 20,106 mm² washer annulus gives 4.03 mm of height per annular square millimetre ×10⁻³, and at 8650 g the bearing holds about 71.7 kN of C0 per kilogram. Speed-ratio note for this exact unit: the reference speed is 1,000 r/min against a 1,400 r/min limiting speed, a reference-to-limit ratio of 0.71. Double-direction order-number note: the unit is built around one central shaft washer with a ground bore and tracks on both faces, flanked by two housing washers and two independent ball-cage assemblies; observe the assembly orientation (the two housing washers face outwards) and note that a 52-series unit replaces a mirrored pair of 51-series bearings only after the stack height and seat drawings are re-checked. Life accounting for 52228 is done separately per direction: if duty applies 190 kN C predominantly one way, the idle side's skid risk — not the loaded side's L10 — usually sets the relubrication and preload interval.", "applications": [ "heavy converter tilt screws", "large marine reversing drives", "primary mill adjustment screws under reversing thrust" ], "failure_modes": [ "cover-induced thrust preload when the end cover is torqued solid instead of leaving the catalogue axial freedom", "differential wear when one cage set loses lubrication first on a vertical mounting", "unbalanced loading of the two cage sets when one load direction dominates service life and the idle set skids", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 1,400 r/min even a small thermal thrust preload smears the hottest track.", "Service both cage sets together: replacing only the noisy side while leaving the worn 620 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 81 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "Do not replace a 52228 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 120×200 mm bore and OD.", "Ordering discipline for 52228: the catalogue page quotes 52228 and its 190/620 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52228?", "a": "52228 measures 120 mm bore × 200 mm OD × 81 mm bearing height (4.724 × 7.874 × 3.189 in), mass about 8650 g. SKF 17000 ratings: C 190 kN, C0 620 kN, Pu 17.6 kN, reference speed 1,000 r/min (thermal) and limiting speed 1,400 r/min (mechanical)." }, { "q": "What does the designation 52228 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 120 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "Which fits and retention does 52228 need?", "a": "The central shaft washer takes an interference fit on the 120 mm shaft; both housing washers run loose in their registers and must be positively retained, especially on vertical shafts, where the upper washer and its cage set also need lubricant retained." }, { "q": "What static check governs crane-hook duty for 52228?", "a": "Hook and screw positions are usually sized on C0 (620 kN here) with the application's static safety factor against peak stationary or shock thrust, not on the 190 kN L10 figure — reversal frequency then decides whether the 52-series geometry is acceptable." } ], "cross_ref": [ { "equiv_sku": "52228", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52228" ], "locale_variants": {} }, { "sku": "52230-M", "brand": "SKF", "manufacturer_designation": "52230 M", "series": "52200-series", "type": "thrust_ball", "d_mm": 130, "D_mm": 215, "B_mm": 89, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 238, "static_load_kN": 800, "fatigue_load_limit_kN": 22, "reference_speed_rpm": 950, "limiting_speed_rpm": 1300, "max_rpm": 1300, "weight_g": 11500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "52230 M is SKF's 130 mm-bore double-direction thrust ball bearing in the 52200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 130×215×89 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 130 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 130×215×89 mm (5.118×8.465×3.504 in), 42.5 mm radial section, C 238 kN, C0 800 kN, Pu 22 kN. reference speed 950 r/min (thermal) and limiting speed 1,300 r/min (mechanical), catalogue mass 11500 g. Track-circle loading: per millimetre of mean track circumference the 238 kN dynamic rating corresponds to roughly 0.44 kN/mm of π·dm track, a useful comparison against the other dimension series of the 130 mm bore. At the printed limiting speed of 1,300 r/min the mean pitch diameter dm ≈ 172.5 mm implies a dn value around 224k mm·r/min; the 950 r/min reference speed is the thermal-planning value under catalogue load. Imperial cross-check for procurement drawings: 5.118 in bore, 8.465 in OD, 3.504 in height, and the 11500 g catalogue mass converts to 11.500 kg (405.6 oz). Rating split for documentation: dynamic 238 kN (L10 life), static 800 kN (safety factor s0), fatigue limit 22 kN (adjusted life) — three different uses of three different numbers for 52230 M, none interchangeable with another. Speed-ratio note for this exact unit: the reference speed is 950 r/min against a 1,300 r/min limiting speed, a reference-to-limit ratio of 0.73. Heavy double-direction note: the M suffix on a 52/54-series bearing means both ball-cage assemblies are machined brass and ball-centred for the largest bidirectional positions; both cage sets share the same lubrication requirement, so the oil or grease feed must reach the upper as well as the lower track on vertical shafts. The M suffix means BOTH cage sets of the 89 mm stack are machined brass; spare-part orders of one side should still be placed as the complete 52230 M unit, because mixed cage executions in one double-direction stack are not a catalogue configuration.", "applications": [ "large hydraulic-press guidance", "large marine reversing drives", "offshore winch reversal drums" ], "failure_modes": [ "thermal lock-up when differential expansion removes the end play of the tighter-loaded side", "cage-set loss during handling because the five components separate as soon as the unit leaves the recess", "upper brass-cage starvation on a vertical shaft whose lubricant feeds only the lower track pair", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Service both cage sets together: replacing only the noisy side while leaving the worn 800 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 89 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 1,300 r/min even a small thermal thrust preload smears the hottest track.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52200 unit has no alignment capacity.", "Ordering discipline for 52230: the catalogue page quotes 52230 M and its 238/800 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52230-M?", "a": "52230 M measures 130 mm bore × 215 mm OD × 89 mm bearing height (5.118 × 8.465 × 3.504 in), mass about 11500 g. SKF 17000 ratings: C 238 kN, C0 800 kN, Pu 22 kN, reference speed 950 r/min (thermal) and limiting speed 1,300 r/min (mechanical)." }, { "q": "What does the designation 52230 M mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 130 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "How is the double-direction 52230 constructed?", "a": "One central shaft washer with tracks on both faces and a ground bore, two housing washers facing outwards and two independent ball-cage assemblies — all supplied as one 130×215×89 mm unit locating the shaft axially in both directions." }, { "q": "When should I choose 52-series flat instead of 54-series sphered?", "a": "Choose the flat 52-series when the housing register can be machined square to the shaft; choose the 54-series with two U seat washers when initial misalignment has to be accommodated on fabricated or less rigid structures." } ], "cross_ref": [ { "equiv_sku": "52230", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52230-M", "52230 M" ], "locale_variants": {} }, { "sku": "52232-M", "brand": "SKF", "manufacturer_designation": "52232 M", "series": "52200-series", "type": "thrust_ball", "d_mm": 140, "D_mm": 225, "B_mm": 90, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 238, "static_load_kN": 830, "fatigue_load_limit_kN": 22.4, "reference_speed_rpm": 900, "limiting_speed_rpm": 1300, "max_rpm": 1300, "weight_g": 12000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52232 M is an ISO 104 double-direction thrust ball bearing, 140 mm bore and 225 mm OD on a flat housing seat, standing 90 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52232 M is 140 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. Envelope 140×225×90 mm (5.512×8.858×3.543 in), 42.5 mm radial section, C 238 kN, C0 830 kN, Pu 22.4 kN. reference speed 900 r/min (thermal) and limiting speed 1,300 r/min (mechanical), catalogue mass 12000 g. Speed band width for this size is 400 r/min between reference and limiting (1.44× ratio); lubrication, preload and heat removal decide where inside that band 52232 M can actually run. Bore-to-OD planning: OD 225 over bore 140 is a 1.61× step for this size, and the 90 mm height gives a bore/height ratio of 1.56; use these ratios when the housing recess around the 140 mm shaft is the first constraint. Load balance: C0 830 kN against C 238 kN gives a 3.49 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 22.4 kN enters the adjusted-life check. Rating split for documentation: dynamic 238 kN (L10 life), static 830 kN (safety factor s0), fatigue limit 22.4 kN (adjusted life) — three different uses of three different numbers for 52232 M, none interchangeable with another. Stack/annulus proportions: the 90 mm axial stack over the 24,367 mm² washer annulus gives 3.69 mm of height per annular square millimetre ×10⁻³, and at 12000 g the bearing holds about 69.2 kN of C0 per kilogram. Heavy double-direction note: the M suffix on a 52/54-series bearing means both ball-cage assemblies are machined brass and ball-centred for the largest bidirectional positions; both cage sets share the same lubrication requirement, so the oil or grease feed must reach the upper as well as the lower track on vertical shafts. With 12000 g rotating partially with the shaft, check the rotor-balance influence of the central shaft washer at speeds approaching 1,300 r/min; the two loose washers do not rotate and contribute no imbalance.", "applications": [ "large marine reversing drives", "primary mill adjustment screws under reversing thrust", "offshore winch reversal drums" ], "failure_modes": [ "track-edge spalling after the shaft washer seat is machined out of square and both rows share the tilt", "differential wear when one cage set loses lubrication first on a vertical mounting", "upper brass-cage starvation on a vertical shaft whose lubricant feeds only the lower track pair", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 1,300 r/min even a small thermal thrust preload smears the hottest track.", "Service both cage sets together: replacing only the noisy side while leaving the worn 830 kN opposite track in place reproduces the failure within weeks — inspect both shaft-washer faces and both loose washers at removal.", "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52200 unit has no alignment capacity.", "Do not replace a 52232 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 140×225 mm bore and OD.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52232 M as the double flat brass execution; other order numbers of the 52232 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52232-M?", "a": "The catalogue envelope is 140×225×90 mm, mass 12000 g; ratings C 238 kN / C0 830 kN / Pu 22.4 kN, reference speed 900 r/min (thermal) and limiting speed 1,300 r/min (mechanical)." }, { "q": "What does the designation 52232 M mean?", "a": "note the bore of 52232 M is 140 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "What minimum axial load applies to a double-direction bearing?", "a": "The Fam ≈ A·(n·dm/1000)² rule (factor A 3.8) applies to EACH direction: the momentarily unloaded side during slow reversal is the one that skids, so preload or balanced loading must keep both ball sets seated." }, { "q": "How is the double-direction 52232 constructed?", "a": "One central shaft washer with tracks on both faces and a ground bore, two housing washers facing outwards and two independent ball-cage assemblies — all supplied as one 140×225×90 mm unit locating the shaft axially in both directions." } ], "cross_ref": [ { "equiv_sku": "52232", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52232-M", "52232 M" ], "locale_variants": {} }, { "sku": "52234-M", "brand": "SKF", "manufacturer_designation": "52234 M", "series": "52200-series", "type": "thrust_ball", "d_mm": 150, "D_mm": 240, "B_mm": 97, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 270, "static_load_kN": 930, "fatigue_load_limit_kN": 24, "reference_speed_rpm": 850, "limiting_speed_rpm": 1200, "max_rpm": 1200, "weight_g": 15000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 52234 M is an ISO 104 double-direction thrust ball bearing, 150 mm bore and 240 mm OD on a flat housing seat, standing 97 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 52234 M is 150 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. Envelope 150×240×97 mm (5.906×9.449×3.819 in), 45.0 mm radial section, C 270 kN, C0 930 kN, Pu 24 kN. reference speed 850 r/min (thermal) and limiting speed 1,200 r/min (mechanical), catalogue mass 15000 g. Speed planning separates the two ceilings mechanically: the pressed brass cage and balls tolerate 1,200 r/min while thermal balance under catalogue load sets the 850 r/min reference; at dm ≈ 195.0 mm the corresponding dn is approximately 234k mm·r/min. Static-first selection data: 930 kN C0 spread across the 97 mm stack gives 9.6 kN of static rating per height millimetre, and the 15000 g mass/C0 ratio is about 16 g per static kN — crane-hook and screw positions are normally sized on these two figures. Light-load floor: Pu = 24 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 52234 M; the number is 9 % of the 270 kN dynamic rating. Load balance: C0 930 kN against C 270 kN gives a 3.44 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 24 kN enters the adjusted-life check. Speed-ratio note for this exact unit: the reference speed is 850 r/min against a 1,200 r/min limiting speed, a reference-to-limit ratio of 0.71. Heavy double-direction note: the M suffix on a 52/54-series bearing means both ball-cage assemblies are machined brass and ball-centred for the largest bidirectional positions; both cage sets share the same lubrication requirement, so the oil or grease feed must reach the upper as well as the lower track on vertical shafts. The M suffix means BOTH cage sets of the 97 mm stack are machined brass; spare-part orders of one side should still be placed as the complete 52234 M unit, because mixed cage executions in one double-direction stack are not a catalogue configuration.", "applications": [ "large hydraulic-press guidance", "large marine reversing drives", "primary mill adjustment screws under reversing thrust" ], "failure_modes": [ "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "track-edge spalling after the shaft washer seat is machined out of square and both rows share the tilt", "upper brass-cage starvation on a vertical shaft whose lubricant feeds only the lower track pair", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Do not replace a 52234 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 150×240 mm bore and OD.", "Torque the cover to leave the catalogue axial freedom, never solid: a clamped double-direction stack cannot float to its thermal position, and at 1,200 r/min even a small thermal thrust preload smears the hottest track.", "Each direction independently needs the minimum axial load (factor A 5.4): the side that is momentarily unloaded during slow reversal skids first, so arrange preload or symmetry rather than assuming the loaded side drives the idle side.", "The central shaft washer takes the interference fit on the 150 mm shaft while both outer housing washers run loose in their registers; both loose washers need positive axial retention on vertical shafts.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 52234 M as the double flat brass execution; other order numbers of the 52234 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52234-M?", "a": "The catalogue envelope is 150×240×97 mm, mass 15000 g; ratings C 270 kN / C0 930 kN / Pu 24 kN, reference speed 850 r/min (thermal) and limiting speed 1,200 r/min (mechanical)." }, { "q": "What does the designation 52234 M mean?", "a": "note the bore of 52234 M is 150 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "How is a vertical double-direction 52234 lubricated and retained?", "a": "Use an oil bath reaching the lower track plus a feed or oil level that serves the upper cage set, or a coherent heavy-base grease; positively retain both loose housing washers because gravity loads the upper stack differently at standstill." }, { "q": "Which fits and retention does 52234-M need?", "a": "The central shaft washer takes an interference fit on the 150 mm shaft; both housing washers run loose in their registers and must be positively retained, especially on vertical shafts, where the upper washer and its cage set also need lubricant retained." } ], "cross_ref": [ { "equiv_sku": "52234", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52234-M", "52234 M" ], "locale_variants": {} }, { "sku": "52236-M", "brand": "SKF", "manufacturer_designation": "52236 M", "series": "52200-series", "type": "thrust_ball", "d_mm": 150, "D_mm": 250, "B_mm": 98, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 302, "static_load_kN": 1120, "fatigue_load_limit_kN": 28.5, "reference_speed_rpm": 800, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 16000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "52236 M is SKF's 150 mm-bore double-direction thrust ball bearing in the 52200 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 150×250×98 mm. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 150 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 150×250×98 mm (5.906×9.843×3.858 in), 50.0 mm radial section, C 302 kN, C0 1120 kN, Pu 28.5 kN. reference speed 800 r/min (thermal) and limiting speed 1,100 r/min (mechanical), catalogue mass 16000 g. Sizing arithmetic on the 150 mm bore: 302 kN C over the 50.0 mm radial section gives 6.0 kN per section millimetre, and the 98 mm stack height is 1.96× that section — proportions typical of a 52200 thrust section. Section proportions: the 50.0 mm radial section compares with 150 mm of bore (section/bore ≈ 0.33) and the 98 mm height is 1.96× that section — the proportions that identify the 52200 envelope at a glance. Mass and section check: 16000 g inside the 150×250×98 mm outline leaves a 50.0 mm radial section, and the 1120 kN static rating is 3.71× the dynamic rating — plan static safety and minimum preload against those figures. Stack/annulus proportions: the 98 mm axial stack over the 31,416 mm² washer annulus gives 3.12 mm of height per annular square millimetre ×10⁻³, and at 16000 g the bearing holds about 70.0 kN of C0 per kilogram. Envelope economics: the 98 mm axial height over a 50.0 mm radial section yields 3.1 kN of dynamic capacity per height millimetre, and the bearing weighs 16000 g for 302 kN C — about 53 g per rated kN. Heavy double-direction note: the M suffix on a 52/54-series bearing means both ball-cage assemblies are machined brass and ball-centred for the largest bidirectional positions; both cage sets share the same lubrication requirement, so the oil or grease feed must reach the upper as well as the lower track on vertical shafts. With 16000 g rotating partially with the shaft, check the rotor-balance influence of the central shaft washer at speeds approaching 1,100 r/min; the two loose washers do not rotate and contribute no imbalance.", "applications": [ "large hydraulic-press guidance", "large marine reversing drives", "offshore winch reversal drums" ], "failure_modes": [ "thermal lock-up when differential expansion removes the end play of the tighter-loaded side", "ball skidding on the momentarily unloaded side during rapid thrust reversal below the minimum load", "upper brass-cage starvation on a vertical shaft whose lubricant feeds only the lower track pair", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Where shaft and housing cannot be kept square, the sphered 54-series execution of the same bore with two U seat washers is the self-aligning counterpart; the flat 52200 unit has no alignment capacity.", "Do not replace a 52236 with two single-direction 51-series bearings without re-checking the arrangement: envelope heights, seat details and catalogue ratings differ, even at the same 150×250 mm bore and OD.", "Observe the stack order at fitting: shaft washer central, the two housing washers facing outwards with a cage set on each side; the 98 mm total height is not twice a single-direction bearing height, so reuse of old cover dimensions is a trap.", "The double-direction 52236 is one central shaft washer with tracks on both faces, two housing washers and two ball-cage assemblies — a single unit locating the 150 mm shaft axially in both directions instead of a mirrored pair.", "Ordering discipline for 52236: the catalogue page quotes 52236 M and its 302/1120 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 52236-M?", "a": "52236 M measures 150 mm bore × 250 mm OD × 98 mm bearing height (5.906 × 9.843 × 3.858 in), mass about 16000 g. SKF 17000 ratings: C 302 kN, C0 1120 kN, Pu 28.5 kN, reference speed 800 r/min (thermal) and limiting speed 1,100 r/min (mechanical)." }, { "q": "What does the designation 52236 M mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 150 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. 5 = thrust ball bearing, 2 = double direction with flat seating surfaces." }, { "q": "How is the double-direction 52236 constructed?", "a": "One central shaft washer with tracks on both faces and a ground bore, two housing washers facing outwards and two independent ball-cage assemblies — all supplied as one 150×250×98 mm unit locating the shaft axially in both directions." }, { "q": "When should I choose 52-series flat instead of 54-series sphered?", "a": "Choose the flat 52-series when the housing register can be machined square to the shaft; choose the 54-series with two U seat washers when initial misalignment has to be accommodated on fabricated or less rigid structures." } ], "cross_ref": [ { "equiv_sku": "52236", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "52236-M", "52236 M" ], "locale_variants": {} }, { "sku": "54306", "brand": "SKF", "manufacturer_designation": "54306", "series": "54300-series", "type": "thrust_ball", "d_mm": 25, "D_mm": 60, "B_mm": 41.3, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.8, "static_load_kN": 65.5, "fatigue_load_limit_kN": 2.4, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 580, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "54306 is SKF's 25 mm-bore double-direction thrust ball bearing in the 54300 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 25×60×41.3 mm U 306 seat washer companion included in the mounted H1 dimension. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 25 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 25×60×41.3 mm (0.984×2.362×1.626 in), 17.5 mm radial section, C 35.8 kN, C0 65.5 kN, Pu 2.4 kN. Mounted height H1 46 mm includes the U 306 seat washer; the bearing alone is 41.3 mm high. reference speed 2,800 r/min (thermal) and limiting speed 3,800 r/min (mechanical), catalogue mass 580 g. Speed band width for this size is 1,000 r/min between reference and limiting (1.36× ratio); lubrication, preload and heat removal decide where inside that band 54306 can actually run. Capacity density: 35.8 kN C from 0.580 kg of bearing steel gives about 61.7 kN per kilogram; static density is correspondingly 112.9 kN/kg at C0 65.5 kN. Imperial cross-check for procurement drawings: 0.984 in bore, 2.362 in OD, 1.626 in height, and the 580 g catalogue mass converts to 0.580 kg (20.5 oz). Stack/annulus proportions: the 41.3 mm axial stack over the 2,337 mm² washer annulus gives 17.67 mm of height per annular square millimetre ×10⁻³, and at 580 g the bearing holds about 112.9 kN of C0 per kilogram. Pitch-diameter arithmetic: dm = (25+60)/2 = 42.5 mm; at the 3,800 r/min limiting speed that corresponds to roughly 162k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Bidirectional self-aligning note: TWO U seat washers are required for this order number, one behind each housing washer, and the catalogue H1 height includes them on both sides of the stack; the spherical interfaces accept initial misalignment in either load direction but are not pivots for continuous oscillation. Bill of materials for this page is 54306 plus TWO × U 306; the 46 mm H1 stack sits in a housing whose two register faces should be machined in one clamping to keep both spherical axes coincident.", "applications": [ "medium screw jacks loaded in both directions", "agricultural reversing linkage pivots", "bidirectional crane-hook and swivel positions with deflecting structure" ], "failure_modes": [ "cage-set loss during handling because the five components separate as soon as the unit leaves the recess", "differential wear when one cage set loses lubrication first on a vertical mounting", "tilted running after a mismatched U washer leaves only a narrow band of spherical contact", "one-side spherical seizure after grit fills the interface of the U washer on the less-loaded side", "washer face scoring from swarf trapped between the loose housing washer and its register", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "The two spherical interfaces accommodate initial misalignment in either load direction but must stay clean, greased and static — continuous rocking frets the sphered contacts of even the 65.5 kN static-rated set.", "Order TWO seat washers for 54306 — the designation U 306 pairs with one side and a second U washer (same number) with the other; the catalogue 46 mm H1 includes both.", "Replacement ordering is THREE numbers: 54306 plus two pieces of U 306; quoting only the bearing leaves the sphered backs running on bare registers.", "Assembly is a five-component stack (central shaft washer, two cage sets, two sphered housing washers) plus the two U seat washers in the housing registers; dry-build the arrangement by hand first to confirm both sides swivel freely.", "The 35.8/65.5 kN figures belong to 54306 specifically (the double sphered pressed steel execution of 54306); suffixed, sphered and counterpart-series order numbers are separate articles, and U 306 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 54306?", "a": "54306 measures 25 mm bore × 60 mm OD × 41.3 mm bearing height (0.984 × 2.362 × 1.626 in), or 46 mm mounted H1 including the U 306 seat washer, mass about 580 g. SKF 17000 ratings: C 35.8 kN, C0 65.5 kN, Pu 2.4 kN, reference speed 2,800 r/min (thermal) and limiting speed 3,800 r/min (mechanical)." }, { "q": "What does the designation 54306 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 25 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 4 = double direction with sphered seating surfaces." }, { "q": "Does the spherical seat work while the shaft rocks continuously?", "a": "No — it accommodates initial static misalignment only. Continuous oscillation frets the sphered contacts even with C0 65.5 kN in reserve; keep the interfaces greased and clean and design genuine pivots separately." }, { "q": "What loads can 54306 take?", "a": "Pure axial load in both directions: C 35.8 kN, C0 65.5 kN, Pu 2.4 kN, with the same minimum-load rule (factor A 0.026) in each direction; radial load is excluded." } ], "cross_ref": [ { "equiv_sku": "54306", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "54306", "54306 + U 306" ], "locale_variants": {} }, { "sku": "54207", "brand": "SKF", "manufacturer_designation": "54207", "series": "54200-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 62, "B_mm": 37.8, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 73.5, "fatigue_load_limit_kN": 2.7, "reference_speed_rpm": 2800, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 530, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "54207 is SKF's 30 mm-bore double-direction thrust ball bearing in the 54200 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 30×62×37.8 mm U 207 seat washer companion included in the mounted H1 dimension. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 30 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 30×62×37.8 mm (1.181×2.441×1.488 in), 16.0 mm radial section, C 35.1 kN, C0 73.5 kN, Pu 2.7 kN. Mounted height H1 42 mm includes the U 207 seat washer; the bearing alone is 37.8 mm high. reference speed 2,800 r/min (thermal) and limiting speed 4,000 r/min (mechanical), catalogue mass 530 g. Bore-to-OD planning: OD 62 over bore 30 is a 2.07× step for this size, and the 37.8 mm height gives a bore/height ratio of 0.79; use these ratios when the housing recess around the 30 mm shaft is the first constraint. Capacity density: 35.1 kN C from 0.530 kg of bearing steel gives about 66.2 kN per kilogram; static density is correspondingly 138.7 kN/kg at C0 73.5 kN. Load balance: C0 73.5 kN against C 35.1 kN gives a 2.09 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 2.7 kN enters the adjusted-life check. Light-load floor: Pu = 2.7 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 54207; the number is 8 % of the 35.1 kN dynamic rating. Static-first selection data: 73.5 kN C0 spread across the 37.8 mm stack gives 1.9 kN of static rating per height millimetre, and the 530 g mass/C0 ratio is about 7 g per static kN — crane-hook and screw positions are normally sized on these two figures. Bidirectional self-aligning note: TWO U seat washers are required for this order number, one behind each housing washer, and the catalogue H1 height includes them on both sides of the stack; the spherical interfaces accept initial misalignment in either load direction but are not pivots for continuous oscillation. At 30×62×37.8 mm the bearing carries C0 73.5 kN bidirectionally, but the two U interfaces share that load only if each is free to seat; torque the covers so the 4.2 mm-per-side washer steps are not pre-clamped.", "applications": [ "medium screw jacks loaded in both directions", "agricultural reversing linkage pivots", "bidirectional crane-hook and swivel positions with deflecting structure" ], "failure_modes": [ "thermal lock-up when differential expansion removes the end play of the tighter-loaded side", "cage-set loss during handling because the five components separate as soon as the unit leaves the recess", "fretting corrosion in the spherical interface under oscillation with no grease between washer and seat", "one-side spherical seizure after grit fills the interface of the U washer on the less-loaded side", "washer face scoring from swarf trapped between the loose housing washer and its register", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "Assembly is a five-component stack (central shaft washer, two cage sets, two sphered housing washers) plus the two U seat washers in the housing registers; dry-build the arrangement by hand first to confirm both sides swivel freely.", "Minimum load factor A 0.028 applies to both load directions, and both brass pressed cage sets need lubricant reaching the upper track on a vertical shaft.", "Replacement ordering is THREE numbers: 54207 plus two pieces of U 207; quoting only the bearing leaves the sphered backs running on bare registers.", "The 35.1/73.5 kN ratings assume the spherical contacts are free to find their seat — a painted-over or shimmed U washer fixes the angle and turns the self-aligning bearing into an edge-loaded one.", "Ordering discipline for 54207: the catalogue page quotes 54207 plus U 207 and its 35.1/73.5 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 54207?", "a": "54207 measures 30 mm bore × 62 mm OD × 37.8 mm bearing height (1.181 × 2.441 × 1.488 in), or 42 mm mounted H1 including the U 207 seat washer, mass about 530 g. SKF 17000 ratings: C 35.1 kN, C0 73.5 kN, Pu 2.7 kN, reference speed 2,800 r/min (thermal) and limiting speed 4,000 r/min (mechanical)." }, { "q": "What does the designation 54207 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 30 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 4 = double direction with sphered seating surfaces." }, { "q": "Does the spherical seat work while the shaft rocks continuously?", "a": "No — it accommodates initial static misalignment only. Continuous oscillation frets the sphered contacts even with C0 73.5 kN in reserve; keep the interfaces greased and clean and design genuine pivots separately." }, { "q": "What loads can 54207 take?", "a": "Pure axial load in both directions: C 35.1 kN, C0 73.5 kN, Pu 2.7 kN, with the same minimum-load rule (factor A 0.028) in each direction; radial load is excluded." } ], "cross_ref": [ { "equiv_sku": "54207", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "54207", "54207 + U 207" ], "locale_variants": {} }, { "sku": "54208", "brand": "SKF", "manufacturer_designation": "54208", "series": "54200-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 68, "B_mm": 38.6, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 44.2, "static_load_kN": 96.5, "fatigue_load_limit_kN": 3.6, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 630, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 54208 is an ISO 104 double-direction thrust ball bearing, 30 mm bore and 68 mm OD, with a sphered housing washer and U seat washer, standing 38.6 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 54208 is 30 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 30×68×38.6 mm (1.181×2.677×1.52 in), 19.0 mm radial section, C 44.2 kN, C0 96.5 kN, Pu 3.6 kN. Mounted height H1 44 mm includes the U 208 seat washer; the bearing alone is 38.6 mm high. reference speed 2,800 r/min (thermal) and limiting speed 3,800 r/min (mechanical), catalogue mass 630 g. At the printed limiting speed of 3,800 r/min the mean pitch diameter dm ≈ 49.0 mm implies a dn value around 186k mm·r/min; the 2,800 r/min reference speed is the thermal-planning value under catalogue load. Imperial cross-check for procurement drawings: 1.181 in bore, 2.677 in OD, 1.52 in height, and the 630 g catalogue mass converts to 0.630 kg (22.2 oz). Track-circle loading: per millimetre of mean track circumference the 44.2 kN dynamic rating corresponds to roughly 0.29 kN/mm of π·dm track, a useful comparison against the other dimension series of the 30 mm bore. Minimum-load arithmetic: with dm ≈ 49.0 mm and factor A 0.058, Fam ≈ A·(n·dm/1000)² at the 2,800 r/min reference speed is about 1.1 kN for 54208; below that preload the balls skid and smear the tracks. Speed planning separates the two ceilings mechanically: the pressed cage and balls tolerate 3,800 r/min while thermal balance under catalogue load sets the 2,800 r/min reference; at dm ≈ 49.0 mm the corresponding dn is approximately 186k mm·r/min. Bidirectional self-aligning note: TWO U seat washers are required for this order number, one behind each housing washer, and the catalogue H1 height includes them on both sides of the stack; the spherical interfaces accept initial misalignment in either load direction but are not pivots for continuous oscillation. Bill of materials for this page is 54208 plus TWO × U 208; the 44 mm H1 stack sits in a housing whose two register faces should be machined in one clamping to keep both spherical axes coincident.", "applications": [ "bidirectional crane-hook and swivel positions with deflecting structure", "reversing vertical pumps on fabricated bases", "agricultural reversing linkage pivots" ], "failure_modes": [ "cover-induced thrust preload when the end cover is torqued solid instead of leaving the catalogue axial freedom", "brinelling of one track pair from a static reversing shock concentrated on a single side", "edge loading on the ball set when the U seat washer is fitted with its concave face reversed", "one-side spherical seizure after grit fills the interface of the U washer on the less-loaded side", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Assembly is a five-component stack (central shaft washer, two cage sets, two sphered housing washers) plus the two U seat washers in the housing registers; dry-build the arrangement by hand first to confirm both sides swivel freely.", "The 44.2/96.5 kN ratings assume the spherical contacts are free to find their seat — a painted-over or shimmed U washer fixes the angle and turns the self-aligning bearing into an edge-loaded one.", "Minimum load factor A 0.058 applies to both load directions, and both brass pressed cage sets need lubricant reaching the upper track on a vertical shaft.", "Order TWO seat washers for 54208 — the designation U 208 pairs with one side and a second U washer (same number) with the other; the catalogue 44 mm H1 includes both.", "Ordering discipline for 54208: the catalogue page quotes 54208 plus U 208 and its 44.2/96.5 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 54208?", "a": "The catalogue envelope is 30×68×38.6 mm plus the 5.4 mm the U 208 seat washer adds to reach H1 44 mm, mass 630 g; ratings C 44.2 kN / C0 96.5 kN / Pu 3.6 kN, reference speed 2,800 r/min (thermal) and limiting speed 3,800 r/min (mechanical)." }, { "q": "What does the designation 54208 mean?", "a": "note the bore of 54208 is 30 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 4 = double direction with sphered seating surfaces." }, { "q": "How are the two U washers ordered and fitted?", "a": "Order two pieces of U 208 and seat one flat-backed in each housing register with the concave faces towards the sphered housing washers; check both interfaces swivel freely before fitting the central shaft washer, and verify the mounted stack measures the 44 mm H1." }, { "q": "How many U seat washers does 54208 need?", "a": "Two — one behind each sphered housing washer (the designation U 208 applies to each). The 44 mm H1 installed height includes both, while the bearing itself is 38.6 mm high." } ], "cross_ref": [ { "equiv_sku": "54208", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "54208", "54208 + U 208" ], "locale_variants": {} }, { "sku": "54307", "brand": "SKF", "manufacturer_designation": "54307", "series": "54300-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 68, "B_mm": 47.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 49.4, "static_load_kN": 96.5, "fatigue_load_limit_kN": 3.55, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "54307 is SKF's 30 mm-bore double-direction thrust ball bearing in the 54300 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 30×68×47.2 mm U 307 seat washer companion included in the mounted H1 dimension. The unit stacks one central shaft washer (ground bore, tight on the shaft), two outward-facing housing washers and two ball-cage assemblies, reacting axial force in both directions. double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 30 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 30×68×47.2 mm (1.181×2.677×1.858 in), 19.0 mm radial section, C 49.4 kN, C0 96.5 kN, Pu 3.55 kN. Mounted height H1 52 mm includes the U 307 seat washer; the bearing alone is 47.2 mm high. reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical), catalogue mass 850 g. Imperial cross-check for procurement drawings: 1.181 in bore, 2.677 in OD, 1.858 in height, and the 850 g catalogue mass converts to 0.850 kg (30.0 oz). Washer-stack proportions: the U 307 seat washer adds 4.8 mm to the 47.2 mm bearing height for a mounted H1 of 52 mm, while the 19.0 mm radial section against 30 mm bore (section/bore ≈ 0.63) identifies the envelope. Bore-to-OD planning: OD 68 over bore 30 is a 2.27× step for this size, and the 47.2 mm height gives a bore/height ratio of 0.64; use these ratios when the housing recess around the 30 mm shaft is the first constraint. Capacity density: 49.4 kN C from 0.850 kg of bearing steel gives about 58.1 kN per kilogram; static density is correspondingly 113.5 kN/kg at C0 96.5 kN. Speed band width for this size is 1,000 r/min between reference and limiting (1.42× ratio); lubrication, preload and heat removal decide where inside that band 54307 can actually run. Bidirectional self-aligning note: TWO U seat washers are required for this order number, one behind each housing washer, and the catalogue H1 height includes them on both sides of the stack; the spherical interfaces accept initial misalignment in either load direction but are not pivots for continuous oscillation. Bill of materials for this page is 54307 plus TWO × U 307; the 52 mm H1 stack sits in a housing whose two register faces should be machined in one clamping to keep both spherical axes coincident.", "applications": [ "medium screw jacks loaded in both directions", "bidirectional crane-hook and swivel positions with deflecting structure", "machine-tool reversing supports on elastic housings" ], "failure_modes": [ "track-edge spalling after the shaft washer seat is machined out of square and both rows share the tilt", "ball skidding on the momentarily unloaded side during rapid thrust reversal below the minimum load", "corrosion lock of the spherical pair during long outdoor idleness with no preservative grease", "one-side spherical seizure after grit fills the interface of the U washer on the less-loaded side", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "Order TWO seat washers for 54307 — the designation U 307 pairs with one side and a second U washer (same number) with the other; the catalogue 52 mm H1 includes both.", "The two spherical interfaces accommodate initial misalignment in either load direction but must stay clean, greased and static — continuous rocking frets the sphered contacts of even the 96.5 kN static-rated set.", "Assembly is a five-component stack (central shaft washer, two cage sets, two sphered housing washers) plus the two U seat washers in the housing registers; dry-build the arrangement by hand first to confirm both sides swivel freely.", "Minimum load factor A 0.048 applies to both load directions, and both brass pressed cage sets need lubricant reaching the upper track on a vertical shaft.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 54307 as the double sphered pressed steel execution; other order numbers of the 54307 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 307 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 54307?", "a": "54307 measures 30 mm bore × 68 mm OD × 47.2 mm bearing height (1.181 × 2.677 × 1.858 in), or 52 mm mounted H1 including the U 307 seat washer, mass about 850 g. SKF 17000 ratings: C 49.4 kN, C0 96.5 kN, Pu 3.55 kN, reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical)." }, { "q": "What does the designation 54307 mean?", "a": "double-direction 52/54 numbering does NOT decode the bore by the usual single-direction ×5 code — read the 30 mm bore from the dimension table; codes recur across the 522/523/524 sections and systematically trail the 51/53 code values. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. 5 = thrust ball bearing, 4 = double direction with sphered seating surfaces." }, { "q": "What loads can 54307 take?", "a": "Pure axial load in both directions: C 49.4 kN, C0 96.5 kN, Pu 3.55 kN, with the same minimum-load rule (factor A 0.048) in each direction; radial load is excluded." }, { "q": "How are the two U washers ordered and fitted?", "a": "Order two pieces of U 307 and seat one flat-backed in each housing register with the concave faces towards the sphered housing washers; check both interfaces swivel freely before fitting the central shaft washer, and verify the mounted stack measures the 52 mm H1." } ], "cross_ref": [ { "equiv_sku": "54307", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "54307", "54307 + U 307" ], "locale_variants": {} }, { "sku": "54308", "brand": "SKF", "manufacturer_designation": "54308", "series": "54300-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 78, "B_mm": 54.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 61.8, "static_load_kN": 122, "fatigue_load_limit_kN": 4.5, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 54300 series order number 54308 is a SKF double-direction thrust ball bearing for a 30 mm seat, built to ISO 104, with a sphered housing washer paired to a U seat washer, 30×78×54.1 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 30 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 30×78×54.1 mm (1.181×3.071×2.13 in), 24.0 mm radial section, C 61.8 kN, C0 122 kN, Pu 4.5 kN. Mounted height H1 59 mm includes the U 308 seat washer; the bearing alone is 54.1 mm high. reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical), catalogue mass 1150 g. Speed band width for this size is 800 r/min between reference and limiting (1.36× ratio); lubrication, preload and heat removal decide where inside that band 54308 can actually run. Capacity density: 61.8 kN C from 1.150 kg of bearing steel gives about 53.7 kN per kilogram; static density is correspondingly 106.1 kN/kg at C0 122 kN. At the printed limiting speed of 3,000 r/min the mean pitch diameter dm ≈ 54.0 mm implies a dn value around 162k mm·r/min; the 2,200 r/min reference speed is the thermal-planning value under catalogue load. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.077 at the 3,000 r/min limiting speed raises the required axial preload to about 2.0 kN; the reference-speed value 1.1 kN is the thermal design point. Minimum-load arithmetic: with dm ≈ 54.0 mm and factor A 0.077, Fam ≈ A·(n·dm/1000)² at the 2,200 r/min reference speed is about 1.1 kN for 54308; below that preload the balls skid and smear the tracks. Bidirectional self-aligning note: TWO U seat washers are required for this order number, one behind each housing washer, and the catalogue H1 height includes them on both sides of the stack; the spherical interfaces accept initial misalignment in either load direction but are not pivots for continuous oscillation. Bill of materials for this page is 54308 plus TWO × U 308; the 59 mm H1 stack sits in a housing whose two register faces should be machined in one clamping to keep both spherical axes coincident.", "applications": [ "medium screw jacks loaded in both directions", "bidirectional crane-hook and swivel positions with deflecting structure", "agricultural reversing linkage pivots" ], "failure_modes": [ "thermal lock-up when differential expansion removes the end play of the tighter-loaded side", "track-edge spalling after the shaft washer seat is machined out of square and both rows share the tilt", "total loss of the aligning function after paint, scale or abrasive dust fills the sphered contact", "one-side spherical seizure after grit fills the interface of the U washer on the less-loaded side", "false brinelling of the stationary tracks while the machine stands under vibration", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The 61.8/122 kN ratings assume the spherical contacts are free to find their seat — a painted-over or shimmed U washer fixes the angle and turns the self-aligning bearing into an edge-loaded one.", "Replacement ordering is THREE numbers: 54308 plus two pieces of U 308; quoting only the bearing leaves the sphered backs running on bare registers.", "Assembly is a five-component stack (central shaft washer, two cage sets, two sphered housing washers) plus the two U seat washers in the housing registers; dry-build the arrangement by hand first to confirm both sides swivel freely.", "Order TWO seat washers for 54308 — the designation U 308 pairs with one side and a second U washer (same number) with the other; the catalogue 59 mm H1 includes both.", "Ordering discipline for 54308: the catalogue page quotes 54308 plus U 308 and its 61.8/122 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 54308?", "a": "Boundary dimensions to ISO 104: bore 30 mm, OD 78 mm, height 54.1 mm (H1 59 mm installed with the U 308 seat washer); weight 1150 g. Load figures from SKF 17000: dynamic 61.8 kN, static 122 kN, fatigue limit 4.5 kN; reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical)." }, { "q": "What does the designation 54308 mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 30 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 4 = double direction with sphered seating surfaces." }, { "q": "What loads can 54308 take?", "a": "Pure axial load in both directions: C 61.8 kN, C0 122 kN, Pu 4.5 kN, with the same minimum-load rule (factor A 0.077) in each direction; radial load is excluded." }, { "q": "How are the two U washers ordered and fitted?", "a": "Order two pieces of U 308 and seat one flat-backed in each housing register with the concave faces towards the sphered housing washers; check both interfaces swivel freely before fitting the central shaft washer, and verify the mounted stack measures the 59 mm H1." } ], "cross_ref": [ { "equiv_sku": "54308", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "54308", "54308 + U 308" ], "locale_variants": {} }, { "sku": "54209", "brand": "SKF", "manufacturer_designation": "54209", "series": "54200-series", "type": "thrust_ball", "d_mm": 35, "D_mm": 73, "B_mm": 39.6, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 39, "static_load_kN": 86.5, "fatigue_load_limit_kN": 3.2, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 780, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 54209 is an ISO 104 double-direction thrust ball bearing, 35 mm bore and 73 mm OD, with a sphered housing washer and U seat washer, standing 39.6 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 54209 is 35 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 35×73×39.6 mm (1.378×2.874×1.559 in), 19.0 mm radial section, C 39 kN, C0 86.5 kN, Pu 3.2 kN. Mounted height H1 45 mm includes the U 209 seat washer; the bearing alone is 39.6 mm high. reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical), catalogue mass 780 g. Capacity density: 39 kN C from 0.780 kg of bearing steel gives about 50.0 kN per kilogram; static density is correspondingly 110.9 kN/kg at C0 86.5 kN. Mass and section check: 780 g inside the 35×73×39.6 mm outline leaves a 19.0 mm radial section, and the 86.5 kN static rating is 2.22× the dynamic rating — plan static safety and minimum preload against those figures. Track-circle loading: per millimetre of mean track circumference the 39 kN dynamic rating corresponds to roughly 0.23 kN/mm of π·dm track, a useful comparison against the other dimension series of the 35 mm bore. Rating split for documentation: dynamic 39 kN (L10 life), static 86.5 kN (safety factor s0), fatigue limit 3.2 kN (adjusted life) — three different uses of three different numbers for 54209, none interchangeable with another. Minimum-load arithmetic: with dm ≈ 54.0 mm and factor A 0.038, Fam ≈ A·(n·dm/1000)² at the 2,600 r/min reference speed is about 749 N for 54209; below that preload the balls skid and smear the tracks. Bidirectional self-aligning note: TWO U seat washers are required for this order number, one behind each housing washer, and the catalogue H1 height includes them on both sides of the stack; the spherical interfaces accept initial misalignment in either load direction but are not pivots for continuous oscillation. Bill of materials for this page is 54209 plus TWO × U 209; the 45 mm H1 stack sits in a housing whose two register faces should be machined in one clamping to keep both spherical axes coincident.", "applications": [ "reversing vertical pumps on fabricated bases", "bidirectional crane-hook and swivel positions with deflecting structure", "medium screw jacks loaded in both directions" ], "failure_modes": [ "ball skidding on the momentarily unloaded side during rapid thrust reversal below the minimum load", "brinelling of one track pair from a static reversing shock concentrated on a single side", "point-contact destruction of the housing register when a sphered washer is operated directly on a flat face without its U seat washer", "one-side spherical seizure after grit fills the interface of the U washer on the less-loaded side", "overheating from grease overfill churning inside a sealed housing recess with no escape volume", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "The two spherical interfaces accommodate initial misalignment in either load direction but must stay clean, greased and static — continuous rocking frets the sphered contacts of even the 86.5 kN static-rated set.", "Assembly is a five-component stack (central shaft washer, two cage sets, two sphered housing washers) plus the two U seat washers in the housing registers; dry-build the arrangement by hand first to confirm both sides swivel freely.", "Order TWO seat washers for 54209 — the designation U 209 pairs with one side and a second U washer (same number) with the other; the catalogue 45 mm H1 includes both.", "Minimum load factor A 0.038 applies to both load directions, and both brass pressed cage sets need lubricant reaching the upper track on a vertical shaft.", "The 39/86.5 kN figures belong to 54209 specifically (the double sphered pressed steel execution of 54209); suffixed, sphered and counterpart-series order numbers are separate articles, and U 209 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 54209?", "a": "The catalogue envelope is 35×73×39.6 mm plus the 5.4 mm the U 209 seat washer adds to reach H1 45 mm, mass 780 g; ratings C 39 kN / C0 86.5 kN / Pu 3.2 kN, reference speed 2,600 r/min (thermal) and limiting speed 3,600 r/min (mechanical)." }, { "q": "What does the designation 54209 mean?", "a": "note the bore of 54209 is 35 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 4 = double direction with sphered seating surfaces." }, { "q": "How are the two U washers ordered and fitted?", "a": "Order two pieces of U 209 and seat one flat-backed in each housing register with the concave faces towards the sphered housing washers; check both interfaces swivel freely before fitting the central shaft washer, and verify the mounted stack measures the 45 mm H1." }, { "q": "How many U seat washers does 54209 need?", "a": "Two — one behind each sphered housing washer (the designation U 209 applies to each). The 45 mm H1 installed height includes both, while the bearing itself is 39.6 mm high." } ], "cross_ref": [ { "equiv_sku": "54209", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "54209", "54209 + U 209" ], "locale_variants": {} }, { "sku": "54309", "brand": "SKF", "manufacturer_designation": "54309", "series": "54300-series", "type": "thrust_ball", "d_mm": 35, "D_mm": 85, "B_mm": 56.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 76.1, "static_load_kN": 153, "fatigue_load_limit_kN": 5.6, "reference_speed_rpm": 1900, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 1600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 54309 is an ISO 104 double-direction thrust ball bearing, 35 mm bore and 85 mm OD, with a sphered housing washer and U seat washer, standing 56.2 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 54309 is 35 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 35×85×56.2 mm (1.378×3.346×2.213 in), 25.0 mm radial section, C 76.1 kN, C0 153 kN, Pu 5.6 kN. Mounted height H1 62 mm includes the U 309 seat washer; the bearing alone is 56.2 mm high. reference speed 1,900 r/min (thermal) and limiting speed 2,800 r/min (mechanical), catalogue mass 1600 g. Load balance: C0 153 kN against C 76.1 kN gives a 2.01 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 5.6 kN enters the adjusted-life check. Bore-to-OD planning: OD 85 over bore 35 is a 2.43× step for this size, and the 56.2 mm height gives a bore/height ratio of 0.62; use these ratios when the housing recess around the 35 mm shaft is the first constraint. Mass and section check: 1600 g inside the 35×85×56.2 mm outline leaves a 25.0 mm radial section, and the 153 kN static rating is 2.01× the dynamic rating — plan static safety and minimum preload against those figures. Light-load floor: Pu = 5.6 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 54309; the number is 7 % of the 76.1 kN dynamic rating. Imperial cross-check for procurement drawings: 1.378 in bore, 3.346 in OD, 2.213 in height, and the 1600 g catalogue mass converts to 1.600 kg (56.4 oz). Bidirectional self-aligning note: TWO U seat washers are required for this order number, one behind each housing washer, and the catalogue H1 height includes them on both sides of the stack; the spherical interfaces accept initial misalignment in either load direction but are not pivots for continuous oscillation. At 35×85×56.2 mm the bearing carries C0 153 kN bidirectionally, but the two U interfaces share that load only if each is free to seat; torque the covers so the 5.8 mm-per-side washer steps are not pre-clamped.", "applications": [ "agricultural reversing linkage pivots", "machine-tool reversing supports on elastic housings", "medium screw jacks loaded in both directions" ], "failure_modes": [ "differential wear when one cage set loses lubrication first on a vertical mounting", "track-edge spalling after the shaft washer seat is machined out of square and both rows share the tilt", "total loss of the aligning function after paint, scale or abrasive dust fills the sphered contact", "one-side spherical seizure after grit fills the interface of the U washer on the less-loaded side", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The two spherical interfaces accommodate initial misalignment in either load direction but must stay clean, greased and static — continuous rocking frets the sphered contacts of even the 153 kN static-rated set.", "Replacement ordering is THREE numbers: 54309 plus two pieces of U 309; quoting only the bearing leaves the sphered backs running on bare registers.", "Minimum load factor A 0.12 applies to both load directions, and both brass pressed cage sets need lubricant reaching the upper track on a vertical shaft.", "Assembly is a five-component stack (central shaft washer, two cage sets, two sphered housing washers) plus the two U seat washers in the housing registers; dry-build the arrangement by hand first to confirm both sides swivel freely.", "The 76.1/153 kN figures belong to 54309 specifically (the double sphered pressed steel execution of 54309); suffixed, sphered and counterpart-series order numbers are separate articles, and U 309 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 54309?", "a": "The catalogue envelope is 35×85×56.2 mm plus the 5.8 mm the U 309 seat washer adds to reach H1 62 mm, mass 1600 g; ratings C 76.1 kN / C0 153 kN / Pu 5.6 kN, reference speed 1,900 r/min (thermal) and limiting speed 2,800 r/min (mechanical)." }, { "q": "What does the designation 54309 mean?", "a": "note the bore of 54309 is 35 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 4 = double direction with sphered seating surfaces." }, { "q": "How many U seat washers does 54309 need?", "a": "Two — one behind each sphered housing washer (the designation U 309 applies to each). The 62 mm H1 installed height includes both, while the bearing itself is 56.2 mm high." }, { "q": "What is the difference between 54309 and two single-direction 53-series bearings?", "a": "54309 is one factory-matched bidirectional unit with a central shaft washer; two 53-series bearings would need two shaft seats and roughly twice the axial space with separate fits. The 54-series is the compact reversing counterpart, not a stacking kit." } ], "cross_ref": [ { "equiv_sku": "54309", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "54309", "54309 + U 309" ], "locale_variants": {} }, { "sku": "54409", "brand": "SKF", "manufacturer_designation": "54409", "series": "54400-series", "type": "thrust_ball", "d_mm": 35, "D_mm": 100, "B_mm": 78.9, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 124, "static_load_kN": 240, "fatigue_load_limit_kN": 9, "reference_speed_rpm": 1500, "limiting_speed_rpm": 2000, "max_rpm": 2000, "weight_g": 3000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 54409 is an ISO 104 double-direction thrust ball bearing, 35 mm bore and 100 mm OD, with a sphered housing washer and U seat washer, standing 78.9 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 54409 is 35 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 35×100×78.9 mm (1.378×3.937×3.106 in), 32.5 mm radial section, C 124 kN, C0 240 kN, Pu 9 kN. Mounted height H1 86 mm includes the U 409 seat washer; the bearing alone is 78.9 mm high. reference speed 1,500 r/min (thermal) and limiting speed 2,000 r/min (mechanical), catalogue mass 3000 g. At the printed limiting speed of 2,000 r/min the mean pitch diameter dm ≈ 67.5 mm implies a dn value around 135k mm·r/min; the 1,500 r/min reference speed is the thermal-planning value under catalogue load. Pitch-diameter arithmetic: dm = (35+100)/2 = 67.5 mm; at the 2,000 r/min limiting speed that corresponds to roughly 135k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.37 at the 2,000 r/min limiting speed raises the required axial preload to about 6.7 kN; the reference-speed value 3.8 kN is the thermal design point. Mass and section check: 3000 g inside the 35×100×78.9 mm outline leaves a 32.5 mm radial section, and the 240 kN static rating is 1.94× the dynamic rating — plan static safety and minimum preload against those figures. Bore-to-OD planning: OD 100 over bore 35 is a 2.86× step for this size, and the 78.9 mm height gives a bore/height ratio of 0.44; use these ratios when the housing recess around the 35 mm shaft is the first constraint. Bidirectional self-aligning note: TWO U seat washers are required for this order number, one behind each housing washer, and the catalogue H1 height includes them on both sides of the stack; the spherical interfaces accept initial misalignment in either load direction but are not pivots for continuous oscillation. At 35×100×78.9 mm the bearing carries C0 240 kN bidirectionally, but the two U interfaces share that load only if each is free to seat; torque the covers so the 7.1 mm-per-side washer steps are not pre-clamped.", "applications": [ "reversing vertical pumps on fabricated bases", "agricultural reversing linkage pivots", "medium screw jacks loaded in both directions" ], "failure_modes": [ "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "brinelling of one track pair from a static reversing shock concentrated on a single side", "fretting corrosion in the spherical interface under oscillation with no grease between washer and seat", "one-side spherical seizure after grit fills the interface of the U washer on the less-loaded side", "washer face scoring from swarf trapped between the loose housing washer and its register", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "Order TWO seat washers for 54409 — the designation U 409 pairs with one side and a second U washer (same number) with the other; the catalogue 86 mm H1 includes both.", "Minimum load factor A 0.37 applies to both load directions, and both brass pressed cage sets need lubricant reaching the upper track on a vertical shaft.", "Assembly is a five-component stack (central shaft washer, two cage sets, two sphered housing washers) plus the two U seat washers in the housing registers; dry-build the arrangement by hand first to confirm both sides swivel freely.", "The two spherical interfaces accommodate initial misalignment in either load direction but must stay clean, greased and static — continuous rocking frets the sphered contacts of even the 240 kN static-rated set.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 54409 as the double sphered pressed steel execution; other order numbers of the 54409 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 409 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 54409?", "a": "The catalogue envelope is 35×100×78.9 mm plus the 7.1 mm the U 409 seat washer adds to reach H1 86 mm, mass 3000 g; ratings C 124 kN / C0 240 kN / Pu 9 kN, reference speed 1,500 r/min (thermal) and limiting speed 2,000 r/min (mechanical)." }, { "q": "What does the designation 54409 mean?", "a": "note the bore of 54409 is 35 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 4 = double direction with sphered seating surfaces." }, { "q": "Does the spherical seat work while the shaft rocks continuously?", "a": "No — it accommodates initial static misalignment only. Continuous oscillation frets the sphered contacts even with C0 240 kN in reserve; keep the interfaces greased and clean and design genuine pivots separately." }, { "q": "What loads can 54409 take?", "a": "Pure axial load in both directions: C 124 kN, C0 240 kN, Pu 9 kN, with the same minimum-load rule (factor A 0.37) in each direction; radial load is excluded." } ], "cross_ref": [ { "equiv_sku": "54409", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "54409", "54409 + U 409" ], "locale_variants": {} }, { "sku": "54310", "brand": "SKF", "manufacturer_designation": "54310", "series": "54300-series", "type": "thrust_ball", "d_mm": 40, "D_mm": 95, "B_mm": 64.7, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 81.9, "static_load_kN": 170, "fatigue_load_limit_kN": 6.3, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 2300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 54310 is an ISO 104 double-direction thrust ball bearing, 40 mm bore and 95 mm OD, with a sphered housing washer and U seat washer, standing 64.7 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 54310 is 40 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 40×95×64.7 mm (1.575×3.74×2.547 in), 27.5 mm radial section, C 81.9 kN, C0 170 kN, Pu 6.3 kN. Mounted height H1 70 mm includes the U 310 seat washer; the bearing alone is 64.7 mm high. reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical), catalogue mass 2300 g. Light-load floor: Pu = 6.3 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 54310; the number is 8 % of the 81.9 kN dynamic rating. At the printed limiting speed of 2,400 r/min the mean pitch diameter dm ≈ 67.5 mm implies a dn value around 162k mm·r/min; the 1,700 r/min reference speed is the thermal-planning value under catalogue load. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.19 at the 2,400 r/min limiting speed raises the required axial preload to about 5.0 kN; the reference-speed value 2.5 kN is the thermal design point. Pitch-diameter arithmetic: dm = (40+95)/2 = 67.5 mm; at the 2,400 r/min limiting speed that corresponds to roughly 162k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Static-first selection data: 170 kN C0 spread across the 64.7 mm stack gives 2.6 kN of static rating per height millimetre, and the 2300 g mass/C0 ratio is about 14 g per static kN — crane-hook and screw positions are normally sized on these two figures. Bidirectional self-aligning note: TWO U seat washers are required for this order number, one behind each housing washer, and the catalogue H1 height includes them on both sides of the stack; the spherical interfaces accept initial misalignment in either load direction but are not pivots for continuous oscillation. At 40×95×64.7 mm the bearing carries C0 170 kN bidirectionally, but the two U interfaces share that load only if each is free to seat; torque the covers so the 5.3 mm-per-side washer steps are not pre-clamped.", "applications": [ "reversing vertical pumps on fabricated bases", "medium screw jacks loaded in both directions", "bidirectional crane-hook and swivel positions with deflecting structure" ], "failure_modes": [ "thermal lock-up when differential expansion removes the end play of the tighter-loaded side", "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "point-contact destruction of the housing register when a sphered washer is operated directly on a flat face without its U seat washer", "one-side spherical seizure after grit fills the interface of the U washer on the less-loaded side", "abrasive scoring of washers and balls when the open arrangement runs without external sealing", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit" ], "pitfalls": [ "The 81.9/170 kN ratings assume the spherical contacts are free to find their seat — a painted-over or shimmed U washer fixes the angle and turns the self-aligning bearing into an edge-loaded one.", "Assembly is a five-component stack (central shaft washer, two cage sets, two sphered housing washers) plus the two U seat washers in the housing registers; dry-build the arrangement by hand first to confirm both sides swivel freely.", "Minimum load factor A 0.19 applies to both load directions, and both brass pressed cage sets need lubricant reaching the upper track on a vertical shaft.", "Order TWO seat washers for 54310 — the designation U 310 pairs with one side and a second U washer (same number) with the other; the catalogue 70 mm H1 includes both.", "Ordering discipline for 54310: the catalogue page quotes 54310 plus U 310 and its 81.9/170 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 54310?", "a": "The catalogue envelope is 40×95×64.7 mm plus the 5.3 mm the U 310 seat washer adds to reach H1 70 mm, mass 2300 g; ratings C 81.9 kN / C0 170 kN / Pu 6.3 kN, reference speed 1,700 r/min (thermal) and limiting speed 2,400 r/min (mechanical)." }, { "q": "What does the designation 54310 mean?", "a": "note the bore of 54310 is 40 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 4 = double direction with sphered seating surfaces." }, { "q": "What is the difference between 54310 and two single-direction 53-series bearings?", "a": "54310 is one factory-matched bidirectional unit with a central shaft washer; two 53-series bearings would need two shaft seats and roughly twice the axial space with separate fits. The 54-series is the compact reversing counterpart, not a stacking kit." }, { "q": "Does the spherical seat work while the shaft rocks continuously?", "a": "No — it accommodates initial static misalignment only. Continuous oscillation frets the sphered contacts even with C0 170 kN in reserve; keep the interfaces greased and clean and design genuine pivots separately." } ], "cross_ref": [ { "equiv_sku": "54310", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "54310", "54310 + U 310" ], "locale_variants": {} }, { "sku": "54410", "brand": "SKF", "manufacturer_designation": "54410", "series": "54400-series", "type": "thrust_ball", "d_mm": 40, "D_mm": 110, "B_mm": 83.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 148, "static_load_kN": 305, "fatigue_load_limit_kN": 11.4, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1900, "max_rpm": 1900, "weight_g": 4450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 54400 series order number 54410 is a SKF double-direction thrust ball bearing for a 40 mm seat, built to ISO 104, with a sphered housing washer paired to a U seat washer, 40×110×83.2 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 40 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 40×110×83.2 mm (1.575×4.331×3.276 in), 35.0 mm radial section, C 148 kN, C0 305 kN, Pu 11.4 kN. Mounted height H1 92 mm includes the U 410 seat washer; the bearing alone is 83.2 mm high. reference speed 1,400 r/min (thermal) and limiting speed 1,900 r/min (mechanical), catalogue mass 4450 g. Speed-ratio note for this exact unit: the reference speed is 1,400 r/min against a 1,900 r/min limiting speed, a reference-to-limit ratio of 0.74. Minimum-load arithmetic: with dm ≈ 75.0 mm and factor A 0.6, Fam ≈ A·(n·dm/1000)² at the 1,400 r/min reference speed is about 6.6 kN for 54410; below that preload the balls skid and smear the tracks. Mass and section check: 4450 g inside the 40×110×83.2 mm outline leaves a 35.0 mm radial section, and the 305 kN static rating is 2.06× the dynamic rating — plan static safety and minimum preload against those figures. Rating split for documentation: dynamic 148 kN (L10 life), static 305 kN (safety factor s0), fatigue limit 11.4 kN (adjusted life) — three different uses of three different numbers for 54410, none interchangeable with another. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.6 at the 1,900 r/min limiting speed raises the required axial preload to about 12.2 kN; the reference-speed value 6.6 kN is the thermal design point. Bidirectional self-aligning note: TWO U seat washers are required for this order number, one behind each housing washer, and the catalogue H1 height includes them on both sides of the stack; the spherical interfaces accept initial misalignment in either load direction but are not pivots for continuous oscillation. At 40×110×83.2 mm the bearing carries C0 305 kN bidirectionally, but the two U interfaces share that load only if each is free to seat; torque the covers so the 8.8 mm-per-side washer steps are not pre-clamped.", "applications": [ "agricultural reversing linkage pivots", "reversing vertical pumps on fabricated bases", "medium screw jacks loaded in both directions" ], "failure_modes": [ "track-edge spalling after the shaft washer seat is machined out of square and both rows share the tilt", "assembly damage when the central shaft washer is fitted reversed or the two outward-facing housing washers are swapped", "edge loading on the ball set when the U seat washer is fitted with its concave face reversed", "one-side spherical seizure after grit fills the interface of the U washer on the less-loaded side", "washer face scoring from swarf trapped between the loose housing washer and its register", "grease starvation on a vertical shaft as lubricant drains away from the upper washer" ], "pitfalls": [ "Order TWO seat washers for 54410 — the designation U 410 pairs with one side and a second U washer (same number) with the other; the catalogue 92 mm H1 includes both.", "The 148/305 kN ratings assume the spherical contacts are free to find their seat — a painted-over or shimmed U washer fixes the angle and turns the self-aligning bearing into an edge-loaded one.", "Assembly is a five-component stack (central shaft washer, two cage sets, two sphered housing washers) plus the two U seat washers in the housing registers; dry-build the arrangement by hand first to confirm both sides swivel freely.", "Replacement ordering is THREE numbers: 54410 plus two pieces of U 410; quoting only the bearing leaves the sphered backs running on bare registers.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 54410 as the double sphered pressed steel execution; other order numbers of the 54410 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 410 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 54410?", "a": "Boundary dimensions to ISO 104: bore 40 mm, OD 110 mm, height 83.2 mm (H1 92 mm installed with the U 410 seat washer); weight 4450 g. Load figures from SKF 17000: dynamic 148 kN, static 305 kN, fatigue limit 11.4 kN; reference speed 1,400 r/min (thermal) and limiting speed 1,900 r/min (mechanical)." }, { "q": "What does the designation 54410 mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 40 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 4 = double direction with sphered seating surfaces." }, { "q": "Does the spherical seat work while the shaft rocks continuously?", "a": "No — it accommodates initial static misalignment only. Continuous oscillation frets the sphered contacts even with C0 305 kN in reserve; keep the interfaces greased and clean and design genuine pivots separately." }, { "q": "What loads can 54410 take?", "a": "Pure axial load in both directions: C 148 kN, C0 305 kN, Pu 11.4 kN, with the same minimum-load rule (factor A 0.6) in each direction; radial load is excluded." } ], "cross_ref": [ { "equiv_sku": "54410", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "54410", "54410 + U 410" ], "locale_variants": {} }, { "sku": "54211", "brand": "SKF", "manufacturer_designation": "54211", "series": "54200-series", "type": "thrust_ball", "d_mm": 45, "D_mm": 90, "B_mm": 49.6, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 58.5, "static_load_kN": 134, "fatigue_load_limit_kN": 4.9, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 54211 is an ISO 104 double-direction thrust ball bearing, 45 mm bore and 90 mm OD, with a sphered housing washer and U seat washer, standing 49.6 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 54211 is 45 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 45×90×49.6 mm (1.772×3.543×1.953 in), 22.5 mm radial section, C 58.5 kN, C0 134 kN, Pu 4.9 kN. Mounted height H1 55 mm includes the U 211 seat washer; the bearing alone is 49.6 mm high. reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical), catalogue mass 1300 g. Imperial cross-check for procurement drawings: 1.772 in bore, 3.543 in OD, 1.953 in height, and the 1300 g catalogue mass converts to 1.300 kg (45.9 oz). Washer-stack proportions: the U 211 seat washer adds 5.4 mm to the 49.6 mm bearing height for a mounted H1 of 55 mm, while the 22.5 mm radial section against 45 mm bore (section/bore ≈ 0.50) identifies the envelope. Pitch-diameter arithmetic: dm = (45+90)/2 = 67.5 mm; at the 3,000 r/min limiting speed that corresponds to roughly 203k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Rating split for documentation: dynamic 58.5 kN (L10 life), static 134 kN (safety factor s0), fatigue limit 4.9 kN (adjusted life) — three different uses of three different numbers for 54211, none interchangeable with another. Selection figures for 54211: the C0/C ratio is 2.29, Pu 4.9 kN is about 8 % of C, and the catalogue mass works out to roughly 29 g per millimetre of bore; the printed minimum-load factor is A 0.11. Bidirectional self-aligning note: TWO U seat washers are required for this order number, one behind each housing washer, and the catalogue H1 height includes them on both sides of the stack; the spherical interfaces accept initial misalignment in either load direction but are not pivots for continuous oscillation. Bill of materials for this page is 54211 plus TWO × U 211; the 55 mm H1 stack sits in a housing whose two register faces should be machined in one clamping to keep both spherical axes coincident.", "applications": [ "machine-tool reversing supports on elastic housings", "agricultural reversing linkage pivots", "reversing vertical pumps on fabricated bases" ], "failure_modes": [ "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "cage-set loss during handling because the five components separate as soon as the unit leaves the recess", "corrosion lock of the spherical pair during long outdoor idleness with no preservative grease", "one-side spherical seizure after grit fills the interface of the U washer on the less-loaded side", "fretting corrosion on the shaft-washer ground bore after a loose rotating fit", "overheating from grease overfill churning inside a sealed housing recess with no escape volume" ], "pitfalls": [ "Order TWO seat washers for 54211 — the designation U 211 pairs with one side and a second U washer (same number) with the other; the catalogue 55 mm H1 includes both.", "The two spherical interfaces accommodate initial misalignment in either load direction but must stay clean, greased and static — continuous rocking frets the sphered contacts of even the 134 kN static-rated set.", "Minimum load factor A 0.11 applies to both load directions, and both brass pressed cage sets need lubricant reaching the upper track on a vertical shaft.", "Assembly is a five-component stack (central shaft washer, two cage sets, two sphered housing washers) plus the two U seat washers in the housing registers; dry-build the arrangement by hand first to confirm both sides swivel freely.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 54211 as the double sphered pressed steel execution; other order numbers of the 54211 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 211 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 54211?", "a": "The catalogue envelope is 45×90×49.6 mm plus the 5.4 mm the U 211 seat washer adds to reach H1 55 mm, mass 1300 g; ratings C 58.5 kN / C0 134 kN / Pu 4.9 kN, reference speed 2,200 r/min (thermal) and limiting speed 3,000 r/min (mechanical)." }, { "q": "What does the designation 54211 mean?", "a": "note the bore of 54211 is 45 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 4 = double direction with sphered seating surfaces." }, { "q": "Does the spherical seat work while the shaft rocks continuously?", "a": "No — it accommodates initial static misalignment only. Continuous oscillation frets the sphered contacts even with C0 134 kN in reserve; keep the interfaces greased and clean and design genuine pivots separately." }, { "q": "What loads can 54211 take?", "a": "Pure axial load in both directions: C 58.5 kN, C0 134 kN, Pu 4.9 kN, with the same minimum-load rule (factor A 0.11) in each direction; radial load is excluded." } ], "cross_ref": [ { "equiv_sku": "54211", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "54211", "54211 + U 211" ], "locale_variants": {} }, { "sku": "54312", "brand": "SKF", "manufacturer_designation": "54312", "series": "54300-series", "type": "thrust_ball", "d_mm": 50, "D_mm": 110, "B_mm": 70.7, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 101, "static_load_kN": 224, "fatigue_load_limit_kN": 8.3, "reference_speed_rpm": 1500, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 2900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 54312 is an ISO 104 double-direction thrust ball bearing, 50 mm bore and 110 mm OD, with a sphered housing washer and U seat washer, standing 70.7 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 54312 is 50 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. Envelope 50×110×70.7 mm (1.969×4.331×2.783 in), 30.0 mm radial section, C 101 kN, C0 224 kN, Pu 8.3 kN. Mounted height H1 78 mm includes the U 312 seat washer; the bearing alone is 70.7 mm high. reference speed 1,500 r/min (thermal) and limiting speed 2,200 r/min (mechanical), catalogue mass 2900 g. Speed band width for this size is 700 r/min between reference and limiting (1.47× ratio); lubrication, preload and heat removal decide where inside that band 54312 can actually run. Speed-ratio note for this exact unit: the reference speed is 1,500 r/min against a 2,200 r/min limiting speed, a reference-to-limit ratio of 0.68. Load balance: C0 224 kN against C 101 kN gives a 2.22 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 8.3 kN enters the adjusted-life check. Light-load floor: Pu = 8.3 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 54312; the number is 8 % of the 101 kN dynamic rating. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.26 at the 2,200 r/min limiting speed raises the required axial preload to about 8.1 kN; the reference-speed value 3.7 kN is the thermal design point. Bidirectional self-aligning note: TWO U seat washers are required for this order number, one behind each housing washer, and the catalogue H1 height includes them on both sides of the stack; the spherical interfaces accept initial misalignment in either load direction but are not pivots for continuous oscillation. At 50×110×70.7 mm the bearing carries C0 224 kN bidirectionally, but the two U interfaces share that load only if each is free to seat; torque the covers so the 7.3 mm-per-side washer steps are not pre-clamped.", "applications": [ "bidirectional crane-hook and swivel positions with deflecting structure", "reversing vertical pumps on fabricated bases", "machine-tool reversing supports on elastic housings" ], "failure_modes": [ "differential wear when one cage set loses lubrication first on a vertical mounting", "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "tilted running after a mismatched U washer leaves only a narrow band of spherical contact", "one-side spherical seizure after grit fills the interface of the U washer on the less-loaded side", "grease starvation on a vertical shaft as lubricant drains away from the upper washer", "electrical discharge pitting when the shaft current passes through the ball contacts instead of a grounding brush" ], "pitfalls": [ "The two spherical interfaces accommodate initial misalignment in either load direction but must stay clean, greased and static — continuous rocking frets the sphered contacts of even the 224 kN static-rated set.", "Order TWO seat washers for 54312 — the designation U 312 pairs with one side and a second U washer (same number) with the other; the catalogue 78 mm H1 includes both.", "Minimum load factor A 0.26 applies to both load directions, and both brass pressed cage sets need lubricant reaching the upper track on a vertical shaft.", "Assembly is a five-component stack (central shaft washer, two cage sets, two sphered housing washers) plus the two U seat washers in the housing registers; dry-build the arrangement by hand first to confirm both sides swivel freely.", "The 101/224 kN figures belong to 54312 specifically (the double sphered pressed steel execution of 54312); suffixed, sphered and counterpart-series order numbers are separate articles, and U 312 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 54312?", "a": "The catalogue envelope is 50×110×70.7 mm plus the 7.3 mm the U 312 seat washer adds to reach H1 78 mm, mass 2900 g; ratings C 101 kN / C0 224 kN / Pu 8.3 kN, reference speed 1,500 r/min (thermal) and limiting speed 2,200 r/min (mechanical)." }, { "q": "What does the designation 54312 mean?", "a": "note the bore of 54312 is 50 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. no cage suffix means the standard stamped steel retainer — a pressed sheet-metal ball-cage assembly that covers the bulk of the thrust-ball assortment. 5 = thrust ball bearing, 4 = double direction with sphered seating surfaces." }, { "q": "How are the two U washers ordered and fitted?", "a": "Order two pieces of U 312 and seat one flat-backed in each housing register with the concave faces towards the sphered housing washers; check both interfaces swivel freely before fitting the central shaft washer, and verify the mounted stack measures the 78 mm H1." }, { "q": "How many U seat washers does 54312 need?", "a": "Two — one behind each sphered housing washer (the designation U 312 applies to each). The 78 mm H1 installed height includes both, while the bearing itself is 70.7 mm high." } ], "cross_ref": [ { "equiv_sku": "54312", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "54312", "54312 + U 312" ], "locale_variants": {} }, { "sku": "54316", "brand": "SKF", "manufacturer_designation": "54316", "series": "54300-series", "type": "thrust_ball", "d_mm": 65, "D_mm": 140, "B_mm": 86.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 159, "static_load_kN": 390, "fatigue_load_limit_kN": 13.7, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 5550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 54300 series order number 54316 is a SKF double-direction thrust ball bearing for a 65 mm seat, built to ISO 104, with a sphered housing washer paired to a U seat washer, 65×140×86.1 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 65 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 65×140×86.1 mm (2.559×5.512×3.39 in), 37.5 mm radial section, C 159 kN, C0 390 kN, Pu 13.7 kN. Mounted height H1 95 mm includes the U 316 seat washer; the bearing alone is 86.1 mm high. reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical), catalogue mass 5550 g. Track-circle loading: per millimetre of mean track circumference the 159 kN dynamic rating corresponds to roughly 0.49 kN/mm of π·dm track, a useful comparison against the other dimension series of the 65 mm bore. Speed-ratio note for this exact unit: the reference speed is 1,300 r/min against a 1,800 r/min limiting speed, a reference-to-limit ratio of 0.72. Static-first selection data: 390 kN C0 spread across the 86.1 mm stack gives 4.5 kN of static rating per height millimetre, and the 5550 g mass/C0 ratio is about 14 g per static kN — crane-hook and screw positions are normally sized on these two figures. Rating split for documentation: dynamic 159 kN (L10 life), static 390 kN (safety factor s0), fatigue limit 13.7 kN (adjusted life) — three different uses of three different numbers for 54316, none interchangeable with another. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.79 at the 1,800 r/min limiting speed raises the required axial preload to about 26.9 kN; the reference-speed value 14.0 kN is the thermal design point. Bidirectional self-aligning note: TWO U seat washers are required for this order number, one behind each housing washer, and the catalogue H1 height includes them on both sides of the stack; the spherical interfaces accept initial misalignment in either load direction but are not pivots for continuous oscillation. Bill of materials for this page is 54316 plus TWO × U 316; the 95 mm H1 stack sits in a housing whose two register faces should be machined in one clamping to keep both spherical axes coincident.", "applications": [ "large two-direction screwdown screws", "winch drives with bidirectional thrust on welded frames", "heavy turret and slewing adjustments" ], "failure_modes": [ "cover-induced thrust preload when the end cover is torqued solid instead of leaving the catalogue axial freedom", "assembly damage when the central shaft washer is fitted reversed or the two outward-facing housing washers are swapped", "fretting corrosion in the spherical interface under oscillation with no grease between washer and seat", "one-side spherical seizure after grit fills the interface of the U washer on the less-loaded side", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "washer face scoring from swarf trapped between the loose housing washer and its register" ], "pitfalls": [ "Assembly is a five-component stack (central shaft washer, two cage sets, two sphered housing washers) plus the two U seat washers in the housing registers; dry-build the arrangement by hand first to confirm both sides swivel freely.", "Minimum load factor A 0.79 applies to both load directions, and both brass pressed cage sets need lubricant reaching the upper track on a vertical shaft.", "The 159/390 kN ratings assume the spherical contacts are free to find their seat — a painted-over or shimmed U washer fixes the angle and turns the self-aligning bearing into an edge-loaded one.", "Replacement ordering is THREE numbers: 54316 plus two pieces of U 316; quoting only the bearing leaves the sphered backs running on bare registers.", "Ordering discipline for 54316: the catalogue page quotes 54316 plus U 316 and its 159/390 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 54316?", "a": "Boundary dimensions to ISO 104: bore 65 mm, OD 140 mm, height 86.1 mm (H1 95 mm installed with the U 316 seat washer); weight 5550 g. Load figures from SKF 17000: dynamic 159 kN, static 390 kN, fatigue limit 13.7 kN; reference speed 1,300 r/min (thermal) and limiting speed 1,800 r/min (mechanical)." }, { "q": "What does the designation 54316 mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 65 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 4 = double direction with sphered seating surfaces." }, { "q": "How many U seat washers does 54316 need?", "a": "Two — one behind each sphered housing washer (the designation U 316 applies to each). The 95 mm H1 installed height includes both, while the bearing itself is 86.1 mm high." }, { "q": "What is the difference between 54316 and two single-direction 53-series bearings?", "a": "54316 is one factory-matched bidirectional unit with a central shaft washer; two 53-series bearings would need two shaft seats and roughly twice the axial space with separate fits. The 54-series is the compact reversing counterpart, not a stacking kit." } ], "cross_ref": [ { "equiv_sku": "54316", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "54316", "54316 + U 316" ], "locale_variants": {} }, { "sku": "54416-M", "brand": "SKF", "manufacturer_designation": "54416 M", "series": "54400-series", "type": "thrust_ball", "d_mm": 65, "D_mm": 170, "B_mm": 128.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 307, "static_load_kN": 750, "fatigue_load_limit_kN": 25, "reference_speed_rpm": 850, "limiting_speed_rpm": 1200, "max_rpm": 1200, "weight_g": 17500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 54400 series order number 54416 M is a SKF double-direction thrust ball bearing for a 65 mm seat, built to ISO 104, with a sphered housing washer paired to a U seat washer, 65×170×128.5 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 65 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 65×170×128.5 mm (2.559×6.693×5.059 in), 52.5 mm radial section, C 307 kN, C0 750 kN, Pu 25 kN. Mounted height H1 140 mm includes the U 416 seat washer; the bearing alone is 128.5 mm high. reference speed 850 r/min (thermal) and limiting speed 1,200 r/min (mechanical), catalogue mass 17500 g. Sizing arithmetic on the 65 mm bore: 307 kN C over the 52.5 mm radial section gives 5.8 kN per section millimetre, and the 128.5 mm stack height is 2.45× that section — proportions typical of a 54400 thrust section. Speed-ratio note for this exact unit: the reference speed is 850 r/min against a 1,200 r/min limiting speed, a reference-to-limit ratio of 0.71. Capacity density: 307 kN C from 17.500 kg of bearing steel gives about 17.5 kN per kilogram; static density is correspondingly 42.9 kN/kg at C0 750 kN. Speed planning separates the two ceilings mechanically: the pressed brass cage and balls tolerate 1,200 r/min while thermal balance under catalogue load sets the 850 r/min reference; at dm ≈ 117.5 mm the corresponding dn is approximately 141k mm·r/min. Track-circle loading: per millimetre of mean track circumference the 307 kN dynamic rating corresponds to roughly 0.83 kN/mm of π·dm track, a useful comparison against the other dimension series of the 65 mm bore. Heavy bidirectional self-aligning note: the two machined brass cage sets and the two sphered housing washer / U seat-washer pairs make this the heaviest standard thrust-ball execution of its bore — check both spherical interfaces for fretting at overhaul and confirm both U washers are the catalogue-matched designations before reassembly. Condition monitoring of 54416 M should sample both sides independently: asymmetric wear between the two 750 kN-rated track pairs reveals unequal duty or one spherical interface that has stopped seating.", "applications": [ "large vertical-pump thrust with up-thrust events", "winch drives with bidirectional thrust on welded frames", "large two-direction screwdown screws" ], "failure_modes": [ "brinelling of one track pair from a static reversing shock concentrated on a single side", "cover-induced thrust preload when the end cover is torqued solid instead of leaving the catalogue axial freedom", "total loss of the aligning function after paint, scale or abrasive dust fills the sphered contact", "asymmetric cage wear when reversing duty loads one brass cage set far more often than the other", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "Minimum load factor A 2.3 applies to both load directions, and both brass machined cage sets need lubricant reaching the upper track on a vertical shaft.", "Replacement ordering is THREE numbers: 54416 M plus two pieces of U 416; quoting only the bearing leaves the sphered backs running on bare registers.", "The 307/750 kN ratings assume the spherical contacts are free to find their seat — a painted-over or shimmed U washer fixes the angle and turns the self-aligning bearing into an edge-loaded one.", "Order TWO seat washers for 54416 M — the designation U 416 pairs with one side and a second U washer (same number) with the other; the catalogue 140 mm H1 includes both.", "Catalogue ratings are SKF PUB BU/P1 17000 figures for 54416 M as the double sphered brass execution; other order numbers of the 54416 size are different products and may carry different ratings or seating geometry — always quote the full designation including the U 416 seat washer when purchasing." ], "faq": [ { "q": "What are the dimensions and catalogue data of 54416-M?", "a": "Boundary dimensions to ISO 104: bore 65 mm, OD 170 mm, height 128.5 mm (H1 140 mm installed with the U 416 seat washer); weight 17500 g. Load figures from SKF 17000: dynamic 307 kN, static 750 kN, fatigue limit 25 kN; reference speed 850 r/min (thermal) and limiting speed 1,200 r/min (mechanical)." }, { "q": "What does the designation 54416 M mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 65 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. 5 = thrust ball bearing, 4 = double direction with sphered seating surfaces." }, { "q": "How many U seat washers does 54416-M need?", "a": "Two — one behind each sphered housing washer (the designation U 416 applies to each). The 140 mm H1 installed height includes both, while the bearing itself is 128.5 mm high." }, { "q": "What is the difference between 54416 and two single-direction 53-series bearings?", "a": "54416 M is one factory-matched bidirectional unit with a central shaft washer; two 53-series bearings would need two shaft seats and roughly twice the axial space with separate fits. The 54-series is the compact reversing counterpart, not a stacking kit." } ], "cross_ref": [ { "equiv_sku": "54416", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "54416-M", "54416 M", "54416 M + U 416" ], "locale_variants": {} }, { "sku": "54317", "brand": "SKF", "manufacturer_designation": "54317", "series": "54300-series", "type": "thrust_ball", "d_mm": 70, "D_mm": 150, "B_mm": 95.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 174, "static_load_kN": 405, "fatigue_load_limit_kN": 14, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1500, "max_rpm": 1500, "weight_g": 7950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The 54300 series order number 54317 is a SKF double-direction thrust ball bearing for a 70 mm seat, built to ISO 104, with a sphered housing washer paired to a U seat washer, 70×150×95.2 mm boundary dimensions. Inside the unit sit a single central shaft washer with a ground interference bore, two outward-facing loose housing washers and two independent ball-cage assemblies, so axial force is reacted in both directions from one housing recess. bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 70 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 70×150×95.2 mm (2.756×5.906×3.748 in), 40.0 mm radial section, C 174 kN, C0 405 kN, Pu 14 kN. Mounted height H1 105 mm includes the U 317 seat washer; the bearing alone is 95.2 mm high. reference speed 1,100 r/min (thermal) and limiting speed 1,500 r/min (mechanical), catalogue mass 7950 g. Sizing arithmetic on the 70 mm bore: 174 kN C over the 40.0 mm radial section gives 4.3 kN per section millimetre, and the 95.2 mm stack height is 2.38× that section — proportions typical of a 54300 thrust section. Light-load floor: Pu = 14 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 54317; the number is 8 % of the 174 kN dynamic rating. Static-first selection data: 405 kN C0 spread across the 95.2 mm stack gives 4.3 kN of static rating per height millimetre, and the 7950 g mass/C0 ratio is about 20 g per static kN — crane-hook and screw positions are normally sized on these two figures. Pitch-diameter arithmetic: dm = (70+150)/2 = 110.0 mm; at the 1,500 r/min limiting speed that corresponds to roughly 165k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Load balance: C0 405 kN against C 174 kN gives a 2.33 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 14 kN enters the adjusted-life check. Bidirectional self-aligning note: TWO U seat washers are required for this order number, one behind each housing washer, and the catalogue H1 height includes them on both sides of the stack; the spherical interfaces accept initial misalignment in either load direction but are not pivots for continuous oscillation. Bill of materials for this page is 54317 plus TWO × U 317; the 105 mm H1 stack sits in a housing whose two register faces should be machined in one clamping to keep both spherical axes coincident.", "applications": [ "large vertical-pump thrust with up-thrust events", "heavy turret and slewing adjustments", "large two-direction screwdown screws" ], "failure_modes": [ "ball skidding on the momentarily unloaded side during rapid thrust reversal below the minimum load", "thermal lock-up when differential expansion removes the end play of the tighter-loaded side", "total loss of the aligning function after paint, scale or abrasive dust fills the sphered contact", "one-side spherical seizure after grit fills the interface of the U washer on the less-loaded side", "raceway indentation from driving the bearing home through the ball set rather than the washer face", "abrasive scoring of washers and balls when the open arrangement runs without external sealing" ], "pitfalls": [ "The two spherical interfaces accommodate initial misalignment in either load direction but must stay clean, greased and static — continuous rocking frets the sphered contacts of even the 405 kN static-rated set.", "Replacement ordering is THREE numbers: 54317 plus two pieces of U 317; quoting only the bearing leaves the sphered backs running on bare registers.", "Assembly is a five-component stack (central shaft washer, two cage sets, two sphered housing washers) plus the two U seat washers in the housing registers; dry-build the arrangement by hand first to confirm both sides swivel freely.", "Minimum load factor A 1.1 applies to both load directions, and both brass pressed cage sets need lubricant reaching the upper track on a vertical shaft.", "The 174/405 kN figures belong to 54317 specifically (the double sphered pressed steel execution of 54317); suffixed, sphered and counterpart-series order numbers are separate articles, and U 317 is ordered separately, so write the complete designation on the order and the maintenance record." ], "faq": [ { "q": "What are the dimensions and catalogue data of 54317?", "a": "Boundary dimensions to ISO 104: bore 70 mm, OD 150 mm, height 95.2 mm (H1 105 mm installed with the U 317 seat washer); weight 7950 g. Load figures from SKF 17000: dynamic 174 kN, static 405 kN, fatigue limit 14 kN; reference speed 1,100 r/min (thermal) and limiting speed 1,500 r/min (mechanical)." }, { "q": "What does the designation 54317 mean?", "a": "bore-coding caveat: on 52/54 double-direction bearings the last two digits are an order-number code, not ×5 millimetres — this size carries a 70 mm bore per the ISO 104 table, and guessing from the code gives the wrong shaft. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. 5 = thrust ball bearing, 4 = double direction with sphered seating surfaces." }, { "q": "What is the difference between 54317 and two single-direction 53-series bearings?", "a": "54317 is one factory-matched bidirectional unit with a central shaft washer; two 53-series bearings would need two shaft seats and roughly twice the axial space with separate fits. The 54-series is the compact reversing counterpart, not a stacking kit." }, { "q": "Does the spherical seat work while the shaft rocks continuously?", "a": "No — it accommodates initial static misalignment only. Continuous oscillation frets the sphered contacts even with C0 405 kN in reserve; keep the interfaces greased and clean and design genuine pivots separately." } ], "cross_ref": [ { "equiv_sku": "54317", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "54317", "54317 + U 317" ], "locale_variants": {} }, { "sku": "54420-M", "brand": "SKF", "manufacturer_designation": "54420 M", "series": "54400-series", "type": "thrust_ball", "d_mm": 80, "D_mm": 210, "B_mm": 159.9, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 371, "static_load_kN": 1060, "fatigue_load_limit_kN": 31.5, "reference_speed_rpm": 700, "limiting_speed_rpm": 950, "max_rpm": 950, "weight_g": 29000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Listed in SKF 17000 chapter 5, 54420 M is an ISO 104 double-direction thrust ball bearing, 80 mm bore and 210 mm OD, with a sphered housing washer and U seat washer, standing 159.9 mm high before installation. Construction is a five-component stack: one central shaft washer with tracks on both faces, two outward-facing housing washers and two cage sets, which lets one housing recess accept thrust from either direction. note the bore of 54420 M is 80 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. Envelope 80×210×159.9 mm (3.15×8.268×6.295 in), 65.0 mm radial section, C 371 kN, C0 1060 kN, Pu 31.5 kN. Mounted height H1 176 mm includes the U 420 seat washer; the bearing alone is 159.9 mm high. reference speed 700 r/min (thermal) and limiting speed 950 r/min (mechanical), catalogue mass 29000 g. Speed band width for this size is 250 r/min between reference and limiting (1.36× ratio); lubrication, preload and heat removal decide where inside that band 54420 M can actually run. Minimum-load arithmetic: with dm ≈ 145.0 mm and factor A 5.8, Fam ≈ A·(n·dm/1000)² at the 700 r/min reference speed is about 59.8 kN for 54420 M; below that preload the balls skid and smear the tracks. Washer-annulus check: the π/4·(D²−d²) contact annulus of 54420 M covers about 29,610 mm², distributing C0 1060 kN over a mean track circle of π·dm ≈ 456 mm. Light-load floor: Pu = 31.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 54420 M; the number is 8 % of the 371 kN dynamic rating. Stack/annulus proportions: the 159.9 mm axial stack over the 29,610 mm² washer annulus gives 5.40 mm of height per annular square millimetre ×10⁻³, and at 29000 g the bearing holds about 36.6 kN of C0 per kilogram. Heavy bidirectional self-aligning note: the two machined brass cage sets and the two sphered housing washer / U seat-washer pairs make this the heaviest standard thrust-ball execution of its bore — check both spherical interfaces for fretting at overhaul and confirm both U washers are the catalogue-matched designations before reassembly. The heaviest self-aligning thrust-ball execution of its bore: 29000 g, two machined brass cage sets and two sphered washer pairs at 176 mm installed height — plan lifting fixtures and the two U 420 articles before shutdown work starts.", "applications": [ "heavy reversing hook blocks needing self-aligning seats", "large vertical-pump thrust with up-thrust events", "winch drives with bidirectional thrust on welded frames" ], "failure_modes": [ "thermal lock-up when differential expansion removes the end play of the tighter-loaded side", "one-side track spalling when reversing duty dwells predominantly in one direction and only one cage set accumulates cycles", "point-contact destruction of the housing register when a sphered washer is operated directly on a flat face without its U seat washer", "asymmetric cage wear when reversing duty loads one brass cage set far more often than the other", "false brinelling of the stationary tracks while the machine stands under vibration", "rolling-contact fatigue spalling after the L10 life at the actual thrust load is exceeded" ], "pitfalls": [ "The 371/1060 kN ratings assume the spherical contacts are free to find their seat — a painted-over or shimmed U washer fixes the angle and turns the self-aligning bearing into an edge-loaded one.", "Assembly is a five-component stack (central shaft washer, two cage sets, two sphered housing washers) plus the two U seat washers in the housing registers; dry-build the arrangement by hand first to confirm both sides swivel freely.", "Order TWO seat washers for 54420 M — the designation U 420 pairs with one side and a second U washer (same number) with the other; the catalogue 176 mm H1 includes both.", "The two spherical interfaces accommodate initial misalignment in either load direction but must stay clean, greased and static — continuous rocking frets the sphered contacts of even the 1060 kN static-rated set.", "Ordering discipline for 54420: the catalogue page quotes 54420 M plus U 420 and its 371/1060 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 54420-M?", "a": "The catalogue envelope is 80×210×159.9 mm plus the 16.1 mm the U 420 seat washer adds to reach H1 176 mm, mass 29000 g; ratings C 371 kN / C0 1060 kN / Pu 31.5 kN, reference speed 700 r/min (thermal) and limiting speed 950 r/min (mechanical)." }, { "q": "What does the designation 54420 M mean?", "a": "note the bore of 54420 M is 80 mm by the dimension table: the double-direction series was deliberately aligned to the 51/53 washer sets with shifted codes, so the familiar 04=20 arithmetic does not apply here. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. 5 = thrust ball bearing, 4 = double direction with sphered seating surfaces." }, { "q": "What loads can 54420-M take?", "a": "Pure axial load in both directions: C 371 kN, C0 1060 kN, Pu 31.5 kN, with the same minimum-load rule (factor A 5.8) in each direction; radial load is excluded." }, { "q": "How are the two U washers ordered and fitted?", "a": "Order two pieces of U 420 and seat one flat-backed in each housing register with the concave faces towards the sphered housing washers; check both interfaces swivel freely before fitting the central shaft washer, and verify the mounted stack measures the 176 mm H1." } ], "cross_ref": [ { "equiv_sku": "54420", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "54420-M", "54420 M", "54420 M + U 420" ], "locale_variants": {} }, { "sku": "YAR-203-12-2F", "brand": "SKF", "manufacturer_designation": "YAR 203/12-2F", "series": "YAR2-series", "type": "insert", "d_mm": 12, "D_mm": 40, "B_mm": 27.4, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 9.56, "static_load_kN": 4.75, "fatigue_load_limit_kN": 0.2, "limiting_speed_rpm": 9500, "max_rpm": 9500, "weight_g": 120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 203/12-2F is a SKF insert bearing (Y-bearing) for a 12 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 40 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the slash tail names a non-standard metric bore directly: YAR 203/12 is the 12 mm bore execution of the size series. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 12x40x27.4 mm (0.472x1.575x1.079 in), outer ring 12 mm wide, C 9.56 kN, C0 4.75 kN, Pu 0.2 kN. The catalogue publishes a single speed ceiling, the limiting speed: 9,500 r/min; mass 120 g. Mass-to-load ratio for YAR-203-12-2F: 12.552 g of catalogue mass per rated kN of C, and 10 g per millimetre of bore — useful when comparing executions of the same 12x40 mm envelope on the drawing. Outer-vs-overall width: the outer ring is 12 mm wide inside the 27.4 mm total, so the extended inner ring accounts for 0.562 of the overall width (7.7 mm of axial projection per side). Bore-to-OD planning: OD 40 over bore 12 is a 3.333x step, while bore/overall-width gives 0.438; the spherical seat in the matching Y-housing must be specified to the 40 mm OD, not to a cylindrical housing bore. Rating split for the maintenance file: dynamic 9.56 kN (L10), static 4.75 kN (s0 shock check), fatigue 0.2 kN (adjusted life) — three separate uses for YAR 203/12-2F, none interchangeable with another. Fillet discipline: the printed r_min 0.3 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 12x40 mm insert on its chamfer tilts the whole spherical seat. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-203-12-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 14 mm radial section.", "applications": [ "textile machinery rollers", "small agricultural augers", "fan and blower pillow blocks" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Do not specify the 12 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 15.9 mm s1 dimension is the screw seating geometry inside the 15.4 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAR 203/12-2F as the grub two f execution; other order numbers of the YAR 203/12 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-203-12-2F?", "a": "Boundary dimensions: bore 12 mm, sphered OD 40 mm, overall width 27.4 mm; weight 120 g. Loads: dynamic 9.56 kN, static 4.75 kN, fatigue 0.2 kN; the only published speed is the 9,500 r/min limiting value." }, { "q": "What does the designation YAR 203/12-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the slash tail names a non-standard metric bore directly: YAR 203/12 is the 12 mm bore execution of the size series. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-203-12-2F", "YAR 203/12-2F" ], "locale_variants": {} }, { "sku": "YAR-203-15-2F", "brand": "SKF", "manufacturer_designation": "YAR 203/15-2F", "series": "YAR2-series", "type": "insert", "d_mm": 15, "D_mm": 40, "B_mm": 27.4, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 9.56, "static_load_kN": 4.75, "fatigue_load_limit_kN": 0.2, "limiting_speed_rpm": 9500, "max_rpm": 9500, "weight_g": 110, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 203/15-2F is a SKF insert bearing (Y-bearing) for a 15 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 40 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the slash tail names a non-standard metric bore directly: YAR 203/15 is the 15 mm bore execution of the size series. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 15x40x27.4 mm (0.591x1.575x1.079 in), outer ring 12 mm wide, C 9.56 kN, C0 4.75 kN, Pu 0.2 kN. The catalogue publishes a single speed ceiling, the limiting speed: 9,500 r/min; mass 110 g. Bore-to-OD planning: OD 40 over bore 15 is a 2.667x step, while bore/overall-width gives 0.547; the spherical seat in the matching Y-housing must be specified to the 40 mm OD, not to a cylindrical housing bore. Capacity density: 9.56 kN from 0.110 kg of bearing steel is about 86.909 kN per kilogram, and per width millimetre the 27.4 mm unit carries 0.349 kN of dynamic capacity. Mass-to-load ratio for YAR-203-15-2F: 11.506 g of catalogue mass per rated kN of C, and 7.333 g per millimetre of bore — useful when comparing executions of the same 15x40 mm envelope on the drawing. Static-first planning: the 0.173 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 15 mm shaft, not the 9.56 kN L10 value. Grease-life arithmetic is dominated by speed: at dn approx 2.61x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 15 mm shaft inside the 27.4 mm total width while the outer ring is only 12 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "textile machinery rollers", "fan and blower pillow blocks", "light conveyors and small belt take-ups" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The 15.9 mm s1 dimension is the screw seating geometry inside the 15.4 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 15 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 9.56/4.75 kN figures belong specifically to YAR 203/15-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-203-15-2F?", "a": "Boundary dimensions: bore 15 mm, sphered OD 40 mm, overall width 27.4 mm; weight 110 g. Loads: dynamic 9.56 kN, static 4.75 kN, fatigue 0.2 kN; the only published speed is the 9,500 r/min limiting value." }, { "q": "What does the designation YAR 203/15-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the slash tail names a non-standard metric bore directly: YAR 203/15 is the 15 mm bore execution of the size series. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "How do the set screws lock the 15 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-203-15-2F", "YAR 203/15-2F" ], "locale_variants": {} }, { "sku": "YAT-203", "brand": "SKF", "manufacturer_designation": "YAT 203", "series": "YAR2-series", "type": "insert", "d_mm": 17, "D_mm": 40, "B_mm": 22.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 9.56, "static_load_kN": 4.75, "fatigue_load_limit_kN": 0.2, "limiting_speed_rpm": 9500, "max_rpm": 9500, "weight_g": 80, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAT 203 is a grub-screw insert bearing with the inner ring extended on one side, 17x40x22.1 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. the size code 203 carries the usual bore arithmetic — 17 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 17x40x22.1 mm (0.669x1.575x0.87 in), outer ring 12 mm wide, C 9.56 kN, C0 4.75 kN, Pu 0.2 kN. The catalogue publishes a single speed ceiling, the limiting speed: 9,500 r/min; mass 80 g. Load balance for documentation: C0 4.75 kN against C 9.56 kN gives a 0.497 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Speed ceiling of 9,500 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Pitch-diameter arithmetic: dm = (17+40)/2 = 28.5 mm; at the 9,500 r/min limiting speed the ball set runs at dn approx 2.71x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Envelope arithmetic: the radial section from 17 mm bore to 40 mm OD is 11.5 mm; dividing C 9.56 kN by that section gives 0.831 kN per section millimetre, and the 22.1 mm overall width is 1.922x the section. Outer-vs-overall width: the outer ring is 12 mm wide inside the 22.1 mm total, so the extended inner ring accounts for 0.457 of the overall width (10.1 mm of axial projection on the locking side). Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Set-screw geometry on this size: the two 120 deg screws bear on the 17 mm shaft inside the 22.1 mm total width while the outer ring is only 12 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "light conveyors and small belt take-ups", "small agricultural augers", "textile machinery rollers" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 17 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 15.9 mm s1 dimension is the screw seating geometry inside the 10.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAT 203 as the grub one open execution; other order numbers of the YAT 203 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-203?", "a": "The catalogue envelope is 17x40x22.1 mm with a spherical outside surface; mass 80 g. Ratings C 9.56/4.75 kN, Pu 0.2 kN, limiting speed 9,500 r/min." }, { "q": "What does the designation YAT 203 mean?", "a": "YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. the size code 203 carries the usual bore arithmetic — 17 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-203", "YAT 203" ], "locale_variants": {} }, { "sku": "YAR-203-2F", "brand": "SKF", "manufacturer_designation": "YAR 203-2F", "series": "YAR2-series", "type": "insert", "d_mm": 17, "D_mm": 40, "B_mm": 27.4, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 9.56, "static_load_kN": 4.75, "fatigue_load_limit_kN": 0.2, "limiting_speed_rpm": 9500, "max_rpm": 9500, "weight_g": 100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 203-2F is a SKF insert bearing (Y-bearing) for a 17 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 40 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 203 carries the usual bore arithmetic — 17 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 17x40x27.4 mm (0.669x1.575x1.079 in), outer ring 12 mm wide, C 9.56 kN, C0 4.75 kN, Pu 0.2 kN. The catalogue publishes a single speed ceiling, the limiting speed: 9,500 r/min; mass 100 g. Mass-to-load ratio for YAR-203-2F: 10.46 g of catalogue mass per rated kN of C, and 5.882 g per millimetre of bore — useful when comparing executions of the same 17x40 mm envelope on the drawing. Width accounting on this execution: 27.4 mm overall and 12 mm outer-ring width leave the housing designer 15.4 mm of inner-ring projection to accommodate the locking arrangement. Pitch-diameter arithmetic: dm = (17+40)/2 = 28.5 mm; at the 9,500 r/min limiting speed the ball set runs at dn approx 2.71x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Fillet discipline: the printed r_min 0.3 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 17x40 mm insert on its chamfer tilts the whole spherical seat. Rating split for the maintenance file: dynamic 9.56 kN (L10), static 4.75 kN (s0 shock check), fatigue 0.2 kN (adjusted life) — three separate uses for YAR 203-2F, none interchangeable with another. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-203-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 11.5 mm radial section.", "applications": [ "textile machinery rollers", "small agricultural augers", "fan and blower pillow blocks" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 15.9 mm s1 dimension is the screw seating geometry inside the 15.4 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 17 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Ordering discipline for the 17 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-203-2F?", "a": "Boundary dimensions: bore 17 mm, sphered OD 40 mm, overall width 27.4 mm; weight 100 g. Loads: dynamic 9.56 kN, static 4.75 kN, fatigue 0.2 kN; the only published speed is the 9,500 r/min limiting value." }, { "q": "What does the designation YAR 203-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 203 carries the usual bore arithmetic — 17 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-203-2F", "YAR 203-2F" ], "locale_variants": {} }, { "sku": "YAT-204", "brand": "SKF", "manufacturer_designation": "YAT 204", "series": "YAR2-series", "type": "insert", "d_mm": 20, "D_mm": 47, "B_mm": 25.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 130, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAT 204 is a SKF insert bearing (Y-bearing) for a 20 mm shaft: grub-screw insert bearing with the inner ring extended on one side, built to the ISO 15 diameter-series envelope with a sphered OD of 47 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings. Envelope 20x47x25.5 mm (0.787x1.85x1.004 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. The catalogue publishes a single speed ceiling, the limiting speed: 8,500 r/min; mass 130 g. Static-first planning: the 0.257 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 20 mm shaft, not the 12.7 kN L10 value. Grease-life arithmetic is dominated by speed: at dn approx 2.85x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 20x47 mm insert on its chamfer tilts the whole spherical seat. Pitch-diameter arithmetic: dm = (20+47)/2 = 33.5 mm; at the 8,500 r/min limiting speed the ball set runs at dn approx 2.85x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Capacity density: 12.7 kN from 0.130 kg of bearing steel is about 97.692 kN per kilogram, and per width millimetre the 25.5 mm unit carries 0.498 kN of dynamic capacity. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Service tip for YAT-204: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 13.5 mm radial section.", "applications": [ "light conveyors and small belt take-ups", "fan and blower pillow blocks", "small agricultural augers" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The 18.3 mm s1 dimension is the screw seating geometry inside the 11.5 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 20 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 12.7/6.55 kN figures belong specifically to YAT 204; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-204?", "a": "Boundary dimensions: bore 20 mm, sphered OD 47 mm, overall width 25.5 mm; weight 130 g. Loads: dynamic 12.7 kN, static 6.55 kN, fatigue 0.28 kN; the only published speed is the 8,500 r/min limiting value." }, { "q": "What does the designation YAT 204 mean?", "a": "reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-204", "YAT 204" ], "locale_variants": {} }, { "sku": "YAR-204-2RF-HV", "brand": "SKF", "manufacturer_designation": "YAR 204-2RF/HV", "series": "YAR2-series", "type": "insert", "d_mm": 20, "D_mm": 47, "B_mm": 31, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 10.8, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 204-2RF/HV is a grub-screw insert bearing with the inner ring extended on both sides, 20x47x31 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed. Envelope 20x47x31 mm (0.787x1.85x1.22 in), outer ring 14 mm wide, C 10.8 kN, C0 6.55 kN, Pu 0.28 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,000 r/min; mass 150 g. At the printed limiting speed of 5,000 r/min the mean diameter dm = 33.5 mm implies dn about 1.68x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Rating split for the maintenance file: dynamic 10.8 kN (L10), static 6.55 kN (s0 shock check), fatigue 0.28 kN (adjusted life) — three separate uses for YAR 204-2RF/HV, none interchangeable with another. Static-first planning: the 0.211 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 20 mm shaft, not the 10.8 kN L10 value. Fatigue-limit check: Pu 0.28 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAR 204-2RF/HV — most belt-driven mounted-unit loads sit comfortably under 2.593 % of C. Mass-to-load ratio for YAR-204-2RF-HV: 13.889 g of catalogue mass per rated kN of C, and 7.5 g per millimetre of bore — useful when comparing executions of the same 20x47 mm envelope on the drawing. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Set-screw geometry on this size: the two 120 deg screws bear on the 20 mm shaft inside the 31 mm total width while the outer ring is only 14 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small agricultural augers", "fan and blower pillow blocks", "textile machinery rollers" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 20 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 18.3 mm s1 dimension is the screw seating geometry inside the 17 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 20 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-204-2RF-HV?", "a": "The catalogue envelope is 20x47x31 mm with a spherical outside surface; mass 150 g. Ratings C 10.8/6.55 kN, Pu 0.28 kN, limiting speed 5,000 r/min." }, { "q": "What does the designation YAR 204-2RF/HV mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed." }, { "q": "How do the set screws lock the 20 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-204-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-204", "equiv_brand": "SKF", "level": "partial", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (10.8/6.55 kN vs 12.7/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (10.8/6.55 kN vs 12.7/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (10.8/6.55 kN vs 12.7/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (10.8/6.55 kN vs 12.7/6.55 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-204-2RF-HV", "YAR 204-2RF/HV" ], "locale_variants": {} }, { "sku": "YAR-204-2RFGR-HV", "brand": "SKF", "manufacturer_designation": "YAR 204-2RFGR/HV", "series": "YAR2-series", "type": "insert", "d_mm": 20, "D_mm": 47, "B_mm": 31, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 10.8, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 204-2RFGR/HV is SKF's 20 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 20x47x31 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. /HV identifies the stainless-steel, food-industry execution: stainless bearing components, food-compatible rubber in the seal/flinger set and food-grade grease fill — the catalogue ratings are correspondingly below the standard steel version, and the GR marking adds the lubrication groove in the sphered outside surface on the locking side. Envelope 20x47x31 mm (0.787x1.85x1.22 in), outer ring 14 mm wide, C 10.8 kN, C0 6.55 kN, Pu 0.28 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,000 r/min; mass 150 g. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 20x47 mm insert on its chamfer tilts the whole spherical seat. Mass-to-load ratio for YAR-204-2RFGR-HV: 13.889 g of catalogue mass per rated kN of C, and 7.5 g per millimetre of bore — useful when comparing executions of the same 20x47 mm envelope on the drawing. Outer-vs-overall width: the outer ring is 14 mm wide inside the 31 mm total, so the extended inner ring accounts for 0.548 of the overall width (8.5 mm of axial projection per side). Load balance for documentation: C0 6.55 kN against C 10.8 kN gives a 0.606 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Rating split for the maintenance file: dynamic 10.8 kN (L10), static 6.55 kN (s0 shock check), fatigue 0.28 kN (adjusted life) — three separate uses for YAR 204-2RFGR/HV, none interchangeable with another. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Set-screw geometry on this size: the two 120 deg screws bear on the 20 mm shaft inside the 31 mm total width while the outer ring is only 14 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "textile machinery rollers", "fan and blower pillow blocks", "light conveyors and small belt take-ups" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "The 18.3 mm s1 dimension is the screw seating geometry inside the 17 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 20 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 10.8/6.55 kN figures belong specifically to YAR 204-2RFGR/HV; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-204-2RFGR-HV?", "a": "YAR 204-2RFGR/HV measures 20 mm bore x 47 mm OD x 31 mm overall width (outer ring 14 mm wide), 0.787 x 1.85 x 1.22 in; mass about 150 g. SKF 17000 ratings: C 10.8 kN, C0 6.55 kN, Pu 0.28 kN, limiting speed 5,000 r/min." }, { "q": "What does the designation YAR 204-2RFGR/HV mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. /HV identifies the stainless-steel, food-industry execution: stainless bearing components, food-compatible rubber in the seal/flinger set and food-grade grease fill — the catalogue ratings are correspondingly below the standard steel version, and the GR marking adds the lubrication groove in the sphered outside surface on the locking side." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-204-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-204", "equiv_brand": "SKF", "level": "partial", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (10.8/6.55 kN vs 12.7/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (10.8/6.55 kN vs 12.7/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (10.8/6.55 kN vs 12.7/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (10.8/6.55 kN vs 12.7/6.55 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-204-2RFGR-HV", "YAR 204-2RFGR/HV" ], "locale_variants": {} }, { "sku": "YARAG-204", "brand": "SKF", "manufacturer_designation": "YARAG 204", "series": "YAR2-series", "type": "insert", "d_mm": 20, "D_mm": 47, "B_mm": 31, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YARAG 204 is a SKF insert bearing (Y-bearing) for a 20 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 47 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution. Envelope 20x47x31 mm (0.787x1.85x1.22 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,800 r/min; mass 150 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 28.2 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Grease-life arithmetic is dominated by speed: at dn approx 0.60x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the AG variant caps speed so aggressively, and high-temperature mounts shorten both even when load is light. At the printed limiting speed of 1,800 r/min the mean diameter dm = 33.5 mm implies dn about 0.60x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Spherical-seat note in numbers: the 47 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 33.5 = 105.243 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Pitch-diameter arithmetic: dm = (20+47)/2 = 33.5 mm; at the 1,800 r/min limiting speed the ball set runs at dn approx 0.60x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Set-screw geometry on this size: the two 120 deg screws bear on the 20 mm shaft inside the 31 mm total width while the outer ring is only 14 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small agricultural augers", "fan and blower pillow blocks", "textile machinery rollers" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The 18.3 mm s1 dimension is the screw seating geometry inside the 17 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 20 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 12.7/6.55 kN figures belong specifically to YARAG 204; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-204?", "a": "Boundary dimensions: bore 20 mm, sphered OD 47 mm, overall width 31 mm; weight 150 g. Loads: dynamic 12.7 kN, static 6.55 kN, fatigue 0.28 kN; the only published speed is the 1,800 r/min limiting value." }, { "q": "What does the designation YARAG 204 mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-204-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (12.7/6.55 kN vs 10.8/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (12.7/6.55 kN vs 10.8/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-204-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-204-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-204", "YARAG 204" ], "locale_variants": {} }, { "sku": "YAR-204-2RF", "brand": "SKF", "manufacturer_designation": "YAR 204-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 20, "D_mm": 47, "B_mm": 31, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 204-2RF is a grub-screw insert bearing with the inner ring extended on both sides, 20x47x31 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2RF external design combines contact nitrile seals with rubberized additional flingers on both sides for a tighter labyrinth than the plain-flinger -2F execution. Envelope 20x47x31 mm (0.787x1.85x1.22 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,000 r/min; mass 150 g. The s1 18.3 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Bore-to-OD planning: OD 47 over bore 20 is a 2.35x step, while bore/overall-width gives 0.645; the spherical seat in the matching Y-housing must be specified to the 47 mm OD, not to a cylindrical housing bore. Grease-life arithmetic is dominated by speed: at dn approx 1.68x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Load balance for documentation: C0 6.55 kN against C 12.7 kN gives a 0.516 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Rating split for the maintenance file: dynamic 12.7 kN (L10), static 6.55 kN (s0 shock check), fatigue 0.28 kN (adjusted life) — three separate uses for YAR 204-2RF, none interchangeable with another. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Set-screw geometry on this size: the two 120 deg screws bear on the 20 mm shaft inside the 31 mm total width while the outer ring is only 14 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "light conveyors and small belt take-ups", "textile machinery rollers", "small agricultural augers" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The 18.3 mm s1 dimension is the screw seating geometry inside the 17 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 20 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 12.7/6.55 kN figures belong specifically to YAR 204-2RF; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-204-2RF?", "a": "The catalogue envelope is 20x47x31 mm with a spherical outside surface; mass 150 g. Ratings C 12.7/6.55 kN, Pu 0.28 kN, limiting speed 5,000 r/min." }, { "q": "What does the designation YAR 204-2RF mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2RF external design combines contact nitrile seals with rubberized additional flingers on both sides for a tighter labyrinth than the plain-flinger -2F execution." }, { "q": "How do the set screws lock the 20 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-204-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (12.7/6.55 kN vs 10.8/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (12.7/6.55 kN vs 10.8/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-204", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 204 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-204-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-204-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-204-2RF", "YAR 204-2RF" ], "locale_variants": {} }, { "sku": "YAR-204-2RF-VE495", "brand": "SKF", "manufacturer_designation": "YAR 204-2RF/VE495", "series": "YAR2-series", "type": "insert", "d_mm": 20, "D_mm": 47, "B_mm": 31, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 204-2RF/VE495 is a grub-screw insert bearing with the inner ring extended on both sides, 20x47x31 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. VE495 denotes galvanized rings plus food-compatible sealing components and grease, aimed at humid, cleaned-down installations rather than submerged chemical duty. Envelope 20x47x31 mm (0.787x1.85x1.22 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,000 r/min; mass 150 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 28.2 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Outer-vs-overall width: the outer ring is 14 mm wide inside the 31 mm total, so the extended inner ring accounts for 0.548 of the overall width (8.5 mm of axial projection per side). Width accounting on this execution: 31 mm overall and 14 mm outer-ring width leave the housing designer 17 mm of inner-ring projection to accommodate the locking arrangement. Static-first planning: the 0.211 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 20 mm shaft, not the 12.7 kN L10 value. Capacity density: 12.7 kN from 0.150 kg of bearing steel is about 84.667 kN per kilogram, and per width millimetre the 31 mm unit carries 0.41 kN of dynamic capacity. Zinc-coated food-range note: the VE495 plating is a functional surface, not cosmetic; clean the bore and shaft WITHOUT steel brushes or aggressive descalers, mount dry or with the approved food-grade mounting paste, and touch up damaged plating spots before commissioning the wash-down area. Set-screw geometry on this size: the two 120 deg screws bear on the 20 mm shaft inside the 31 mm total width while the outer ring is only 14 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small agricultural augers", "textile machinery rollers", "fan and blower pillow blocks" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The 18.3 mm s1 dimension is the screw seating geometry inside the 17 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 20 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 12.7/6.55 kN figures belong specifically to YAR 204-2RF/VE495; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-204-2RF-VE495?", "a": "The catalogue envelope is 20x47x31 mm with a spherical outside surface; mass 150 g. Ratings C 12.7/6.55 kN, Pu 0.28 kN, limiting speed 5,000 r/min." }, { "q": "What does the designation YAR 204-2RF/VE495 mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. VE495 denotes galvanized rings plus food-compatible sealing components and grease, aimed at humid, cleaned-down installations rather than submerged chemical duty." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-204-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (12.7/6.55 kN vs 10.8/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (12.7/6.55 kN vs 10.8/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-204", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 204 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-204-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-204-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-204-2RF-VE495", "YAR 204-2RF/VE495" ], "locale_variants": {} }, { "sku": "YAR-204-2F", "brand": "SKF", "manufacturer_designation": "YAR 204-2F", "series": "YAR2-series", "type": "insert", "d_mm": 20, "D_mm": 47, "B_mm": 31, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 204-2F is SKF's 20 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 20x47x31 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 20x47x31 mm (0.787x1.85x1.22 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. The catalogue publishes a single speed ceiling, the limiting speed: 8,500 r/min; mass 150 g. Bore-to-OD planning: OD 47 over bore 20 is a 2.35x step, while bore/overall-width gives 0.645; the spherical seat in the matching Y-housing must be specified to the 47 mm OD, not to a cylindrical housing bore. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 20x47 mm insert on its chamfer tilts the whole spherical seat. Outer-vs-overall width: the outer ring is 14 mm wide inside the 31 mm total, so the extended inner ring accounts for 0.548 of the overall width (8.5 mm of axial projection per side). Mass-to-load ratio for YAR-204-2F: 11.811 g of catalogue mass per rated kN of C, and 7.5 g per millimetre of bore — useful when comparing executions of the same 20x47 mm envelope on the drawing. The s1 18.3 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 20 mm shaft inside the 31 mm total width while the outer ring is only 14 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "textile machinery rollers", "fan and blower pillow blocks", "light conveyors and small belt take-ups" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The 18.3 mm s1 dimension is the screw seating geometry inside the 17 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 20 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 12.7/6.55 kN figures belong specifically to YAR 204-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-204-2F?", "a": "YAR 204-2F measures 20 mm bore x 47 mm OD x 31 mm overall width (outer ring 14 mm wide), 0.787 x 1.85 x 1.22 in; mass about 150 g. SKF 17000 ratings: C 12.7 kN, C0 6.55 kN, Pu 0.28 kN, limiting speed 8,500 r/min." }, { "q": "What does the designation YAR 204-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "How is YAR-204-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 20 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-204-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (12.7/6.55 kN vs 10.8/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (12.7/6.55 kN vs 10.8/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-204", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 204 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-204-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-204-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-204-2F", "YAR 204-2F" ], "locale_variants": {} }, { "sku": "YAT-205", "brand": "SKF", "manufacturer_designation": "YAT 205", "series": "YAR2-series", "type": "insert", "d_mm": 25, "D_mm": 52, "B_mm": 27.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 160, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAT 205 is a grub-screw insert bearing with the inner ring extended on one side, 25x52x27.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 25x52x27.2 mm (0.984x2.047x1.071 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 7,000 r/min; mass 160 g. At the printed limiting speed of 7,000 r/min the mean diameter dm = 38.5 mm implies dn about 2.69x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Pitch-diameter arithmetic: dm = (25+52)/2 = 38.5 mm; at the 7,000 r/min limiting speed the ball set runs at dn approx 2.69x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Static-first planning: the 0.287 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 25 mm shaft, not the 14 kN L10 value. The s1 19.5 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Mass-to-load ratio for YAT-205: 11.429 g of catalogue mass per rated kN of C, and 6.4 g per millimetre of bore — useful when comparing executions of the same 25x52 mm envelope on the drawing. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Service tip for YAT-205: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 13.5 mm radial section.", "applications": [ "garden and groundcare equipment", "trough conveyor idler drives", "ventilation and extraction fans" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Do not specify the 25 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 19.5 mm s1 dimension is the screw seating geometry inside the 12.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAT 205 as the grub one open execution; other order numbers of the YAT 205 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-205?", "a": "The catalogue envelope is 25x52x27.2 mm with a spherical outside surface; mass 160 g. Ratings C 14/7.8 kN, Pu 0.335 kN, limiting speed 7,000 r/min." }, { "q": "What does the designation YAT 205 mean?", "a": "YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAT-205 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAT-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x27.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAT 205-100 is the grub-screw locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-205", "YAT 205" ], "locale_variants": {} }, { "sku": "YAR-205-2RF-HV", "brand": "SKF", "manufacturer_designation": "YAR 205-2RF/HV", "series": "YAR2-series", "type": "insert", "d_mm": 25, "D_mm": 52, "B_mm": 34.1, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 11.9, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 205-2RF/HV is a SKF insert bearing (Y-bearing) for a 25 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 52 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part. Envelope 25x52x34.1 mm (0.984x2.047x1.343 in), outer ring 15 mm wide, C 11.9 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 190 g. Bore-to-OD planning: OD 52 over bore 25 is a 2.08x step, while bore/overall-width gives 0.733; the spherical seat in the matching Y-housing must be specified to the 52 mm OD, not to a cylindrical housing bore. The s1 19.8 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Grease-life arithmetic is dominated by speed: at dn approx 1.66x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Mass-to-load ratio for YAR-205-2RF-HV: 15.966 g of catalogue mass per rated kN of C, and 7.6 g per millimetre of bore — useful when comparing executions of the same 25x52 mm envelope on the drawing. Selection figures for YAR 205-2RF/HV: C0/C is 0.655, Pu 0.335 kN is 2.815 % of the 11.9 kN dynamic rating, and the 190 g catalogue mass works out to roughly 7.6 g per millimetre of the 25 mm bore. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Set-screw geometry on this size: the two 120 deg screws bear on the 25 mm shaft inside the 34.1 mm total width while the outer ring is only 15 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "garden and groundcare equipment", "ventilation and extraction fans", "trough conveyor idler drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 25 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 19.8 mm s1 dimension is the screw seating geometry inside the 19.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 25 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-205-2RF-HV?", "a": "Boundary dimensions: bore 25 mm, sphered OD 52 mm, overall width 34.1 mm; weight 190 g. Loads: dynamic 11.9 kN, static 7.8 kN, fatigue 0.335 kN; the only published speed is the 4,300 r/min limiting value." }, { "q": "What does the designation YAR 205-2RF/HV mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part." }, { "q": "How do the set screws lock the 25 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-205-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-205", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-100-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-205-100", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-205-2RF-HV", "YAR 205-2RF/HV" ], "locale_variants": {} }, { "sku": "YAR-205-2RFGR-HV", "brand": "SKF", "manufacturer_designation": "YAR 205-2RFGR/HV", "series": "YAR2-series", "type": "insert", "d_mm": 25, "D_mm": 52, "B_mm": 34.1, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 11.9, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 205-2RFGR/HV is a grub-screw insert bearing with the inner ring extended on both sides, 25x52x34.1 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed. Envelope 25x52x34.1 mm (0.984x2.047x1.343 in), outer ring 15 mm wide, C 11.9 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 190 g. Mass-to-load ratio for YAR-205-2RFGR-HV: 15.966 g of catalogue mass per rated kN of C, and 7.6 g per millimetre of bore — useful when comparing executions of the same 25x52 mm envelope on the drawing. Selection figures for YAR 205-2RFGR/HV: C0/C is 0.655, Pu 0.335 kN is 2.815 % of the 11.9 kN dynamic rating, and the 190 g catalogue mass works out to roughly 7.6 g per millimetre of the 25 mm bore. Envelope arithmetic: the radial section from 25 mm bore to 52 mm OD is 13.5 mm; dividing C 11.9 kN by that section gives 0.881 kN per section millimetre, and the 34.1 mm overall width is 2.526x the section. Pitch-diameter arithmetic: dm = (25+52)/2 = 38.5 mm; at the 4,300 r/min limiting speed the ball set runs at dn approx 1.66x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Rating split for the maintenance file: dynamic 11.9 kN (L10), static 7.8 kN (s0 shock check), fatigue 0.335 kN (adjusted life) — three separate uses for YAR 205-2RFGR/HV, none interchangeable with another. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-205-2RFGR-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 13.5 mm radial section.", "applications": [ "ventilation and extraction fans", "garden and groundcare equipment", "small packaging and labelling machines" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 25 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 19.8 mm s1 dimension is the screw seating geometry inside the 19.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 25 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-205-2RFGR-HV?", "a": "The catalogue envelope is 25x52x34.1 mm with a spherical outside surface; mass 190 g. Ratings C 11.9/7.8 kN, Pu 0.335 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YAR 205-2RFGR/HV mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed." }, { "q": "How do the set screws lock the 25 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-205-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-205", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-100-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-205-100", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-205-2RFGR-HV", "YAR 205-2RFGR/HV" ], "locale_variants": {} }, { "sku": "YARAG-205", "brand": "SKF", "manufacturer_designation": "YARAG 205", "series": "YAR2-series", "type": "insert", "d_mm": 25, "D_mm": 52, "B_mm": 34.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 1500, "max_rpm": 1500, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YARAG 205 is a grub-screw insert bearing with the inner ring extended on both sides, 25x52x34.1 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 25x52x34.1 mm (0.984x2.047x1.343 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,500 r/min; mass 190 g. Bore-to-OD planning: OD 52 over bore 25 is a 2.08x step, while bore/overall-width gives 0.733; the spherical seat in the matching Y-housing must be specified to the 52 mm OD, not to a cylindrical housing bore. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 25x52 mm insert on its chamfer tilts the whole spherical seat. Selection figures for YARAG 205: C0/C is 0.557, Pu 0.335 kN is 2.393 % of the 14 kN dynamic rating, and the 190 g catalogue mass works out to roughly 7.6 g per millimetre of the 25 mm bore. Pitch-diameter arithmetic: dm = (25+52)/2 = 38.5 mm; at the 1,500 r/min limiting speed the ball set runs at dn approx 0.58x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Static-first planning: the 0.229 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 25 mm shaft, not the 14 kN L10 value. Set-screw geometry on this size: the two 120 deg screws bear on the 25 mm shaft inside the 34.1 mm total width while the outer ring is only 15 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "head- and tail-shaft pillow blocks in unit handling", "trough conveyor idler drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The 19.8 mm s1 dimension is the screw seating geometry inside the 19.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 25 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 14/7.8 kN figures belong specifically to YARAG 205; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-205?", "a": "The catalogue envelope is 25x52x34.1 mm with a spherical outside surface; mass 190 g. Ratings C 14/7.8 kN, Pu 0.335 kN, limiting speed 1,500 r/min." }, { "q": "What does the designation YARAG 205 mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "How is YARAG-205 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 25 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-205-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-100-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 205-100 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-205", "YARAG 205" ], "locale_variants": {} }, { "sku": "YAR-205-2RF", "brand": "SKF", "manufacturer_designation": "YAR 205-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 25, "D_mm": 52, "B_mm": 34.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 205-2RF is a grub-screw insert bearing with the inner ring extended on both sides, 25x52x34.1 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2RF external design combines contact nitrile seals with rubberized additional flingers on both sides for a tighter labyrinth than the plain-flinger -2F execution. Envelope 25x52x34.1 mm (0.984x2.047x1.343 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 190 g. Speed ceiling of 4,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. At the printed limiting speed of 4,300 r/min the mean diameter dm = 38.5 mm implies dn about 1.66x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Capacity density: 14 kN from 0.190 kg of bearing steel is about 73.684 kN per kilogram, and per width millimetre the 34.1 mm unit carries 0.411 kN of dynamic capacity. Static-first planning: the 0.229 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 25 mm shaft, not the 14 kN L10 value. Rating split for the maintenance file: dynamic 14 kN (L10), static 7.8 kN (s0 shock check), fatigue 0.335 kN (adjusted life) — three separate uses for YAR 205-2RF, none interchangeable with another. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Set-screw geometry on this size: the two 120 deg screws bear on the 25 mm shaft inside the 34.1 mm total width while the outer ring is only 15 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small packaging and labelling machines", "head- and tail-shaft pillow blocks in unit handling", "ventilation and extraction fans" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Do not specify the 25 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 19.8 mm s1 dimension is the screw seating geometry inside the 19.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 205-2RF as the grub two rf execution; other order numbers of the YAR 205 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-205-2RF?", "a": "The catalogue envelope is 25x52x34.1 mm with a spherical outside surface; mass 190 g. Ratings C 14/7.8 kN, Pu 0.335 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YAR 205-2RF mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2RF external design combines contact nitrile seals with rubberized additional flingers on both sides for a tighter labyrinth than the plain-flinger -2F execution." }, { "q": "How is YAR-205-2RF lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 25 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-205-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 205 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-100-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 205-100 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-205-2RF", "YAR 205-2RF" ], "locale_variants": {} }, { "sku": "YAR-205-2RF-VE495", "brand": "SKF", "manufacturer_designation": "YAR 205-2RF/VE495", "series": "YAR2-series", "type": "insert", "d_mm": 25, "D_mm": 52, "B_mm": 34.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 205-2RF/VE495 is a SKF insert bearing (Y-bearing) for a 25 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 52 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the VE495 suffix packages zinc-coated rings with stainless-reinforced food-grade seals/flingers and food-grade lubricant — the wash-down-resistant counterpart of the standard -2RF bearing. Envelope 25x52x34.1 mm (0.984x2.047x1.343 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 190 g. Spherical-seat note in numbers: the 52 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 38.5 = 120.951 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Bore-to-OD planning: OD 52 over bore 25 is a 2.08x step, while bore/overall-width gives 0.733; the spherical seat in the matching Y-housing must be specified to the 52 mm OD, not to a cylindrical housing bore. Rating split for the maintenance file: dynamic 14 kN (L10), static 7.8 kN (s0 shock check), fatigue 0.335 kN (adjusted life) — three separate uses for YAR 205-2RF/VE495, none interchangeable with another. Envelope arithmetic: the radial section from 25 mm bore to 52 mm OD is 13.5 mm; dividing C 14 kN by that section gives 1.037 kN per section millimetre, and the 34.1 mm overall width is 2.526x the section. Load balance for documentation: C0 7.8 kN against C 14 kN gives a 0.557 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Zinc-coated food-range note: the VE495 plating is a functional surface, not cosmetic; clean the bore and shaft WITHOUT steel brushes or aggressive descalers, mount dry or with the approved food-grade mounting paste, and touch up damaged plating spots before commissioning the wash-down area. Set-screw geometry on this size: the two 120 deg screws bear on the 25 mm shaft inside the 34.1 mm total width while the outer ring is only 15 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small packaging and labelling machines", "ventilation and extraction fans", "head- and tail-shaft pillow blocks in unit handling" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 25 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 19.8 mm s1 dimension is the screw seating geometry inside the 19.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 205-2RF/VE495 as the grub two ve495 execution; other order numbers of the YAR 205 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-205-2RF-VE495?", "a": "Boundary dimensions: bore 25 mm, sphered OD 52 mm, overall width 34.1 mm; weight 190 g. Loads: dynamic 14 kN, static 7.8 kN, fatigue 0.335 kN; the only published speed is the 4,300 r/min limiting value." }, { "q": "What does the designation YAR 205-2RF/VE495 mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the VE495 suffix packages zinc-coated rings with stainless-reinforced food-grade seals/flingers and food-grade lubricant — the wash-down-resistant counterpart of the standard -2RF bearing." }, { "q": "How do the set screws lock the 25 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-205-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 205 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-100-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 205-100 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-205-2RF-VE495", "YAR 205-2RF/VE495" ], "locale_variants": {} }, { "sku": "YAR-205-2F", "brand": "SKF", "manufacturer_designation": "YAR 205-2F", "series": "YAR2-series", "type": "insert", "d_mm": 25, "D_mm": 52, "B_mm": 34.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 205-2F is a grub-screw insert bearing with the inner ring extended on both sides, 25x52x34.1 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 25x52x34.1 mm (0.984x2.047x1.343 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 7,000 r/min; mass 190 g. Outer-vs-overall width: the outer ring is 15 mm wide inside the 34.1 mm total, so the extended inner ring accounts for 0.56 of the overall width (9.55 mm of axial projection per side). At the printed limiting speed of 7,000 r/min the mean diameter dm = 38.5 mm implies dn about 2.69x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Selection figures for YAR 205-2F: C0/C is 0.557, Pu 0.335 kN is 2.393 % of the 14 kN dynamic rating, and the 190 g catalogue mass works out to roughly 7.6 g per millimetre of the 25 mm bore. Spherical-seat note in numbers: the 52 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 38.5 = 120.951 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 33.7 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 25 mm shaft inside the 34.1 mm total width while the outer ring is only 15 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "head- and tail-shaft pillow blocks in unit handling", "garden and groundcare equipment" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Do not specify the 25 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 19.8 mm s1 dimension is the screw seating geometry inside the 19.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 205-2F as the grub two f execution; other order numbers of the YAR 205 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-205-2F?", "a": "The catalogue envelope is 25x52x34.1 mm with a spherical outside surface; mass 190 g. Ratings C 14/7.8 kN, Pu 0.335 kN, limiting speed 7,000 r/min." }, { "q": "What does the designation YAR 205-2F mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "How is YAR-205-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 25 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-205-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 205 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-100-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 205-100 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-205-2F", "YAR 205-2F" ], "locale_variants": {} }, { "sku": "YAT-206", "brand": "SKF", "manufacturer_designation": "YAT 206", "series": "YAR2-series", "type": "insert", "d_mm": 30, "D_mm": 62, "B_mm": 30.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 260, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAT 206 is SKF's 30 mm-bore grub-screw insert bearing with the inner ring extended on one side in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 30x62x30.2 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAT prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring is extended on one side only. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. this suffix-free execution is listed without the sealed external design: the 30.2 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals. Envelope 30x62x30.2 mm (1.181x2.441x1.189 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 260 g. Envelope arithmetic: the radial section from 30 mm bore to 62 mm OD is 16 mm; dividing C 19.5 kN by that section gives 1.219 kN per section millimetre, and the 30.2 mm overall width is 1.887x the section. Speed ceiling of 6,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Bore-to-OD planning: OD 62 over bore 30 is a 2.067x step, while bore/overall-width gives 0.993; the spherical seat in the matching Y-housing must be specified to the 62 mm OD, not to a cylindrical housing bore. Pitch-diameter arithmetic: dm = (30+62)/2 = 46 mm; at the 6,300 r/min limiting speed the ball set runs at dn approx 2.90x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. At the printed limiting speed of 6,300 r/min the mean diameter dm = 46 mm implies dn about 2.90x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Service tip for YAT-206: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 16 mm radial section.", "applications": [ "ventilation and extraction fans", "head- and tail-shaft pillow blocks in unit handling", "small packaging and labelling machines" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 30 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 21 mm s1 dimension is the screw seating geometry inside the 12.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAT 206 as the grub one open execution; other order numbers of the YAT 206 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-206?", "a": "YAT 206 measures 30 mm bore x 62 mm OD x 30.2 mm overall width (outer ring 18 mm wide), 1.181 x 2.441 x 1.189 in; mass about 260 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YAT 206 mean?", "a": "the YAT prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring is extended on one side only. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. this suffix-free execution is listed without the sealed external design: the 30.2 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals." }, { "q": "How is YAT-206 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 30 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAT-206-103", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x30.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAT 206-103 is the grub-screw locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-206", "YAT 206" ], "locale_variants": {} }, { "sku": "YAR-206-2RF-HV", "brand": "SKF", "manufacturer_designation": "YAR 206-2RF/HV", "series": "YAR2-series", "type": "insert", "d_mm": 30, "D_mm": 62, "B_mm": 38.1, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 16.3, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 206-2RF/HV is a SKF insert bearing (Y-bearing) for a 30 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 62 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part. Envelope 30x62x38.1 mm (1.181x2.441x1.5 in), outer ring 18 mm wide, C 16.3 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,800 r/min; mass 300 g. Spherical-seat note in numbers: the 62 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 46 = 144.513 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Width accounting on this execution: 38.1 mm overall and 18 mm outer-ring width leave the housing designer 20.1 mm of inner-ring projection to accommodate the locking arrangement. Static-first planning: the 0.294 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 30 mm shaft, not the 16.3 kN L10 value. Mass-to-load ratio for YAR-206-2RF-HV: 18.405 g of catalogue mass per rated kN of C, and 10 g per millimetre of bore — useful when comparing executions of the same 30x62 mm envelope on the drawing. At the printed limiting speed of 3,800 r/min the mean diameter dm = 46 mm implies dn about 1.75x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-206-2RF-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 16 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "small packaging and labelling machines", "garden and groundcare equipment" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 30 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 16.3/11.2 kN figures belong specifically to YAR 206-2RF/HV; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-206-2RF-HV?", "a": "Boundary dimensions: bore 30 mm, sphered OD 62 mm, overall width 38.1 mm; weight 300 g. Loads: dynamic 16.3 kN, static 11.2 kN, fatigue 0.475 kN; the only published speed is the 3,800 r/min limiting value." }, { "q": "What does the designation YAR 206-2RF/HV mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR-206-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-206", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-103-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-206-103", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-206-2RF-HV", "YAR 206-2RF/HV" ], "locale_variants": {} }, { "sku": "YAR-206-2RFGR-HV", "brand": "SKF", "manufacturer_designation": "YAR 206-2RFGR/HV", "series": "YAR2-series", "type": "insert", "d_mm": 30, "D_mm": 62, "B_mm": 38.1, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 16.3, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 206-2RFGR/HV is a SKF insert bearing (Y-bearing) for a 30 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 62 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the HV suffix means stainless rings and balls with food-grade compliant seals and grease (this article also carries the GR outside-surface lubrication groove); capacity is derated versus the carbon-steel part. Envelope 30x62x38.1 mm (1.181x2.441x1.5 in), outer ring 18 mm wide, C 16.3 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,800 r/min; mass 300 g. Capacity density: 16.3 kN from 0.300 kg of bearing steel is about 54.333 kN per kilogram, and per width millimetre the 38.1 mm unit carries 0.428 kN of dynamic capacity. Imperial procurement cross-check: 1.181 in bore, 2.441 in OD, 1.5 in overall width; the 300 g mass converts to 0.300 kg (10.6 oz) for the bill of materials. Load balance for documentation: C0 11.2 kN against C 16.3 kN gives a 0.687 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Spherical-seat note in numbers: the 62 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 46 = 144.513 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fatigue-limit check: Pu 0.475 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAR 206-2RFGR/HV — most belt-driven mounted-unit loads sit comfortably under 2.914 % of C. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-206-2RFGR-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 16 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "small packaging and labelling machines", "garden and groundcare equipment" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Do not specify the 30 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAR 206-2RFGR/HV as the grub two hv execution; other order numbers of the YAR 206 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-206-2RFGR-HV?", "a": "Boundary dimensions: bore 30 mm, sphered OD 62 mm, overall width 38.1 mm; weight 300 g. Loads: dynamic 16.3 kN, static 11.2 kN, fatigue 0.475 kN; the only published speed is the 3,800 r/min limiting value." }, { "q": "What does the designation YAR 206-2RFGR/HV mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the HV suffix means stainless rings and balls with food-grade compliant seals and grease (this article also carries the GR outside-surface lubrication groove); capacity is derated versus the carbon-steel part." }, { "q": "How is YAR-206-2RFGR-HV lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 30 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-206-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-206", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-103-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-206-103", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-206-2RFGR-HV", "YAR 206-2RFGR/HV" ], "locale_variants": {} }, { "sku": "YARAG-206", "brand": "SKF", "manufacturer_designation": "YARAG 206", "series": "YAR2-series", "type": "insert", "d_mm": 30, "D_mm": 62, "B_mm": 38.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 1200, "max_rpm": 1200, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YARAG 206 is a SKF insert bearing (Y-bearing) for a 30 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 62 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution. Envelope 30x62x38.1 mm (1.181x2.441x1.5 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,200 r/min; mass 300 g. Spherical-seat note in numbers: the 62 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 46 = 144.513 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Outer-vs-overall width: the outer ring is 18 mm wide inside the 38.1 mm total, so the extended inner ring accounts for 0.528 of the overall width (10.05 mm of axial projection per side). Static-first planning: the 0.294 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 30 mm shaft, not the 19.5 kN L10 value. Envelope arithmetic: the radial section from 30 mm bore to 62 mm OD is 16 mm; dividing C 19.5 kN by that section gives 1.219 kN per section millimetre, and the 38.1 mm overall width is 2.381x the section. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 39.7 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Service tip for YARAG-206: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 16 mm radial section.", "applications": [ "small packaging and labelling machines", "garden and groundcare equipment", "head- and tail-shaft pillow blocks in unit handling" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 30 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 19.5/11.2 kN figures belong specifically to YARAG 206; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-206?", "a": "Boundary dimensions: bore 30 mm, sphered OD 62 mm, overall width 38.1 mm; weight 300 g. Loads: dynamic 19.5 kN, static 11.2 kN, fatigue 0.475 kN; the only published speed is the 1,200 r/min limiting value." }, { "q": "What does the designation YARAG 206 mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-206-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-103-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-206-103", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 206-103 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-206", "YARAG 206" ], "locale_variants": {} }, { "sku": "YAR-206-2RF", "brand": "SKF", "manufacturer_designation": "YAR 206-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 30, "D_mm": 62, "B_mm": 38.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 310, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 206-2RF is a grub-screw insert bearing with the inner ring extended on both sides, 30x62x38.1 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2RF external design combines contact nitrile seals with rubberized additional flingers on both sides for a tighter labyrinth than the plain-flinger -2F execution. Envelope 30x62x38.1 mm (1.181x2.441x1.5 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,800 r/min; mass 310 g. Bore-to-OD planning: OD 62 over bore 30 is a 2.067x step, while bore/overall-width gives 0.787; the spherical seat in the matching Y-housing must be specified to the 62 mm OD, not to a cylindrical housing bore. Spherical-seat note in numbers: the 62 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 46 = 144.513 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. At the printed limiting speed of 3,800 r/min the mean diameter dm = 46 mm implies dn about 1.75x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Mass-to-load ratio for YAR-206-2RF: 15.897 g of catalogue mass per rated kN of C, and 10.333 g per millimetre of bore — useful when comparing executions of the same 30x62 mm envelope on the drawing. Pitch-diameter arithmetic: dm = (30+62)/2 = 46 mm; at the 3,800 r/min limiting speed the ball set runs at dn approx 1.75x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Set-screw geometry on this size: the two 120 deg screws bear on the 30 mm shaft inside the 38.1 mm total width while the outer ring is only 18 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "trough conveyor idler drives", "garden and groundcare equipment" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 30 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 19.5/11.2 kN figures belong specifically to YAR 206-2RF; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-206-2RF?", "a": "The catalogue envelope is 30x62x38.1 mm with a spherical outside surface; mass 310 g. Ratings C 19.5/11.2 kN, Pu 0.475 kN, limiting speed 3,800 r/min." }, { "q": "What does the designation YAR 206-2RF mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2RF external design combines contact nitrile seals with rubberized additional flingers on both sides for a tighter labyrinth than the plain-flinger -2F execution." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-206-2RF lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-206-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-206", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 206 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-103-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-206-103", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 206-103 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-206-2RF", "YAR 206-2RF" ], "locale_variants": {} }, { "sku": "YAR-206-2RF-VE495", "brand": "SKF", "manufacturer_designation": "YAR 206-2RF/VE495", "series": "YAR2-series", "type": "insert", "d_mm": 30, "D_mm": 62, "B_mm": 38.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 310, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 206-2RF/VE495 is a SKF insert bearing (Y-bearing) for a 30 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 62 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the VE495 suffix packages zinc-coated rings with stainless-reinforced food-grade seals/flingers and food-grade lubricant — the wash-down-resistant counterpart of the standard -2RF bearing. Envelope 30x62x38.1 mm (1.181x2.441x1.5 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,800 r/min; mass 310 g. Speed ceiling of 3,800 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Grease-life arithmetic is dominated by speed: at dn approx 1.75x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Width accounting on this execution: 38.1 mm overall and 18 mm outer-ring width leave the housing designer 20.1 mm of inner-ring projection to accommodate the locking arrangement. Static-first planning: the 0.294 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 30 mm shaft, not the 19.5 kN L10 value. At the printed limiting speed of 3,800 r/min the mean diameter dm = 46 mm implies dn about 1.75x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Zinc-coated food-range note: the VE495 plating is a functional surface, not cosmetic; clean the bore and shaft WITHOUT steel brushes or aggressive descalers, mount dry or with the approved food-grade mounting paste, and touch up damaged plating spots before commissioning the wash-down area. Set-screw geometry on this size: the two 120 deg screws bear on the 30 mm shaft inside the 38.1 mm total width while the outer ring is only 18 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small packaging and labelling machines", "garden and groundcare equipment", "ventilation and extraction fans" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 30 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 30 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-206-2RF-VE495?", "a": "Boundary dimensions: bore 30 mm, sphered OD 62 mm, overall width 38.1 mm; weight 310 g. Loads: dynamic 19.5 kN, static 11.2 kN, fatigue 0.475 kN; the only published speed is the 3,800 r/min limiting value." }, { "q": "What does the designation YAR 206-2RF/VE495 mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the VE495 suffix packages zinc-coated rings with stainless-reinforced food-grade seals/flingers and food-grade lubricant — the wash-down-resistant counterpart of the standard -2RF bearing." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-206-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-206", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 206 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-103-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-206-103", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 206-103 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-206-2RF-VE495", "YAR 206-2RF/VE495" ], "locale_variants": {} }, { "sku": "YAR-206-2F", "brand": "SKF", "manufacturer_designation": "YAR 206-2F", "series": "YAR2-series", "type": "insert", "d_mm": 30, "D_mm": 62, "B_mm": 38.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 310, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 206-2F is a SKF insert bearing (Y-bearing) for a 30 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 62 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 30x62x38.1 mm (1.181x2.441x1.5 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 310 g. Speed ceiling of 6,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Load balance for documentation: C0 11.2 kN against C 19.5 kN gives a 0.574 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Imperial procurement cross-check: 1.181 in bore, 2.441 in OD, 1.5 in overall width; the 310 g mass converts to 0.310 kg (10.9 oz) for the bill of materials. Spherical-seat note in numbers: the 62 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 46 = 144.513 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. The s1 22.2 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-206-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 16 mm radial section.", "applications": [ "ventilation and extraction fans", "garden and groundcare equipment", "small packaging and labelling machines" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 30 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Ordering discipline for the 30 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-206-2F?", "a": "Boundary dimensions: bore 30 mm, sphered OD 62 mm, overall width 38.1 mm; weight 310 g. Loads: dynamic 19.5 kN, static 11.2 kN, fatigue 0.475 kN; the only published speed is the 6,300 r/min limiting value." }, { "q": "What does the designation YAR 206-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-206-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-206", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 206 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-103-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-206-103", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 206-103 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-206-2F", "YAR 206-2F" ], "locale_variants": {} }, { "sku": "YAT-207", "brand": "SKF", "manufacturer_designation": "YAT 207", "series": "YAR2-series", "type": "insert", "d_mm": 35, "D_mm": 72, "B_mm": 33, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 380, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAT 207 is a SKF insert bearing (Y-bearing) for a 35 mm shaft: grub-screw insert bearing with the inner ring extended on one side, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings. Envelope 35x72x33 mm (1.378x2.835x1.299 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 380 g. Fatigue-limit check: Pu 0.655 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAT 207 — most belt-driven mounted-unit loads sit comfortably under 2.569 % of C. Spherical-seat note in numbers: the 72 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 53.5 = 168.075 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Mass-to-load ratio for YAT-207: 14.902 g of catalogue mass per rated kN of C, and 10.857 g per millimetre of bore — useful when comparing executions of the same 35x72 mm envelope on the drawing. Static-first planning: the 0.464 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 35 mm shaft, not the 25.5 kN L10 value. Load balance for documentation: C0 15.3 kN against C 25.5 kN gives a 0.6 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Service tip for YAT-207: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 18.5 mm radial section.", "applications": [ "small packaging and labelling machines", "trough conveyor idler drives", "head- and tail-shaft pillow blocks in unit handling" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Do not specify the 35 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 23.3 mm s1 dimension is the screw seating geometry inside the 14 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAT 207 as the grub one open execution; other order numbers of the YAT 207 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-207?", "a": "Boundary dimensions: bore 35 mm, sphered OD 72 mm, overall width 33 mm; weight 380 g. Loads: dynamic 25.5 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 5,300 r/min limiting value." }, { "q": "What does the designation YAT 207 mean?", "a": "reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAT-207 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-207", "YAT 207" ], "locale_variants": {} }, { "sku": "YAR-207-2RF-HV", "brand": "SKF", "manufacturer_designation": "YAR 207-2RF/HV", "series": "YAR2-series", "type": "insert", "d_mm": 35, "D_mm": 72, "B_mm": 42.9, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 21.6, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 207-2RF/HV is a grub-screw insert bearing with the inner ring extended on both sides, 35x72x42.9 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed. Envelope 35x72x42.9 mm (1.378x2.835x1.689 in), outer ring 19 mm wide, C 21.6 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,200 r/min; mass 450 g. Width accounting on this execution: 42.9 mm overall and 19 mm outer-ring width leave the housing designer 23.9 mm of inner-ring projection to accommodate the locking arrangement. Pitch-diameter arithmetic: dm = (35+72)/2 = 53.5 mm; at the 3,200 r/min limiting speed the ball set runs at dn approx 1.71x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Bore-to-OD planning: OD 72 over bore 35 is a 2.057x step, while bore/overall-width gives 0.816; the spherical seat in the matching Y-housing must be specified to the 72 mm OD, not to a cylindrical housing bore. Imperial procurement cross-check: 1.378 in bore, 2.835 in OD, 1.689 in overall width; the 450 g mass converts to 0.450 kg (15.9 oz) for the bill of materials. Load balance for documentation: C0 15.3 kN against C 21.6 kN gives a 0.708 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-207-2RF-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 18.5 mm radial section.", "applications": [ "trough conveyor idler drives", "head- and tail-shaft pillow blocks in unit handling", "ventilation and extraction fans" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 35 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 21.6/15.3 kN figures belong specifically to YAR 207-2RF/HV; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-2RF-HV?", "a": "The catalogue envelope is 35x72x42.9 mm with a spherical outside surface; mass 450 g. Ratings C 21.6/15.3 kN, Pu 0.655 kN, limiting speed 3,200 r/min." }, { "q": "What does the designation YAR 207-2RF/HV mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-207-2RF-HV lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-207-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-207", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-106-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-207-106", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-2RF-HV", "YAR 207-2RF/HV" ], "locale_variants": {} }, { "sku": "YAR-207-2RFGR-HV", "brand": "SKF", "manufacturer_designation": "YAR 207-2RFGR/HV", "series": "YAR2-series", "type": "insert", "d_mm": 35, "D_mm": 72, "B_mm": 42.9, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 21.6, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 207-2RFGR/HV is SKF's 35 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 35x72x42.9 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. /HV identifies the stainless-steel, food-industry execution: stainless bearing components, food-compatible rubber in the seal/flinger set and food-grade grease fill — the catalogue ratings are correspondingly below the standard steel version, and the GR marking adds the lubrication groove in the sphered outside surface on the locking side. Envelope 35x72x42.9 mm (1.378x2.835x1.689 in), outer ring 19 mm wide, C 21.6 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,200 r/min; mass 450 g. Static-first planning: the 0.357 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 35 mm shaft, not the 21.6 kN L10 value. Grease-life arithmetic is dominated by speed: at dn approx 1.71x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Pitch-diameter arithmetic: dm = (35+72)/2 = 53.5 mm; at the 3,200 r/min limiting speed the ball set runs at dn approx 1.71x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Bore-to-OD planning: OD 72 over bore 35 is a 2.057x step, while bore/overall-width gives 0.816; the spherical seat in the matching Y-housing must be specified to the 72 mm OD, not to a cylindrical housing bore. Selection figures for YAR 207-2RFGR/HV: C0/C is 0.708, Pu 0.655 kN is 3.032 % of the 21.6 kN dynamic rating, and the 450 g catalogue mass works out to roughly 12.857 g per millimetre of the 35 mm bore. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-207-2RFGR-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 18.5 mm radial section.", "applications": [ "garden and groundcare equipment", "head- and tail-shaft pillow blocks in unit handling", "trough conveyor idler drives" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 35 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 35 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-2RFGR-HV?", "a": "YAR 207-2RFGR/HV measures 35 mm bore x 72 mm OD x 42.9 mm overall width (outer ring 19 mm wide), 1.378 x 2.835 x 1.689 in; mass about 450 g. SKF 17000 ratings: C 21.6 kN, C0 15.3 kN, Pu 0.655 kN, limiting speed 3,200 r/min." }, { "q": "What does the designation YAR 207-2RFGR/HV mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. /HV identifies the stainless-steel, food-industry execution: stainless bearing components, food-compatible rubber in the seal/flinger set and food-grade grease fill — the catalogue ratings are correspondingly below the standard steel version, and the GR marking adds the lubrication groove in the sphered outside surface on the locking side." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-207-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-207", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-106-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-207-106", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-2RFGR-HV", "YAR 207-2RFGR/HV" ], "locale_variants": {} }, { "sku": "YARAG-207", "brand": "SKF", "manufacturer_designation": "YARAG 207", "series": "YAR2-series", "type": "insert", "d_mm": 35, "D_mm": 72, "B_mm": 42.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YARAG 207 is a grub-screw insert bearing with the inner ring extended on both sides, 35x72x42.9 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 35x72x42.9 mm (1.378x2.835x1.689 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,100 r/min; mass 440 g. Fatigue-limit check: Pu 0.655 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YARAG 207 — most belt-driven mounted-unit loads sit comfortably under 2.569 % of C. Static-first planning: the 0.357 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 35 mm shaft, not the 25.5 kN L10 value. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 35x72 mm insert on its chamfer tilts the whole spherical seat. Imperial procurement cross-check: 1.378 in bore, 2.835 in OD, 1.689 in overall width; the 440 g mass converts to 0.440 kg (15.5 oz) for the bill of materials. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 46.1 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Service tip for YARAG-207: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 18.5 mm radial section.", "applications": [ "small packaging and labelling machines", "head- and tail-shaft pillow blocks in unit handling", "garden and groundcare equipment" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Do not specify the 35 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YARAG 207 as the grub two ag execution; other order numbers of the YARAG 207 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-207?", "a": "The catalogue envelope is 35x72x42.9 mm with a spherical outside surface; mass 440 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 1,100 r/min." }, { "q": "What does the designation YARAG 207 mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR-207-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-106-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-207-106", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207-106 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-207", "YARAG 207" ], "locale_variants": {} }, { "sku": "YAR-207-2RF", "brand": "SKF", "manufacturer_designation": "YAR 207-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 35, "D_mm": 72, "B_mm": 42.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 207-2RF is a SKF insert bearing (Y-bearing) for a 35 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments. Envelope 35x72x42.9 mm (1.378x2.835x1.689 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,200 r/min; mass 450 g. Pitch-diameter arithmetic: dm = (35+72)/2 = 53.5 mm; at the 3,200 r/min limiting speed the ball set runs at dn approx 1.71x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Selection figures for YAR 207-2RF: C0/C is 0.6, Pu 0.655 kN is 2.569 % of the 25.5 kN dynamic rating, and the 450 g catalogue mass works out to roughly 12.857 g per millimetre of the 35 mm bore. Mass-to-load ratio for YAR-207-2RF: 17.647 g of catalogue mass per rated kN of C, and 12.857 g per millimetre of bore — useful when comparing executions of the same 35x72 mm envelope on the drawing. Rating split for the maintenance file: dynamic 25.5 kN (L10), static 15.3 kN (s0 shock check), fatigue 0.655 kN (adjusted life) — three separate uses for YAR 207-2RF, none interchangeable with another. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 35x72 mm insert on its chamfer tilts the whole spherical seat. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Service tip for YAR-207-2RF: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 18.5 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "ventilation and extraction fans", "small packaging and labelling machines" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 35 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Ordering discipline for the 35 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-2RF?", "a": "Boundary dimensions: bore 35 mm, sphered OD 72 mm, overall width 42.9 mm; weight 450 g. Loads: dynamic 25.5 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 3,200 r/min limiting value." }, { "q": "What does the designation YAR 207-2RF mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments." }, { "q": "How do the set screws lock the 35 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-207-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-207", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-106-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-207-106", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207-106 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-2RF", "YAR 207-2RF" ], "locale_variants": {} }, { "sku": "YAR-207-2RF-VE495", "brand": "SKF", "manufacturer_designation": "YAR 207-2RF/VE495", "series": "YAR2-series", "type": "insert", "d_mm": 35, "D_mm": 72, "B_mm": 42.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 207-2RF/VE495 is a SKF insert bearing (Y-bearing) for a 35 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the VE495 suffix packages zinc-coated rings with stainless-reinforced food-grade seals/flingers and food-grade lubricant — the wash-down-resistant counterpart of the standard -2RF bearing. Envelope 35x72x42.9 mm (1.378x2.835x1.689 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,200 r/min; mass 450 g. Capacity density: 25.5 kN from 0.450 kg of bearing steel is about 56.667 kN per kilogram, and per width millimetre the 42.9 mm unit carries 0.594 kN of dynamic capacity. Load balance for documentation: C0 15.3 kN against C 25.5 kN gives a 0.6 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Imperial procurement cross-check: 1.378 in bore, 2.835 in OD, 1.689 in overall width; the 450 g mass converts to 0.450 kg (15.9 oz) for the bill of materials. The s1 25.4 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. At the printed limiting speed of 3,200 r/min the mean diameter dm = 53.5 mm implies dn about 1.71x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Zinc-coated food-range note: the VE495 plating is a functional surface, not cosmetic; clean the bore and shaft WITHOUT steel brushes or aggressive descalers, mount dry or with the approved food-grade mounting paste, and touch up damaged plating spots before commissioning the wash-down area. Service tip for YAR-207-2RF-VE495: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 18.5 mm radial section.", "applications": [ "trough conveyor idler drives", "garden and groundcare equipment", "small packaging and labelling machines" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 35 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 35 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-2RF-VE495?", "a": "Boundary dimensions: bore 35 mm, sphered OD 72 mm, overall width 42.9 mm; weight 450 g. Loads: dynamic 25.5 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 3,200 r/min limiting value." }, { "q": "What does the designation YAR 207-2RF/VE495 mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the VE495 suffix packages zinc-coated rings with stainless-reinforced food-grade seals/flingers and food-grade lubricant — the wash-down-resistant counterpart of the standard -2RF bearing." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-207-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-207", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-106-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-207-106", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207-106 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-2RF-VE495", "YAR 207-2RF/VE495" ], "locale_variants": {} }, { "sku": "YAR-207-2F", "brand": "SKF", "manufacturer_designation": "YAR 207-2F", "series": "YAR2-series", "type": "insert", "d_mm": 35, "D_mm": 72, "B_mm": 42.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 207-2F is a SKF insert bearing (Y-bearing) for a 35 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 35x72x42.9 mm (1.378x2.835x1.689 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 450 g. Grease-life arithmetic is dominated by speed: at dn approx 2.84x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Selection figures for YAR 207-2F: C0/C is 0.6, Pu 0.655 kN is 2.569 % of the 25.5 kN dynamic rating, and the 450 g catalogue mass works out to roughly 12.857 g per millimetre of the 35 mm bore. Speed ceiling of 5,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Imperial procurement cross-check: 1.378 in bore, 2.835 in OD, 1.689 in overall width; the 450 g mass converts to 0.450 kg (15.9 oz) for the bill of materials. Outer-vs-overall width: the outer ring is 19 mm wide inside the 42.9 mm total, so the extended inner ring accounts for 0.557 of the overall width (11.95 mm of axial projection per side). Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 35 mm shaft inside the 42.9 mm total width while the outer ring is only 19 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "trough conveyor idler drives", "ventilation and extraction fans", "garden and groundcare equipment" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 35 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 25.5/15.3 kN figures belong specifically to YAR 207-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-2F?", "a": "Boundary dimensions: bore 35 mm, sphered OD 72 mm, overall width 42.9 mm; weight 450 g. Loads: dynamic 25.5 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 5,300 r/min limiting value." }, { "q": "What does the designation YAR 207-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "How do the set screws lock the 35 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-207-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-207", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-106-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-207-106", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207-106 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-2F", "YAR 207-2F" ], "locale_variants": {} }, { "sku": "YAT-208", "brand": "SKF", "manufacturer_designation": "YAT 208", "series": "YAR2-series", "type": "insert", "d_mm": 40, "D_mm": 80, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAT 208 is a grub-screw insert bearing with the inner ring extended on one side, 40x80x36 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 40x80x36 mm (1.575x3.15x1.417 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,800 r/min; mass 500 g. Fatigue-limit check: Pu 0.8 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAT 208 — most belt-driven mounted-unit loads sit comfortably under 2.606 % of C. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 51.8 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Imperial procurement cross-check: 1.575 in bore, 3.15 in OD, 1.417 in overall width; the 500 g mass converts to 0.500 kg (17.6 oz) for the bill of materials. Grease-life arithmetic is dominated by speed: at dn approx 2.88x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Bore-to-OD planning: OD 80 over bore 40 is a 2x step, while bore/overall-width gives 1.111; the spherical seat in the matching Y-housing must be specified to the 80 mm OD, not to a cylindrical housing bore. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Set-screw geometry on this size: the two 120 deg screws bear on the 40 mm shaft inside the 36 mm total width while the outer ring is only 21 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "trough conveyor idler drives", "small packaging and labelling machines", "head- and tail-shaft pillow blocks in unit handling" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 40 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 25.3 mm s1 dimension is the screw seating geometry inside the 15 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAT 208 as the grub one open execution; other order numbers of the YAT 208 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-208?", "a": "The catalogue envelope is 40x80x36 mm with a spherical outside surface; mass 500 g. Ratings C 30.7/19 kN, Pu 0.8 kN, limiting speed 4,800 r/min." }, { "q": "What does the designation YAT 208 mean?", "a": "YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-208", "YAT 208" ], "locale_variants": {} }, { "sku": "YAR-208-2RF-HV", "brand": "SKF", "manufacturer_designation": "YAR 208-2RF/HV", "series": "YAR2-series", "type": "insert", "d_mm": 40, "D_mm": 80, "B_mm": 49.2, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 24.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 208-2RF/HV is a SKF insert bearing (Y-bearing) for a 40 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 80 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part. Envelope 40x80x49.2 mm (1.575x3.15x1.937 in), outer ring 21 mm wide, C 24.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,800 r/min; mass 600 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 51.8 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Grease-life arithmetic is dominated by speed: at dn approx 1.68x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Imperial procurement cross-check: 1.575 in bore, 3.15 in OD, 1.937 in overall width; the 600 g mass converts to 0.600 kg (21.2 oz) for the bill of materials. Rating split for the maintenance file: dynamic 24.7 kN (L10), static 19 kN (s0 shock check), fatigue 0.8 kN (adjusted life) — three separate uses for YAR 208-2RF/HV, none interchangeable with another. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 40x80 mm insert on its chamfer tilts the whole spherical seat. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Set-screw geometry on this size: the two 120 deg screws bear on the 40 mm shaft inside the 49.2 mm total width while the outer ring is only 21 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "trough conveyor idler drives", "garden and groundcare equipment", "small packaging and labelling machines" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 40 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 30.2 mm s1 dimension is the screw seating geometry inside the 28.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 40 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-208-2RF-HV?", "a": "Boundary dimensions: bore 40 mm, sphered OD 80 mm, overall width 49.2 mm; weight 600 g. Loads: dynamic 24.7 kN, static 19 kN, fatigue 0.8 kN; the only published speed is the 2,800 r/min limiting value." }, { "q": "What does the designation YAR 208-2RF/HV mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-208-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-208", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-109-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 40 mm vs 39.6875 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-208-2RF-HV", "YAR 208-2RF/HV" ], "locale_variants": {} }, { "sku": "YAR-208-2RFGR-HV", "brand": "SKF", "manufacturer_designation": "YAR 208-2RFGR/HV", "series": "YAR2-series", "type": "insert", "d_mm": 40, "D_mm": 80, "B_mm": 49.2, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 24.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 208-2RFGR/HV is a SKF insert bearing (Y-bearing) for a 40 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 80 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the HV suffix means stainless rings and balls with food-grade compliant seals and grease (this article also carries the GR outside-surface lubrication groove); capacity is derated versus the carbon-steel part. Envelope 40x80x49.2 mm (1.575x3.15x1.937 in), outer ring 21 mm wide, C 24.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,800 r/min; mass 600 g. Static-first planning: the 0.386 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 40 mm shaft, not the 24.7 kN L10 value. Mass-to-load ratio for YAR-208-2RFGR-HV: 24.291 g of catalogue mass per rated kN of C, and 15 g per millimetre of bore — useful when comparing executions of the same 40x80 mm envelope on the drawing. At the printed limiting speed of 2,800 r/min the mean diameter dm = 60 mm implies dn about 1.68x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Pitch-diameter arithmetic: dm = (40+80)/2 = 60 mm; at the 2,800 r/min limiting speed the ball set runs at dn approx 1.68x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Spherical-seat note in numbers: the 80 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 60 = 188.496 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Set-screw geometry on this size: the two 120 deg screws bear on the 40 mm shaft inside the 49.2 mm total width while the outer ring is only 21 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "garden and groundcare equipment", "head- and tail-shaft pillow blocks in unit handling" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The 30.2 mm s1 dimension is the screw seating geometry inside the 28.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 40 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 24.7/19 kN figures belong specifically to YAR 208-2RFGR/HV; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-208-2RFGR-HV?", "a": "Boundary dimensions: bore 40 mm, sphered OD 80 mm, overall width 49.2 mm; weight 600 g. Loads: dynamic 24.7 kN, static 19 kN, fatigue 0.8 kN; the only published speed is the 2,800 r/min limiting value." }, { "q": "What does the designation YAR 208-2RFGR/HV mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the HV suffix means stainless rings and balls with food-grade compliant seals and grease (this article also carries the GR outside-surface lubrication groove); capacity is derated versus the carbon-steel part." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-208-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-208", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-109-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 40 mm vs 39.6875 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-208-2RFGR-HV", "YAR 208-2RFGR/HV" ], "locale_variants": {} }, { "sku": "YARAG-208", "brand": "SKF", "manufacturer_designation": "YARAG 208", "series": "YAR2-series", "type": "insert", "d_mm": 40, "D_mm": 80, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 950, "max_rpm": 950, "weight_g": 590, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YARAG 208 is a SKF insert bearing (Y-bearing) for a 40 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 80 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution. Envelope 40x80x49.2 mm (1.575x3.15x1.937 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 950 r/min; mass 590 g. Rating split for the maintenance file: dynamic 30.7 kN (L10), static 19 kN (s0 shock check), fatigue 0.8 kN (adjusted life) — three separate uses for YARAG 208, none interchangeable with another. Fatigue-limit check: Pu 0.8 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YARAG 208 — most belt-driven mounted-unit loads sit comfortably under 2.606 % of C. Load balance for documentation: C0 19 kN against C 30.7 kN gives a 0.619 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Grease-life arithmetic is dominated by speed: at dn approx 0.57x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the AG variant caps speed so aggressively, and high-temperature mounts shorten both even when load is light. Bore-to-OD planning: OD 80 over bore 40 is a 2x step, while bore/overall-width gives 0.813; the spherical seat in the matching Y-housing must be specified to the 80 mm OD, not to a cylindrical housing bore. Set-screw geometry on this size: the two 120 deg screws bear on the 40 mm shaft inside the 49.2 mm total width while the outer ring is only 21 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "small packaging and labelling machines", "trough conveyor idler drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The 30.2 mm s1 dimension is the screw seating geometry inside the 28.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 40 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 30.7/19 kN figures belong specifically to YARAG 208; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-208?", "a": "Boundary dimensions: bore 40 mm, sphered OD 80 mm, overall width 49.2 mm; weight 590 g. Loads: dynamic 30.7 kN, static 19 kN, fatigue 0.8 kN; the only published speed is the 950 r/min limiting value." }, { "q": "What does the designation YARAG 208 mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR-208-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-109-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-109-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 40 mm vs 39.6875 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-208", "YARAG 208" ], "locale_variants": {} }, { "sku": "YAR-208-2RF", "brand": "SKF", "manufacturer_designation": "YAR 208-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 40, "D_mm": 80, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 208-2RF is a grub-screw insert bearing with the inner ring extended on both sides, 40x80x49.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2RF external design combines contact nitrile seals with rubberized additional flingers on both sides for a tighter labyrinth than the plain-flinger -2F execution. Envelope 40x80x49.2 mm (1.575x3.15x1.937 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,800 r/min; mass 600 g. Width accounting on this execution: 49.2 mm overall and 21 mm outer-ring width leave the housing designer 28.2 mm of inner-ring projection to accommodate the locking arrangement. Mass-to-load ratio for YAR-208-2RF: 19.544 g of catalogue mass per rated kN of C, and 15 g per millimetre of bore — useful when comparing executions of the same 40x80 mm envelope on the drawing. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 40x80 mm insert on its chamfer tilts the whole spherical seat. Spherical-seat note in numbers: the 80 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 60 = 188.496 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Pitch-diameter arithmetic: dm = (40+80)/2 = 60 mm; at the 2,800 r/min limiting speed the ball set runs at dn approx 1.68x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Service tip for YAR-208-2RF: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20 mm radial section.", "applications": [ "ventilation and extraction fans", "garden and groundcare equipment", "head- and tail-shaft pillow blocks in unit handling" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The 30.2 mm s1 dimension is the screw seating geometry inside the 28.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 40 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 30.7/19 kN figures belong specifically to YAR 208-2RF; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-208-2RF?", "a": "The catalogue envelope is 40x80x49.2 mm with a spherical outside surface; mass 600 g. Ratings C 30.7/19 kN, Pu 0.8 kN, limiting speed 2,800 r/min." }, { "q": "What does the designation YAR 208-2RF mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2RF external design combines contact nitrile seals with rubberized additional flingers on both sides for a tighter labyrinth than the plain-flinger -2F execution." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-208-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-208", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 208 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-109-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-109-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 40 mm vs 39.6875 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-208-2RF", "YAR 208-2RF" ], "locale_variants": {} }, { "sku": "YAR-208-2RF-VE495", "brand": "SKF", "manufacturer_designation": "YAR 208-2RF/VE495", "series": "YAR2-series", "type": "insert", "d_mm": 40, "D_mm": 80, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 610, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 208-2RF/VE495 is a SKF insert bearing (Y-bearing) for a 40 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 80 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the VE495 suffix packages zinc-coated rings with stainless-reinforced food-grade seals/flingers and food-grade lubricant — the wash-down-resistant counterpart of the standard -2RF bearing. Envelope 40x80x49.2 mm (1.575x3.15x1.937 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,800 r/min; mass 610 g. Capacity density: 30.7 kN from 0.610 kg of bearing steel is about 50.328 kN per kilogram, and per width millimetre the 49.2 mm unit carries 0.624 kN of dynamic capacity. Outer-vs-overall width: the outer ring is 21 mm wide inside the 49.2 mm total, so the extended inner ring accounts for 0.573 of the overall width (14.1 mm of axial projection per side). Fatigue-limit check: Pu 0.8 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAR 208-2RF/VE495 — most belt-driven mounted-unit loads sit comfortably under 2.606 % of C. Static-first planning: the 0.386 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 40 mm shaft, not the 30.7 kN L10 value. Grease-life arithmetic is dominated by speed: at dn approx 1.68x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Zinc-coated food-range note: the VE495 plating is a functional surface, not cosmetic; clean the bore and shaft WITHOUT steel brushes or aggressive descalers, mount dry or with the approved food-grade mounting paste, and touch up damaged plating spots before commissioning the wash-down area. Set-screw geometry on this size: the two 120 deg screws bear on the 40 mm shaft inside the 49.2 mm total width while the outer ring is only 21 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small packaging and labelling machines", "garden and groundcare equipment", "head- and tail-shaft pillow blocks in unit handling" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 40 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 30.2 mm s1 dimension is the screw seating geometry inside the 28.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 40 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-208-2RF-VE495?", "a": "Boundary dimensions: bore 40 mm, sphered OD 80 mm, overall width 49.2 mm; weight 610 g. Loads: dynamic 30.7 kN, static 19 kN, fatigue 0.8 kN; the only published speed is the 2,800 r/min limiting value." }, { "q": "What does the designation YAR 208-2RF/VE495 mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the VE495 suffix packages zinc-coated rings with stainless-reinforced food-grade seals/flingers and food-grade lubricant — the wash-down-resistant counterpart of the standard -2RF bearing." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-208-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-208", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 208 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-109-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-109-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 40 mm vs 39.6875 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-208-2RF-VE495", "YAR 208-2RF/VE495" ], "locale_variants": {} }, { "sku": "YAR-208-2F", "brand": "SKF", "manufacturer_designation": "YAR 208-2F", "series": "YAR2-series", "type": "insert", "d_mm": 40, "D_mm": 80, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 208-2F is SKF's 40 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 40x80x49.2 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 40x80x49.2 mm (1.575x3.15x1.937 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,800 r/min; mass 600 g. Fatigue-limit check: Pu 0.8 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAR 208-2F — most belt-driven mounted-unit loads sit comfortably under 2.606 % of C. Envelope arithmetic: the radial section from 40 mm bore to 80 mm OD is 20 mm; dividing C 30.7 kN by that section gives 1.535 kN per section millimetre, and the 49.2 mm overall width is 2.46x the section. The s1 30.2 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Outer-vs-overall width: the outer ring is 21 mm wide inside the 49.2 mm total, so the extended inner ring accounts for 0.573 of the overall width (14.1 mm of axial projection per side). At the printed limiting speed of 4,800 r/min the mean diameter dm = 60 mm implies dn about 2.88x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-208-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20 mm radial section.", "applications": [ "garden and groundcare equipment", "small packaging and labelling machines", "head- and tail-shaft pillow blocks in unit handling" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 30.2 mm s1 dimension is the screw seating geometry inside the 28.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 40 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Ordering discipline for the 40 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-208-2F?", "a": "YAR 208-2F measures 40 mm bore x 80 mm OD x 49.2 mm overall width (outer ring 21 mm wide), 1.575 x 3.15 x 1.937 in; mass about 600 g. SKF 17000 ratings: C 30.7 kN, C0 19 kN, Pu 0.8 kN, limiting speed 4,800 r/min." }, { "q": "What does the designation YAR 208-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR-208-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-208", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 208 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-109-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-109-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 40 mm vs 39.6875 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-208-2F", "YAR 208-2F" ], "locale_variants": {} }, { "sku": "YAT-209", "brand": "SKF", "manufacturer_designation": "YAT 209", "series": "YAR2-series", "type": "insert", "d_mm": 45, "D_mm": 85, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 560, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAT 209 is a grub-screw insert bearing with the inner ring extended on one side, 45x85x37 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 45x85x37 mm (1.772x3.346x1.457 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 560 g. Spherical-seat note in numbers: the 85 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 65 = 204.204 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Bore-to-OD planning: OD 85 over bore 45 is a 1.889x step, while bore/overall-width gives 1.216; the spherical seat in the matching Y-housing must be specified to the 85 mm OD, not to a cylindrical housing bore. At the printed limiting speed of 4,300 r/min the mean diameter dm = 65 mm implies dn about 2.79x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 45x85 mm insert on its chamfer tilts the whole spherical seat. Fatigue-limit check: Pu 0.915 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAT 209 — most belt-driven mounted-unit loads sit comfortably under 2.756 % of C. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Set-screw geometry on this size: the two 120 deg screws bear on the 45 mm shaft inside the 37 mm total width while the outer ring is only 22 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "trough conveyor idler drives", "ventilation and extraction fans", "small packaging and labelling machines" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "The 25.8 mm s1 dimension is the screw seating geometry inside the 15 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 45 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 33.2/21.6 kN figures belong specifically to YAT 209; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-209?", "a": "The catalogue envelope is 45x85x37 mm with a spherical outside surface; mass 560 g. Ratings C 33.2/21.6 kN, Pu 0.915 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YAT 209 mean?", "a": "YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "How do the set screws lock the 45 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-209", "YAT 209" ], "locale_variants": {} }, { "sku": "YARAG-209", "brand": "SKF", "manufacturer_designation": "YARAG 209", "series": "YAR2-series", "type": "insert", "d_mm": 45, "D_mm": 85, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 850, "max_rpm": 850, "weight_g": 660, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YARAG 209 is a grub-screw insert bearing with the inner ring extended on both sides, 45x85x49.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 45x85x49.2 mm (1.772x3.346x1.937 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 850 r/min; mass 660 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 56.8 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Envelope arithmetic: the radial section from 45 mm bore to 85 mm OD is 20 mm; dividing C 33.2 kN by that section gives 1.66 kN per section millimetre, and the 49.2 mm overall width is 2.46x the section. Static-first planning: the 0.439 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 45 mm shaft, not the 33.2 kN L10 value. Load balance for documentation: C0 21.6 kN against C 33.2 kN gives a 0.651 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 45x85 mm insert on its chamfer tilts the whole spherical seat. Service tip for YARAG-209: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "small packaging and labelling machines", "garden and groundcare equipment" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "The 30.2 mm s1 dimension is the screw seating geometry inside the 27.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 45 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 33.2/21.6 kN figures belong specifically to YARAG 209; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-209?", "a": "The catalogue envelope is 45x85x49.2 mm with a spherical outside surface; mass 660 g. Ratings C 33.2/21.6 kN, Pu 0.915 kN, limiting speed 850 r/min." }, { "q": "What does the designation YARAG 209 mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR-209-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 45x85x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 209-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-209-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 45x85x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 209-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-209", "YARAG 209" ], "locale_variants": {} }, { "sku": "YAR-209-2RF", "brand": "SKF", "manufacturer_designation": "YAR 209-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 45, "D_mm": 85, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 670, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 209-2RF is SKF's 45 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 45x85x49.2 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2RF upgrades the -2F package with a RUBBERIZED flinger on each side — the coated thrower closes the radial gap against fine dust and slurry better than the plain steel flinger of -2F. Envelope 45x85x49.2 mm (1.772x3.346x1.937 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,400 r/min; mass 670 g. Mass-to-load ratio for YAR-209-2RF: 20.181 g of catalogue mass per rated kN of C, and 14.889 g per millimetre of bore — useful when comparing executions of the same 45x85 mm envelope on the drawing. Rating split for the maintenance file: dynamic 33.2 kN (L10), static 21.6 kN (s0 shock check), fatigue 0.915 kN (adjusted life) — three separate uses for YAR 209-2RF, none interchangeable with another. Spherical-seat note in numbers: the 85 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 65 = 204.204 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Capacity density: 33.2 kN from 0.670 kg of bearing steel is about 49.552 kN per kilogram, and per width millimetre the 49.2 mm unit carries 0.675 kN of dynamic capacity. Static-first planning: the 0.439 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 45 mm shaft, not the 33.2 kN L10 value. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Service tip for YAR-209-2RF: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "ventilation and extraction fans", "garden and groundcare equipment" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Do not specify the 45 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 30.2 mm s1 dimension is the screw seating geometry inside the 27.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 209-2RF as the grub two rf execution; other order numbers of the YAR 209 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-209-2RF?", "a": "YAR 209-2RF measures 45 mm bore x 85 mm OD x 49.2 mm overall width (outer ring 22 mm wide), 1.772 x 3.346 x 1.937 in; mass about 670 g. SKF 17000 ratings: C 33.2 kN, C0 21.6 kN, Pu 0.915 kN, limiting speed 2,400 r/min." }, { "q": "What does the designation YAR 209-2RF mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2RF upgrades the -2F package with a RUBBERIZED flinger on each side — the coated thrower closes the radial gap against fine dust and slurry better than the plain steel flinger of -2F." }, { "q": "How do the set screws lock the 45 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YARAG-209", "equiv_brand": "SKF", "level": "full", "note": "Same 45x85x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 209 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-209-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 45x85x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 209-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-209-2RF", "YAR 209-2RF" ], "locale_variants": {} }, { "sku": "YAR-209-2F", "brand": "SKF", "manufacturer_designation": "YAR 209-2F", "series": "YAR2-series", "type": "insert", "d_mm": 45, "D_mm": 85, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 670, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 209-2F is a SKF insert bearing (Y-bearing) for a 45 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 85 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 45x85x49.2 mm (1.772x3.346x1.937 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 670 g. Static-first planning: the 0.439 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 45 mm shaft, not the 33.2 kN L10 value. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 56.8 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Bore-to-OD planning: OD 85 over bore 45 is a 1.889x step, while bore/overall-width gives 0.915; the spherical seat in the matching Y-housing must be specified to the 85 mm OD, not to a cylindrical housing bore. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 45x85 mm insert on its chamfer tilts the whole spherical seat. Capacity density: 33.2 kN from 0.670 kg of bearing steel is about 49.552 kN per kilogram, and per width millimetre the 49.2 mm unit carries 0.675 kN of dynamic capacity. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-209-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20 mm radial section.", "applications": [ "trough conveyor idler drives", "head- and tail-shaft pillow blocks in unit handling", "ventilation and extraction fans" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Do not specify the 45 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 30.2 mm s1 dimension is the screw seating geometry inside the 27.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 209-2F as the grub two f execution; other order numbers of the YAR 209 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-209-2F?", "a": "Boundary dimensions: bore 45 mm, sphered OD 85 mm, overall width 49.2 mm; weight 670 g. Loads: dynamic 33.2 kN, static 21.6 kN, fatigue 0.915 kN; the only published speed is the 4,300 r/min limiting value." }, { "q": "What does the designation YAR 209-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-209-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YARAG-209", "equiv_brand": "SKF", "level": "full", "note": "Same 45x85x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 209 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-209-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 45x85x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 209-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-209-2F", "YAR 209-2F" ], "locale_variants": {} }, { "sku": "YAT-210", "brand": "SKF", "manufacturer_designation": "YAT 210", "series": "YAR2-series", "type": "insert", "d_mm": 50, "D_mm": 90, "B_mm": 38.8, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 630, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAT 210 is a grub-screw insert bearing with the inner ring extended on one side, 50x90x38.8 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 50x90x38.8 mm (1.969x3.543x1.528 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,000 r/min; mass 630 g. Selection figures for YAT 210: C0/C is 0.661, Pu 0.98 kN is 2.792 % of the 35.1 kN dynamic rating, and the 630 g catalogue mass works out to roughly 12.6 g per millimetre of the 50 mm bore. Static-first planning: the 0.598 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 50 mm shaft, not the 35.1 kN L10 value. Load balance for documentation: C0 23.2 kN against C 35.1 kN gives a 0.661 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Rating split for the maintenance file: dynamic 35.1 kN (L10), static 23.2 kN (s0 shock check), fatigue 0.98 kN (adjusted life) — three separate uses for YAT 210, none interchangeable with another. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 50x90 mm insert on its chamfer tilts the whole spherical seat. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Service tip for YAT-210: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "small packaging and labelling machines", "trough conveyor idler drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The 27.6 mm s1 dimension is the screw seating geometry inside the 16.8 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 50 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 35.1/23.2 kN figures belong specifically to YAT 210; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-210?", "a": "The catalogue envelope is 50x90x38.8 mm with a spherical outside surface; mass 630 g. Ratings C 35.1/23.2 kN, Pu 0.98 kN, limiting speed 4,000 r/min." }, { "q": "What does the designation YAT 210 mean?", "a": "YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-210", "YAT 210" ], "locale_variants": {} }, { "sku": "YAR-210-2RF-HV", "brand": "SKF", "manufacturer_designation": "YAR 210-2RF/HV", "series": "YAR2-series", "type": "insert", "d_mm": 50, "D_mm": 90, "B_mm": 51.6, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 29.6, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 760, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 210-2RF/HV is a SKF insert bearing (Y-bearing) for a 50 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 90 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part. Envelope 50x90x51.6 mm (1.969x3.543x2.031 in), outer ring 22 mm wide, C 29.6 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,200 r/min; mass 760 g. Rating split for the maintenance file: dynamic 29.6 kN (L10), static 23.2 kN (s0 shock check), fatigue 0.98 kN (adjusted life) — three separate uses for YAR 210-2RF/HV, none interchangeable with another. Pitch-diameter arithmetic: dm = (50+90)/2 = 70 mm; at the 2,200 r/min limiting speed the ball set runs at dn approx 1.54x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Load balance for documentation: C0 23.2 kN against C 29.6 kN gives a 0.784 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Static-first planning: the 0.45 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 50 mm shaft, not the 29.6 kN L10 value. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 50x90 mm insert on its chamfer tilts the whole spherical seat. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-210-2RF-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20 mm radial section.", "applications": [ "small packaging and labelling machines", "trough conveyor idler drives", "head- and tail-shaft pillow blocks in unit handling" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "The 32.6 mm s1 dimension is the screw seating geometry inside the 29.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 50 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 29.6/23.2 kN figures belong specifically to YAR 210-2RF/HV; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-210-2RF-HV?", "a": "Boundary dimensions: bore 50 mm, sphered OD 90 mm, overall width 51.6 mm; weight 760 g. Loads: dynamic 29.6 kN, static 23.2 kN, fatigue 0.98 kN; the only published speed is the 2,200 r/min limiting value." }, { "q": "What does the designation YAR 210-2RF/HV mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-210-2RF-HV lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-210-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-210", "equiv_brand": "SKF", "level": "partial", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (29.6/23.2 kN vs 35.1/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (29.6/23.2 kN vs 35.1/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (29.6/23.2 kN vs 35.1/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (29.6/23.2 kN vs 35.1/23.2 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-210-2RF-HV", "YAR 210-2RF/HV" ], "locale_variants": {} }, { "sku": "YAR-210-2RFGR-HV", "brand": "SKF", "manufacturer_designation": "YAR 210-2RFGR/HV", "series": "YAR2-series", "type": "insert", "d_mm": 50, "D_mm": 90, "B_mm": 51.6, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 29.6, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 760, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 210-2RFGR/HV is SKF's 50 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 50x90x51.6 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. /HV identifies the stainless-steel, food-industry execution: stainless bearing components, food-compatible rubber in the seal/flinger set and food-grade grease fill — the catalogue ratings are correspondingly below the standard steel version, and the GR marking adds the lubrication groove in the sphered outside surface on the locking side. Envelope 50x90x51.6 mm (1.969x3.543x2.031 in), outer ring 22 mm wide, C 29.6 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,200 r/min; mass 760 g. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 50x90 mm insert on its chamfer tilts the whole spherical seat. Fatigue-limit check: Pu 0.98 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAR 210-2RFGR/HV — most belt-driven mounted-unit loads sit comfortably under 3.311 % of C. Spherical-seat note in numbers: the 90 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 70 = 219.911 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Capacity density: 29.6 kN from 0.760 kg of bearing steel is about 38.947 kN per kilogram, and per width millimetre the 51.6 mm unit carries 0.574 kN of dynamic capacity. Static-first planning: the 0.45 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 50 mm shaft, not the 29.6 kN L10 value. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-210-2RFGR-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20 mm radial section.", "applications": [ "trough conveyor idler drives", "small packaging and labelling machines", "ventilation and extraction fans" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The 32.6 mm s1 dimension is the screw seating geometry inside the 29.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 50 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 29.6/23.2 kN figures belong specifically to YAR 210-2RFGR/HV; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-210-2RFGR-HV?", "a": "YAR 210-2RFGR/HV measures 50 mm bore x 90 mm OD x 51.6 mm overall width (outer ring 22 mm wide), 1.969 x 3.543 x 2.031 in; mass about 760 g. SKF 17000 ratings: C 29.6 kN, C0 23.2 kN, Pu 0.98 kN, limiting speed 2,200 r/min." }, { "q": "What does the designation YAR 210-2RFGR/HV mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. /HV identifies the stainless-steel, food-industry execution: stainless bearing components, food-compatible rubber in the seal/flinger set and food-grade grease fill — the catalogue ratings are correspondingly below the standard steel version, and the GR marking adds the lubrication groove in the sphered outside surface on the locking side." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR-210-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-210", "equiv_brand": "SKF", "level": "partial", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (29.6/23.2 kN vs 35.1/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (29.6/23.2 kN vs 35.1/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (29.6/23.2 kN vs 35.1/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (29.6/23.2 kN vs 35.1/23.2 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-210-2RFGR-HV", "YAR 210-2RFGR/HV" ], "locale_variants": {} }, { "sku": "YARAG-210", "brand": "SKF", "manufacturer_designation": "YARAG 210", "series": "YAR2-series", "type": "insert", "d_mm": 50, "D_mm": 90, "B_mm": 51.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 800, "max_rpm": 800, "weight_g": 750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YARAG 210 is a grub-screw insert bearing with the inner ring extended on both sides, 50x90x51.6 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 50x90x51.6 mm (1.969x3.543x2.031 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 800 r/min; mass 750 g. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 50x90 mm insert on its chamfer tilts the whole spherical seat. Spherical-seat note in numbers: the 90 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 70 = 219.911 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Rating split for the maintenance file: dynamic 35.1 kN (L10), static 23.2 kN (s0 shock check), fatigue 0.98 kN (adjusted life) — three separate uses for YARAG 210, none interchangeable with another. Bore-to-OD planning: OD 90 over bore 50 is a 1.8x step, while bore/overall-width gives 0.969; the spherical seat in the matching Y-housing must be specified to the 90 mm OD, not to a cylindrical housing bore. Speed ceiling of 800 r/min is the catalogue mechanical limit for THIS execution; the AG agricultural derate is deliberate, so real fan duty is planned well below it. Set-screw geometry on this size: the two 120 deg screws bear on the 50 mm shaft inside the 51.6 mm total width while the outer ring is only 22 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "trough conveyor idler drives", "ventilation and extraction fans", "small packaging and labelling machines" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Do not specify the 50 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 32.6 mm s1 dimension is the screw seating geometry inside the 29.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YARAG 210 as the grub two ag execution; other order numbers of the YARAG 210 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-210?", "a": "The catalogue envelope is 50x90x51.6 mm with a spherical outside surface; mass 750 g. Ratings C 35.1/23.2 kN, Pu 0.98 kN, limiting speed 800 r/min." }, { "q": "What does the designation YARAG 210 mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YARAG-210 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-210-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (35.1/23.2 kN vs 29.6/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (35.1/23.2 kN vs 29.6/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-210-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-210-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-210", "YARAG 210" ], "locale_variants": {} }, { "sku": "YAR-210-2RF", "brand": "SKF", "manufacturer_designation": "YAR 210-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 50, "D_mm": 90, "B_mm": 51.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 770, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 210-2RF is SKF's 50 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 50x90x51.6 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2RF upgrades the -2F package with a RUBBERIZED flinger on each side — the coated thrower closes the radial gap against fine dust and slurry better than the plain steel flinger of -2F. Envelope 50x90x51.6 mm (1.969x3.543x2.031 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,200 r/min; mass 770 g. Outer-vs-overall width: the outer ring is 22 mm wide inside the 51.6 mm total, so the extended inner ring accounts for 0.574 of the overall width (14.8 mm of axial projection per side). Speed ceiling of 2,200 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Rating split for the maintenance file: dynamic 35.1 kN (L10), static 23.2 kN (s0 shock check), fatigue 0.98 kN (adjusted life) — three separate uses for YAR 210-2RF, none interchangeable with another. Spherical-seat note in numbers: the 90 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 70 = 219.911 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Capacity density: 35.1 kN from 0.770 kg of bearing steel is about 45.584 kN per kilogram, and per width millimetre the 51.6 mm unit carries 0.68 kN of dynamic capacity. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Set-screw geometry on this size: the two 120 deg screws bear on the 50 mm shaft inside the 51.6 mm total width while the outer ring is only 22 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "head- and tail-shaft pillow blocks in unit handling", "garden and groundcare equipment" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "The 32.6 mm s1 dimension is the screw seating geometry inside the 29.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 50 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 35.1/23.2 kN figures belong specifically to YAR 210-2RF; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-210-2RF?", "a": "YAR 210-2RF measures 50 mm bore x 90 mm OD x 51.6 mm overall width (outer ring 22 mm wide), 1.969 x 3.543 x 2.031 in; mass about 770 g. SKF 17000 ratings: C 35.1 kN, C0 23.2 kN, Pu 0.98 kN, limiting speed 2,200 r/min." }, { "q": "What does the designation YAR 210-2RF mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2RF upgrades the -2F package with a RUBBERIZED flinger on each side — the coated thrower closes the radial gap against fine dust and slurry better than the plain steel flinger of -2F." }, { "q": "How is YAR-210-2RF lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 50 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-210-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (35.1/23.2 kN vs 29.6/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (35.1/23.2 kN vs 29.6/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-210", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 210 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-210-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-210-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-210-2RF", "YAR 210-2RF" ], "locale_variants": {} }, { "sku": "YAR-210-2RF-VE495", "brand": "SKF", "manufacturer_designation": "YAR 210-2RF/VE495", "series": "YAR2-series", "type": "insert", "d_mm": 50, "D_mm": 90, "B_mm": 51.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 770, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 210-2RF/VE495 is a grub-screw insert bearing with the inner ring extended on both sides, 50x90x51.6 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. VE495 denotes galvanized rings plus food-compatible sealing components and grease, aimed at humid, cleaned-down installations rather than submerged chemical duty. Envelope 50x90x51.6 mm (1.969x3.543x2.031 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,200 r/min; mass 770 g. Width accounting on this execution: 51.6 mm overall and 22 mm outer-ring width leave the housing designer 29.6 mm of inner-ring projection to accommodate the locking arrangement. Imperial procurement cross-check: 1.969 in bore, 3.543 in OD, 2.031 in overall width; the 770 g mass converts to 0.770 kg (27.2 oz) for the bill of materials. Load balance for documentation: C0 23.2 kN against C 35.1 kN gives a 0.661 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Static-first planning: the 0.45 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 50 mm shaft, not the 35.1 kN L10 value. Grease-life arithmetic is dominated by speed: at dn approx 1.54x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Zinc-coated food-range note: the VE495 plating is a functional surface, not cosmetic; clean the bore and shaft WITHOUT steel brushes or aggressive descalers, mount dry or with the approved food-grade mounting paste, and touch up damaged plating spots before commissioning the wash-down area. Service tip for YAR-210-2RF-VE495: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "garden and groundcare equipment", "trough conveyor idler drives" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 32.6 mm s1 dimension is the screw seating geometry inside the 29.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 50 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Ordering discipline for the 50 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-210-2RF-VE495?", "a": "The catalogue envelope is 50x90x51.6 mm with a spherical outside surface; mass 770 g. Ratings C 35.1/23.2 kN, Pu 0.98 kN, limiting speed 2,200 r/min." }, { "q": "What does the designation YAR 210-2RF/VE495 mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. VE495 denotes galvanized rings plus food-compatible sealing components and grease, aimed at humid, cleaned-down installations rather than submerged chemical duty." }, { "q": "How is YAR-210-2RF-VE495 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 50 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-210-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (35.1/23.2 kN vs 29.6/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (35.1/23.2 kN vs 29.6/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-210", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 210 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-210-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-210-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-210-2RF-VE495", "YAR 210-2RF/VE495" ], "locale_variants": {} }, { "sku": "YAR-210-2F", "brand": "SKF", "manufacturer_designation": "YAR 210-2F", "series": "YAR2-series", "type": "insert", "d_mm": 50, "D_mm": 90, "B_mm": 51.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 760, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 210-2F is a SKF insert bearing (Y-bearing) for a 50 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 90 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 50x90x51.6 mm (1.969x3.543x2.031 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,000 r/min; mass 760 g. Width accounting on this execution: 51.6 mm overall and 22 mm outer-ring width leave the housing designer 29.6 mm of inner-ring projection to accommodate the locking arrangement. Speed ceiling of 4,000 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 62.5 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Static-first planning: the 0.45 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 50 mm shaft, not the 35.1 kN L10 value. Capacity density: 35.1 kN from 0.760 kg of bearing steel is about 46.184 kN per kilogram, and per width millimetre the 51.6 mm unit carries 0.68 kN of dynamic capacity. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 50 mm shaft inside the 51.6 mm total width while the outer ring is only 22 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small packaging and labelling machines", "head- and tail-shaft pillow blocks in unit handling", "garden and groundcare equipment" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The 32.6 mm s1 dimension is the screw seating geometry inside the 29.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 50 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 35.1/23.2 kN figures belong specifically to YAR 210-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-210-2F?", "a": "Boundary dimensions: bore 50 mm, sphered OD 90 mm, overall width 51.6 mm; weight 760 g. Loads: dynamic 35.1 kN, static 23.2 kN, fatigue 0.98 kN; the only published speed is the 4,000 r/min limiting value." }, { "q": "What does the designation YAR 210-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "How is YAR-210-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 50 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-210-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (35.1/23.2 kN vs 29.6/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (35.1/23.2 kN vs 29.6/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-210", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 210 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-210-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-210-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-210-2F", "YAR 210-2F" ], "locale_variants": {} }, { "sku": "YAR-211-2RF", "brand": "SKF", "manufacturer_designation": "YAR 211-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 55, "D_mm": 100, "B_mm": 55.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 1900, "max_rpm": 1900, "weight_g": 1050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 211-2RF is a SKF insert bearing (Y-bearing) for a 55 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 100 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 211 carries the usual bore arithmetic — 55 mm (code 11 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments. Envelope 55x100x55.6 mm (2.165x3.937x2.189 in), outer ring 25 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,900 r/min; mass 1050 g. Selection figures for YAR 211-2RF: C0/C is 0.665, Pu 1.25 kN is 2.867 % of the 43.6 kN dynamic rating, and the 1050 g catalogue mass works out to roughly 19.091 g per millimetre of the 55 mm bore. Imperial procurement cross-check: 2.165 in bore, 3.937 in OD, 2.189 in overall width; the 1050 g mass converts to 1.050 kg (37.0 oz) for the bill of materials. Load balance for documentation: C0 29 kN against C 43.6 kN gives a 0.665 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. The s1 33.4 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. At the printed limiting speed of 1,900 r/min the mean diameter dm = 77.5 mm implies dn about 1.47x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Service tip for YAR-211-2RF: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 22.5 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "trough conveyor idler drives", "garden and groundcare equipment" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 55 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 33.4 mm s1 dimension is the screw seating geometry inside the 30.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 55 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-211-2RF?", "a": "Boundary dimensions: bore 55 mm, sphered OD 100 mm, overall width 55.6 mm; weight 1050 g. Loads: dynamic 43.6 kN, static 29 kN, fatigue 1.25 kN; the only published speed is the 1,900 r/min limiting value." }, { "q": "What does the designation YAR 211-2RF mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 211 carries the usual bore arithmetic — 55 mm (code 11 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments." }, { "q": "How is YAR-211-2RF lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 55 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-211-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 55x100x55.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 211-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-211-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 55x100x55.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 211-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-211-2RF", "YAR 211-2RF" ], "locale_variants": {} }, { "sku": "YAR-211-2F", "brand": "SKF", "manufacturer_designation": "YAR 211-2F", "series": "YAR2-series", "type": "insert", "d_mm": 55, "D_mm": 100, "B_mm": 55.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 1050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 211-2F is SKF's 55 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 55x100x55.6 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the size code 211 carries the usual bore arithmetic — 55 mm (code 11 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 55x100x55.6 mm (2.165x3.937x2.189 in), outer ring 25 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,600 r/min; mass 1050 g. Rating split for the maintenance file: dynamic 43.6 kN (L10), static 29 kN (s0 shock check), fatigue 1.25 kN (adjusted life) — three separate uses for YAR 211-2F, none interchangeable with another. Load balance for documentation: C0 29 kN against C 43.6 kN gives a 0.665 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Bore-to-OD planning: OD 100 over bore 55 is a 1.818x step, while bore/overall-width gives 0.989; the spherical seat in the matching Y-housing must be specified to the 100 mm OD, not to a cylindrical housing bore. Imperial procurement cross-check: 2.165 in bore, 3.937 in OD, 2.189 in overall width; the 1050 g mass converts to 1.050 kg (37.0 oz) for the bill of materials. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 69 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-211-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 22.5 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "garden and groundcare equipment", "trough conveyor idler drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "The 33.4 mm s1 dimension is the screw seating geometry inside the 30.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 55 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 43.6/29 kN figures belong specifically to YAR 211-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-211-2F?", "a": "YAR 211-2F measures 55 mm bore x 100 mm OD x 55.6 mm overall width (outer ring 25 mm wide), 2.165 x 3.937 x 2.189 in; mass about 1050 g. SKF 17000 ratings: C 43.6 kN, C0 29 kN, Pu 1.25 kN, limiting speed 3,600 r/min." }, { "q": "What does the designation YAR 211-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the size code 211 carries the usual bore arithmetic — 55 mm (code 11 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-211-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 55x100x55.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 211-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-211-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 55x100x55.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 211-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-211-2F", "YAR 211-2F" ], "locale_variants": {} }, { "sku": "YAR-212-2RF", "brand": "SKF", "manufacturer_designation": "YAR 212-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 60, "D_mm": 110, "B_mm": 65.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 36, "fatigue_load_limit_kN": 1.53, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 1400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 212-2RF is a SKF insert bearing (Y-bearing) for a 60 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 110 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 212 carries the usual bore arithmetic — 60 mm (code 12 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments. Envelope 60x110x65.1 mm (2.362x4.331x2.563 in), outer ring 26 mm wide, C 52.7 kN, C0 36 kN, Pu 1.53 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,800 r/min; mass 1400 g. Capacity density: 52.7 kN from 1.400 kg of bearing steel is about 37.643 kN per kilogram, and per width millimetre the 65.1 mm unit carries 0.81 kN of dynamic capacity. Grease-life arithmetic is dominated by speed: at dn approx 1.53x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Selection figures for YAR 212-2RF: C0/C is 0.683, Pu 1.53 kN is 2.903 % of the 52.7 kN dynamic rating, and the 1400 g catalogue mass works out to roughly 23.333 g per millimetre of the 60 mm bore. Load balance for documentation: C0 36 kN against C 52.7 kN gives a 0.683 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Fatigue-limit check: Pu 1.53 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAR 212-2RF — most belt-driven mounted-unit loads sit comfortably under 2.903 % of C. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Set-screw geometry on this size: the two 120 deg screws bear on the 60 mm shaft inside the 65.1 mm total width while the outer ring is only 26 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "crusher and screen auxiliary shafts", "bulk-handling conveyor drives", "agricultural harvesting machinery" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Do not specify the 60 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 39.7 mm s1 dimension is the screw seating geometry inside the 39.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 212-2RF as the grub two rf execution; other order numbers of the YAR 212 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-212-2RF?", "a": "Boundary dimensions: bore 60 mm, sphered OD 110 mm, overall width 65.1 mm; weight 1400 g. Loads: dynamic 52.7 kN, static 36 kN, fatigue 1.53 kN; the only published speed is the 1,800 r/min limiting value." }, { "q": "What does the designation YAR 212-2RF mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 212 carries the usual bore arithmetic — 60 mm (code 12 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-212-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 60x110x65.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 212-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-212-2RF", "YAR 212-2RF" ], "locale_variants": {} }, { "sku": "YAR-212-2F", "brand": "SKF", "manufacturer_designation": "YAR 212-2F", "series": "YAR2-series", "type": "insert", "d_mm": 60, "D_mm": 110, "B_mm": 65.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 36, "fatigue_load_limit_kN": 1.53, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 212-2F is a grub-screw insert bearing with the inner ring extended on both sides, 60x110x65.1 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 212 carries the usual bore arithmetic — 60 mm (code 12 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 60x110x65.1 mm (2.362x4.331x2.563 in), outer ring 26 mm wide, C 52.7 kN, C0 36 kN, Pu 1.53 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,400 r/min; mass 1400 g. At the printed limiting speed of 3,400 r/min the mean diameter dm = 85 mm implies dn about 2.89x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 75.6 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Rating split for the maintenance file: dynamic 52.7 kN (L10), static 36 kN (s0 shock check), fatigue 1.53 kN (adjusted life) — three separate uses for YAR 212-2F, none interchangeable with another. Imperial procurement cross-check: 2.362 in bore, 4.331 in OD, 2.563 in overall width; the 1400 g mass converts to 1.400 kg (49.4 oz) for the bill of materials. Fillet discipline: the printed r_min 1.5 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 60x110 mm insert on its chamfer tilts the whole spherical seat. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 60 mm shaft inside the 65.1 mm total width while the outer ring is only 26 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "agricultural harvesting machinery", "crusher and screen auxiliary shafts", "heavy fan and heater units" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 60 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 39.7 mm s1 dimension is the screw seating geometry inside the 39.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAR 212-2F as the grub two f execution; other order numbers of the YAR 212 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-212-2F?", "a": "The catalogue envelope is 60x110x65.1 mm with a spherical outside surface; mass 1400 g. Ratings C 52.7/36 kN, Pu 1.53 kN, limiting speed 3,400 r/min." }, { "q": "What does the designation YAR 212-2F mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 212 carries the usual bore arithmetic — 60 mm (code 12 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-212-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-212-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 60x110x65.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 212-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-212-2F", "YAR 212-2F" ], "locale_variants": {} }, { "sku": "YAR-213-2RF", "brand": "SKF", "manufacturer_designation": "YAR 213-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 65, "D_mm": 120, "B_mm": 68.3, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 57.2, "static_load_kN": 40, "fatigue_load_limit_kN": 1.7, "limiting_speed_rpm": 1600, "max_rpm": 1600, "weight_g": 1800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 213-2RF is a SKF insert bearing (Y-bearing) for a 65 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 120 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 213 carries the usual bore arithmetic — 65 mm (code 13 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments. Envelope 65x120x68.3 mm (2.559x4.724x2.689 in), outer ring 27 mm wide, C 57.2 kN, C0 40 kN, Pu 1.7 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,600 r/min; mass 1800 g. Fillet discipline: the printed r_min 1.5 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 65x120 mm insert on its chamfer tilts the whole spherical seat. Pitch-diameter arithmetic: dm = (65+120)/2 = 92.5 mm; at the 1,600 r/min limiting speed the ball set runs at dn approx 1.48x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Selection figures for YAR 213-2RF: C0/C is 0.699, Pu 1.7 kN is 2.972 % of the 57.2 kN dynamic rating, and the 1800 g catalogue mass works out to roughly 27.692 g per millimetre of the 65 mm bore. The s1 42.9 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. At the printed limiting speed of 1,600 r/min the mean diameter dm = 92.5 mm implies dn about 1.48x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Set-screw geometry on this size: the two 120 deg screws bear on the 65 mm shaft inside the 68.3 mm total width while the outer ring is only 27 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "heavy fan and heater units", "crusher and screen auxiliary shafts", "bulk-handling conveyor drives" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The 42.9 mm s1 dimension is the screw seating geometry inside the 41.3 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 65 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 57.2/40 kN figures belong specifically to YAR 213-2RF; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-213-2RF?", "a": "Boundary dimensions: bore 65 mm, sphered OD 120 mm, overall width 68.3 mm; weight 1800 g. Loads: dynamic 57.2 kN, static 40 kN, fatigue 1.7 kN; the only published speed is the 1,600 r/min limiting value." }, { "q": "What does the designation YAR 213-2RF mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 213 carries the usual bore arithmetic — 65 mm (code 13 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-213-2RF lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-213-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 65x120x68.3 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 213-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-213-2RF", "YAR 213-2RF" ], "locale_variants": {} }, { "sku": "YAR-213-2F", "brand": "SKF", "manufacturer_designation": "YAR 213-2F", "series": "YAR2-series", "type": "insert", "d_mm": 65, "D_mm": 120, "B_mm": 68.3, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 57.2, "static_load_kN": 40, "fatigue_load_limit_kN": 1.7, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 213-2F is a SKF insert bearing (Y-bearing) for a 65 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 120 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 213 carries the usual bore arithmetic — 65 mm (code 13 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 65x120x68.3 mm (2.559x4.724x2.689 in), outer ring 27 mm wide, C 57.2 kN, C0 40 kN, Pu 1.7 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,000 r/min; mass 1800 g. Envelope arithmetic: the radial section from 65 mm bore to 120 mm OD is 27.5 mm; dividing C 57.2 kN by that section gives 2.08 kN per section millimetre, and the 68.3 mm overall width is 2.484x the section. Mass-to-load ratio for YAR-213-2F: 31.469 g of catalogue mass per rated kN of C, and 27.692 g per millimetre of bore — useful when comparing executions of the same 65x120 mm envelope on the drawing. Width accounting on this execution: 68.3 mm overall and 27 mm outer-ring width leave the housing designer 41.3 mm of inner-ring projection to accommodate the locking arrangement. Static-first planning: the 0.586 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 65 mm shaft, not the 57.2 kN L10 value. Grease-life arithmetic is dominated by speed: at dn approx 2.77x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 65 mm shaft inside the 68.3 mm total width while the outer ring is only 27 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "heavy fan and heater units", "crusher and screen auxiliary shafts", "bulk-handling conveyor drives" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "The 42.9 mm s1 dimension is the screw seating geometry inside the 41.3 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 65 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 57.2/40 kN figures belong specifically to YAR 213-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-213-2F?", "a": "Boundary dimensions: bore 65 mm, sphered OD 120 mm, overall width 68.3 mm; weight 1800 g. Loads: dynamic 57.2 kN, static 40 kN, fatigue 1.7 kN; the only published speed is the 3,000 r/min limiting value." }, { "q": "What does the designation YAR 213-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 213 carries the usual bore arithmetic — 65 mm (code 13 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-213-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 65x120x68.3 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 213-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-213-2F", "YAR 213-2F" ], "locale_variants": {} }, { "sku": "YAR-214-2F", "brand": "SKF", "manufacturer_designation": "YAR 214-2F", "series": "YAR2-series", "type": "insert", "d_mm": 70, "D_mm": 125, "B_mm": 69.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 62.4, "static_load_kN": 45, "fatigue_load_limit_kN": 1.86, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 1950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 214-2F is a SKF insert bearing (Y-bearing) for a 70 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 125 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 214 carries the usual bore arithmetic — 70 mm (code 14 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 70x125x69.9 mm (2.756x4.921x2.752 in), outer ring 28 mm wide, C 62.4 kN, C0 45 kN, Pu 1.86 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,800 r/min; mass 1950 g. Pitch-diameter arithmetic: dm = (70+125)/2 = 97.5 mm; at the 2,800 r/min limiting speed the ball set runs at dn approx 2.73x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Capacity density: 62.4 kN from 1.950 kg of bearing steel is about 32 kN per kilogram, and per width millimetre the 69.9 mm unit carries 0.893 kN of dynamic capacity. Bore-to-OD planning: OD 125 over bore 70 is a 1.786x step, while bore/overall-width gives 1.001; the spherical seat in the matching Y-housing must be specified to the 125 mm OD, not to a cylindrical housing bore. Fillet discipline: the printed r_min 1.5 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 70x125 mm insert on its chamfer tilts the whole spherical seat. At the printed limiting speed of 2,800 r/min the mean diameter dm = 97.5 mm implies dn about 2.73x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-214-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 27.5 mm radial section.", "applications": [ "heavy fan and heater units", "agricultural harvesting machinery", "crusher and screen auxiliary shafts" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 39.7 mm s1 dimension is the screw seating geometry inside the 41.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 70 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Ordering discipline for the 70 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-214-2F?", "a": "Boundary dimensions: bore 70 mm, sphered OD 125 mm, overall width 69.9 mm; weight 1950 g. Loads: dynamic 62.4 kN, static 45 kN, fatigue 1.86 kN; the only published speed is the 2,800 r/min limiting value." }, { "q": "What does the designation YAR 214-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 214 carries the usual bore arithmetic — 70 mm (code 14 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-214-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-214-2F", "YAR 214-2F" ], "locale_variants": {} }, { "sku": "YAR-215-2F", "brand": "SKF", "manufacturer_designation": "YAR 215-2F", "series": "YAR2-series", "type": "insert", "d_mm": 75, "D_mm": 130, "B_mm": 73.3, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 66.3, "static_load_kN": 49, "fatigue_load_limit_kN": 2.04, "limiting_speed_rpm": 2600, "max_rpm": 2600, "weight_g": 2150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 215-2F is a SKF insert bearing (Y-bearing) for a 75 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 130 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 215 carries the usual bore arithmetic — 75 mm (code 15 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 75x130x73.3 mm (2.953x5.118x2.886 in), outer ring 29 mm wide, C 66.3 kN, C0 49 kN, Pu 2.04 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,600 r/min; mass 2150 g. Capacity density: 66.3 kN from 2.150 kg of bearing steel is about 30.837 kN per kilogram, and per width millimetre the 73.3 mm unit carries 0.905 kN of dynamic capacity. Spherical-seat note in numbers: the 130 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 102.5 = 322.013 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. The s1 46.3 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Imperial procurement cross-check: 2.953 in bore, 5.118 in OD, 2.886 in overall width; the 2150 g mass converts to 2.150 kg (75.8 oz) for the bill of materials. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 92 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-215-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 27.5 mm radial section.", "applications": [ "crusher and screen auxiliary shafts", "bulk-handling conveyor drives", "agricultural harvesting machinery" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Do not specify the 75 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 46.3 mm s1 dimension is the screw seating geometry inside the 44.3 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 215-2F as the grub two f execution; other order numbers of the YAR 215 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-215-2F?", "a": "Boundary dimensions: bore 75 mm, sphered OD 130 mm, overall width 73.3 mm; weight 2150 g. Loads: dynamic 66.3 kN, static 49 kN, fatigue 2.04 kN; the only published speed is the 2,600 r/min limiting value." }, { "q": "What does the designation YAR 215-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 215 carries the usual bore arithmetic — 75 mm (code 15 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-215-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-215-215-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 75x130x73.3 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 215-215-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 75 mm vs 74.6125 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-215-2F", "YAR 215-2F" ], "locale_variants": {} }, { "sku": "YAR-216-2F", "brand": "SKF", "manufacturer_designation": "YAR 216-2F", "series": "YAR2-series", "type": "insert", "d_mm": 80, "D_mm": 140, "B_mm": 77.8, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 72.8, "static_load_kN": 53, "fatigue_load_limit_kN": 2.16, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 2500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 216-2F is a SKF insert bearing (Y-bearing) for a 80 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 140 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 216 carries the usual bore arithmetic — 80 mm (code 16 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 80x140x77.8 mm (3.15x5.512x3.063 in), outer ring 30 mm wide, C 72.8 kN, C0 53 kN, Pu 2.16 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,400 r/min; mass 2500 g. Bore-to-OD planning: OD 140 over bore 80 is a 1.75x step, while bore/overall-width gives 1.028; the spherical seat in the matching Y-housing must be specified to the 140 mm OD, not to a cylindrical housing bore. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 97.4 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Static-first planning: the 0.681 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 80 mm shaft, not the 72.8 kN L10 value. Width accounting on this execution: 77.8 mm overall and 30 mm outer-ring width leave the housing designer 47.8 mm of inner-ring projection to accommodate the locking arrangement. Load balance for documentation: C0 53 kN against C 72.8 kN gives a 0.728 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-216-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 30 mm radial section.", "applications": [ "heavy fan and heater units", "crusher and screen auxiliary shafts", "bulk-handling conveyor drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 47.6 mm s1 dimension is the screw seating geometry inside the 47.8 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 80 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Ordering discipline for the 80 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-216-2F?", "a": "Boundary dimensions: bore 80 mm, sphered OD 140 mm, overall width 77.8 mm; weight 2500 g. Loads: dynamic 72.8 kN, static 53 kN, fatigue 2.16 kN; the only published speed is the 2,400 r/min limiting value." }, { "q": "What does the designation YAR 216-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 216 carries the usual bore arithmetic — 80 mm (code 16 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-216-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-216-2F", "YAR 216-2F" ], "locale_variants": {} }, { "sku": "YAR-218-2F", "brand": "SKF", "manufacturer_designation": "YAR 218-2F", "series": "YAR2-series", "type": "insert", "d_mm": 90, "D_mm": 160, "B_mm": 89, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 95.6, "static_load_kN": 72, "fatigue_load_limit_kN": 2.7, "limiting_speed_rpm": 2000, "max_rpm": 2000, "weight_g": 4000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 218-2F is a SKF insert bearing (Y-bearing) for a 90 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 160 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 218 carries the usual bore arithmetic — 90 mm (code 18 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 90x160x89 mm (3.543x6.299x3.504 in), outer ring 36 mm wide, C 95.6 kN, C0 72 kN, Pu 2.7 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,000 r/min; mass 4000 g. Load balance for documentation: C0 72 kN against C 95.6 kN gives a 0.753 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Width accounting on this execution: 89 mm overall and 36 mm outer-ring width leave the housing designer 53 mm of inner-ring projection to accommodate the locking arrangement. Imperial procurement cross-check: 3.543 in bore, 6.299 in OD, 3.504 in overall width; the 4000 g mass converts to 4.000 kg (141.1 oz) for the bill of materials. Envelope arithmetic: the radial section from 90 mm bore to 160 mm OD is 35 mm; dividing C 95.6 kN by that section gives 2.731 kN per section millimetre, and the 89 mm overall width is 2.543x the section. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 112 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-218-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 35 mm radial section.", "applications": [ "bulk-handling conveyor drives", "agricultural harvesting machinery", "heavy fan and heater units" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "The 54 mm s1 dimension is the screw seating geometry inside the 53 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 90 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 95.6/72 kN figures belong specifically to YAR 218-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-218-2F?", "a": "Boundary dimensions: bore 90 mm, sphered OD 160 mm, overall width 89 mm; weight 4000 g. Loads: dynamic 95.6 kN, static 72 kN, fatigue 2.7 kN; the only published speed is the 2,000 r/min limiting value." }, { "q": "What does the designation YAR 218-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the size code 218 carries the usual bore arithmetic — 90 mm (code 18 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-218-2F", "YAR 218-2F" ], "locale_variants": {} }, { "sku": "YAR-220-2F", "brand": "SKF", "manufacturer_designation": "YAR 220-2F", "series": "YAR2-series", "type": "insert", "d_mm": 100, "D_mm": 180, "B_mm": 98.4, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 124, "static_load_kN": 93, "fatigue_load_limit_kN": 3.35, "limiting_speed_rpm": 1900, "max_rpm": 1900, "weight_g": 5600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 220-2F is a grub-screw insert bearing with the inner ring extended on both sides, 100x180x98.4 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 220 carries the usual bore arithmetic — 100 mm (code 20 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 100x180x98.4 mm (3.937x7.087x3.874 in), outer ring 40 mm wide, C 124 kN, C0 93 kN, Pu 3.35 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,900 r/min; mass 5600 g. Pitch-diameter arithmetic: dm = (100+180)/2 = 140 mm; at the 1,900 r/min limiting speed the ball set runs at dn approx 2.66x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Static-first planning: the 0.945 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 100 mm shaft, not the 124 kN L10 value. Rating split for the maintenance file: dynamic 124 kN (L10), static 93 kN (s0 shock check), fatigue 3.35 kN (adjusted life) — three separate uses for YAR 220-2F, none interchangeable with another. Bore-to-OD planning: OD 180 over bore 100 is a 1.8x step, while bore/overall-width gives 1.016; the spherical seat in the matching Y-housing must be specified to the 180 mm OD, not to a cylindrical housing bore. Width accounting on this execution: 98.4 mm overall and 40 mm outer-ring width leave the housing designer 58.4 mm of inner-ring projection to accommodate the locking arrangement. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 100 mm shaft inside the 98.4 mm total width while the outer ring is only 40 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "large bulk-material conveyors", "quarry feeder and pick-up shafts" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Do not specify the 100 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 63.4 mm s1 dimension is the screw seating geometry inside the 58.4 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAR 220-2F as the grub two f execution; other order numbers of the YAR 220 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-220-2F?", "a": "The catalogue envelope is 100x180x98.4 mm with a spherical outside surface; mass 5600 g. Ratings C 124/93 kN, Pu 3.35 kN, limiting speed 1,900 r/min." }, { "q": "What does the designation YAR 220-2F mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. the size code 220 carries the usual bore arithmetic — 100 mm (code 20 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-220-2F", "YAR 220-2F" ], "locale_variants": {} }, { "sku": "YAR-203-008-2F", "brand": "SKF", "manufacturer_designation": "YAR 203-008-2F", "series": "YAR2-series", "type": "insert", "d_mm": 12.7, "D_mm": 40, "B_mm": 27.4, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 9.56, "static_load_kN": 4.75, "fatigue_load_limit_kN": 0.2, "limiting_speed_rpm": 9500, "max_rpm": 9500, "weight_g": 120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 203-008-2F is a SKF insert bearing (Y-bearing) for a 12.7 mm (0.5 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 40 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -008 decodes as 0\" +8/16, i.e. 12.7 mm; the metric coded size YAR 203 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 12.7x40x27.4 mm (0.5x1.575x1.079 in), outer ring 12 mm wide, C 9.56 kN, C0 4.75 kN, Pu 0.2 kN. The catalogue publishes a single speed ceiling, the limiting speed: 9,500 r/min; mass 120 g. Speed ceiling of 9,500 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Bore-to-OD planning: OD 40 over bore 12.7 is a 3.15x step, while bore/overall-width gives 0.464; the spherical seat in the matching Y-housing must be specified to the 40 mm OD, not to a cylindrical housing bore. Pitch-diameter arithmetic: dm = (12.7+40)/2 = 26.35 mm; at the 9,500 r/min limiting speed the ball set runs at dn approx 2.50x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Load balance for documentation: C0 4.75 kN against C 9.56 kN gives a 0.497 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Mass-to-load ratio for YAR-203-008-2F: 12.552 g of catalogue mass per rated kN of C, and 9.449 g per millimetre of bore — useful when comparing executions of the same 12.7x40 mm envelope on the drawing. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-203-008-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 13.65 mm radial section.", "applications": [ "fan and blower pillow blocks", "textile machinery rollers", "light conveyors and small belt take-ups" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 12.7 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 15.9 mm s1 dimension is the screw seating geometry inside the 15.4 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 12.7 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-203-008-2F?", "a": "Boundary dimensions: bore 12.7 mm, sphered OD 40 mm, overall width 27.4 mm; weight 120 g. Loads: dynamic 9.56 kN, static 4.75 kN, fatigue 0.2 kN; the only published speed is the 9,500 r/min limiting value." }, { "q": "What does the designation YAR 203-008-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -008 decodes as 0\" +8/16, i.e. 12.7 mm; the metric coded size YAR 203 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "How do the set screws lock the 12.7 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-203-008-2F", "YAR 203-008-2F" ], "locale_variants": {} }, { "sku": "YAT-203-010", "brand": "SKF", "manufacturer_designation": "YAT 203-010", "series": "YAR2-series", "type": "insert", "d_mm": 15.875, "D_mm": 40, "B_mm": 22.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 9.56, "static_load_kN": 4.75, "fatigue_load_limit_kN": 0.2, "limiting_speed_rpm": 9500, "max_rpm": 9500, "weight_g": 90, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAT 203-010 is SKF's 15.875 mm-bore grub-screw insert bearing with the inner ring extended on one side in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 15.875x40x22.1 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAT prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring is extended on one side only. the three-digit -010 tail codes the bore in inches for inch-shaft bearings: 0 whole inch 10/16 in = 15.875 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 22.1 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals. Envelope 15.875x40x22.1 mm (0.625x1.575x0.87 in), outer ring 12 mm wide, C 9.56 kN, C0 4.75 kN, Pu 0.2 kN. The catalogue publishes a single speed ceiling, the limiting speed: 9,500 r/min; mass 90 g. Pitch-diameter arithmetic: dm = (15.875+40)/2 = 27.938 mm; at the 9,500 r/min limiting speed the ball set runs at dn approx 2.65x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Spherical-seat note in numbers: the 40 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 27.938 = 87.77 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fatigue-limit check: Pu 0.2 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAT 203-010 — most belt-driven mounted-unit loads sit comfortably under 2.092 % of C. Bore-to-OD planning: OD 40 over bore 15.875 is a 2.52x step, while bore/overall-width gives 0.718; the spherical seat in the matching Y-housing must be specified to the 40 mm OD, not to a cylindrical housing bore. Speed ceiling of 9,500 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Set-screw geometry on this size: the two 120 deg screws bear on the 15.875 mm shaft inside the 22.1 mm total width while the outer ring is only 12 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "textile machinery rollers", "light conveyors and small belt take-ups", "fan and blower pillow blocks" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 15.9 mm s1 dimension is the screw seating geometry inside the 10.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 15.875 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Ordering discipline for the 15.875 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-203-010?", "a": "YAT 203-010 measures 15.875 mm bore x 40 mm OD x 22.1 mm overall width (outer ring 12 mm wide), 0.625 x 1.575 x 0.87 in; mass about 90 g. SKF 17000 ratings: C 9.56 kN, C0 4.75 kN, Pu 0.2 kN, limiting speed 9,500 r/min." }, { "q": "What does the designation YAT 203-010 mean?", "a": "the YAT prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring is extended on one side only. the three-digit -010 tail codes the bore in inches for inch-shaft bearings: 0 whole inch 10/16 in = 15.875 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 22.1 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAT-203-010 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-203-010", "YAT 203-010" ], "locale_variants": {} }, { "sku": "YAR-203-010-2F", "brand": "SKF", "manufacturer_designation": "YAR 203-010-2F", "series": "YAR2-series", "type": "insert", "d_mm": 15.875, "D_mm": 40, "B_mm": 27.4, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 9.56, "static_load_kN": 4.75, "fatigue_load_limit_kN": 0.2, "limiting_speed_rpm": 9500, "max_rpm": 9500, "weight_g": 100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 203-010-2F is a grub-screw insert bearing with the inner ring extended on both sides, 15.875x40x27.4 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -010 = 15.875 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 15.875x40x27.4 mm (0.625x1.575x1.079 in), outer ring 12 mm wide, C 9.56 kN, C0 4.75 kN, Pu 0.2 kN. The catalogue publishes a single speed ceiling, the limiting speed: 9,500 r/min; mass 100 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 24.2 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Selection figures for YAR 203-010-2F: C0/C is 0.497, Pu 0.2 kN is 2.092 % of the 9.56 kN dynamic rating, and the 100 g catalogue mass works out to roughly 6.299 g per millimetre of the 15.875 mm bore. Capacity density: 9.56 kN from 0.100 kg of bearing steel is about 95.6 kN per kilogram, and per width millimetre the 27.4 mm unit carries 0.349 kN of dynamic capacity. Load balance for documentation: C0 4.75 kN against C 9.56 kN gives a 0.497 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Imperial procurement cross-check: 0.625 in bore, 1.575 in OD, 1.079 in overall width; the 100 g mass converts to 0.100 kg (3.5 oz) for the bill of materials. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 15.875 mm shaft inside the 27.4 mm total width while the outer ring is only 12 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small agricultural augers", "textile machinery rollers", "fan and blower pillow blocks" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 15.875 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 15.9 mm s1 dimension is the screw seating geometry inside the 15.4 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 203-010-2F as the grub two f execution; other order numbers of the YAR 203-010 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-203-010-2F?", "a": "The catalogue envelope is 15.875x40x27.4 mm with a spherical outside surface; mass 100 g. Ratings C 9.56/4.75 kN, Pu 0.2 kN, limiting speed 9,500 r/min." }, { "q": "What does the designation YAR 203-010-2F mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -010 = 15.875 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "How do the set screws lock the 15.875 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-203-010-2F", "YAR 203-010-2F" ], "locale_variants": {} }, { "sku": "YAT-204-012", "brand": "SKF", "manufacturer_designation": "YAT 204-012", "series": "YAR2-series", "type": "insert", "d_mm": 19.049999999999997, "D_mm": 47, "B_mm": 25.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 140, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAT 204-012 is a grub-screw insert bearing with the inner ring extended on one side, 19.049999999999997x47x25.5 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -012 = 19.05 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 19.049999999999997x47x25.5 mm (0.75x1.85x1.004 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. The catalogue publishes a single speed ceiling, the limiting speed: 8,500 r/min; mass 140 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 28.2 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Capacity density: 12.7 kN from 0.140 kg of bearing steel is about 90.714 kN per kilogram, and per width millimetre the 25.5 mm unit carries 0.498 kN of dynamic capacity. Width accounting on this execution: 25.5 mm overall and 14 mm outer-ring width leave the housing designer 11.5 mm of inner-ring projection to accommodate the locking arrangement. The s1 18.3 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Selection figures for YAT 204-012: C0/C is 0.516, Pu 0.28 kN is 2.205 % of the 12.7 kN dynamic rating, and the 140 g catalogue mass works out to roughly 7.349 g per millimetre of the 19.049999999999997 mm bore. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Set-screw geometry on this size: the two 120 deg screws bear on the 19.049999999999997 mm shaft inside the 25.5 mm total width while the outer ring is only 14 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small agricultural augers", "textile machinery rollers", "fan and blower pillow blocks" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 19.049999999999997 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 18.3 mm s1 dimension is the screw seating geometry inside the 11.5 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAT 204-012 as the grub one open execution; other order numbers of the YAT 204-012 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-204-012?", "a": "The catalogue envelope is 19.049999999999997x47x25.5 mm with a spherical outside surface; mass 140 g. Ratings C 12.7/6.55 kN, Pu 0.28 kN, limiting speed 8,500 r/min." }, { "q": "What does the designation YAT 204-012 mean?", "a": "YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -012 = 19.05 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAT-204-012 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-204-012", "YAT 204-012" ], "locale_variants": {} }, { "sku": "YAR-204-012-2RF-HV", "brand": "SKF", "manufacturer_designation": "YAR 204-012-2RF/HV", "series": "YAR2-series", "type": "insert", "d_mm": 19.049999999999997, "D_mm": 47, "B_mm": 31, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 10.8, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 160, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 204-012-2RF/HV is a SKF insert bearing (Y-bearing) for a 19.049999999999997 mm (0.75 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 47 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -012 decodes as 0\" +12/16, i.e. 19.05 mm; the metric coded size YAR 204 shares the same envelope but its bore is the metric value, not this one. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part. Envelope 19.049999999999997x47x31 mm (0.75x1.85x1.22 in), outer ring 14 mm wide, C 10.8 kN, C0 6.55 kN, Pu 0.28 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,000 r/min; mass 160 g. Spherical-seat note in numbers: the 47 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 33.025 = 103.751 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Selection figures for YAR 204-012-2RF/HV: C0/C is 0.606, Pu 0.28 kN is 2.593 % of the 10.8 kN dynamic rating, and the 160 g catalogue mass works out to roughly 8.399 g per millimetre of the 19.049999999999997 mm bore. Static-first planning: the 0.211 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 19.049999999999997 mm shaft, not the 10.8 kN L10 value. Pitch-diameter arithmetic: dm = (19.049999999999997+47)/2 = 33.025 mm; at the 5,000 r/min limiting speed the ball set runs at dn approx 1.65x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Fatigue-limit check: Pu 0.28 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAR 204-012-2RF/HV — most belt-driven mounted-unit loads sit comfortably under 2.593 % of C. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-204-012-2RF-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 13.975 mm radial section.", "applications": [ "light conveyors and small belt take-ups", "small agricultural augers", "textile machinery rollers" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The 18.3 mm s1 dimension is the screw seating geometry inside the 17 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 19.049999999999997 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 10.8/6.55 kN figures belong specifically to YAR 204-012-2RF/HV; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-204-012-2RF-HV?", "a": "Boundary dimensions: bore 19.049999999999997 mm, sphered OD 47 mm, overall width 31 mm; weight 160 g. Loads: dynamic 10.8 kN, static 6.55 kN, fatigue 0.28 kN; the only published speed is the 5,000 r/min limiting value." }, { "q": "What does the designation YAR 204-012-2RF/HV mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -012 decodes as 0\" +12/16, i.e. 19.05 mm; the metric coded size YAR 204 shares the same envelope but its bore is the metric value, not this one. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part." }, { "q": "How do the set screws lock the 19.049999999999997 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-204-012-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-012-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-204-012-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (10.8/6.55 kN vs 12.7/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-012-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (10.8/6.55 kN vs 12.7/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-012-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (10.8/6.55 kN vs 12.7/6.55 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-204-012-2RF-HV", "YAR 204-012-2RF/HV" ], "locale_variants": {} }, { "sku": "YAR-204-012-2RFGR-HV", "brand": "SKF", "manufacturer_designation": "YAR 204-012-2RFGR/HV", "series": "YAR2-series", "type": "insert", "d_mm": 19.049999999999997, "D_mm": 47, "B_mm": 31, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 10.8, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 160, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 204-012-2RFGR/HV is a grub-screw insert bearing with the inner ring extended on both sides, 19.049999999999997x47x31 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -012 = 19.05 mm, which is why this row sits beside, not on, the metric bore size. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed. Envelope 19.049999999999997x47x31 mm (0.75x1.85x1.22 in), outer ring 14 mm wide, C 10.8 kN, C0 6.55 kN, Pu 0.28 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,000 r/min; mass 160 g. Load balance for documentation: C0 6.55 kN against C 10.8 kN gives a 0.606 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Selection figures for YAR 204-012-2RFGR/HV: C0/C is 0.606, Pu 0.28 kN is 2.593 % of the 10.8 kN dynamic rating, and the 160 g catalogue mass works out to roughly 8.399 g per millimetre of the 19.049999999999997 mm bore. Mass-to-load ratio for YAR-204-012-2RFGR-HV: 14.815 g of catalogue mass per rated kN of C, and 8.399 g per millimetre of bore — useful when comparing executions of the same 19.049999999999997x47 mm envelope on the drawing. Bore-to-OD planning: OD 47 over bore 19.049999999999997 is a 2.467x step, while bore/overall-width gives 0.615; the spherical seat in the matching Y-housing must be specified to the 47 mm OD, not to a cylindrical housing bore. Speed ceiling of 5,000 r/min is the catalogue mechanical limit for THIS execution; the stainless/food-grade HV fill sets this lower value, so real fan duty is planned well below it. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Set-screw geometry on this size: the two 120 deg screws bear on the 19.049999999999997 mm shaft inside the 31 mm total width while the outer ring is only 14 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "light conveyors and small belt take-ups", "small agricultural augers", "textile machinery rollers" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 19.049999999999997 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 18.3 mm s1 dimension is the screw seating geometry inside the 17 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 204-012-2RFGR/HV as the grub two hv execution; other order numbers of the YAR 204-012 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-204-012-2RFGR-HV?", "a": "The catalogue envelope is 19.049999999999997x47x31 mm with a spherical outside surface; mass 160 g. Ratings C 10.8/6.55 kN, Pu 0.28 kN, limiting speed 5,000 r/min." }, { "q": "What does the designation YAR 204-012-2RFGR/HV mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -012 = 19.05 mm, which is why this row sits beside, not on, the metric bore size. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-204-012-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-012-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-204-012-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (10.8/6.55 kN vs 12.7/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-012-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (10.8/6.55 kN vs 12.7/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-012-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (10.8/6.55 kN vs 12.7/6.55 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-204-012-2RFGR-HV", "YAR 204-012-2RFGR/HV" ], "locale_variants": {} }, { "sku": "YAR-204-012-2RF", "brand": "SKF", "manufacturer_designation": "YAR 204-012-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 19.049999999999997, "D_mm": 47, "B_mm": 31, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 160, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 204-012-2RF is a SKF insert bearing (Y-bearing) for a 19.049999999999997 mm (0.75 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 47 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -012 decodes as 0\" +12/16, i.e. 19.05 mm; the metric coded size YAR 204 shares the same envelope but its bore is the metric value, not this one. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments. Envelope 19.049999999999997x47x31 mm (0.75x1.85x1.22 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,000 r/min; mass 160 g. Grease-life arithmetic is dominated by speed: at dn approx 1.65x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Load balance for documentation: C0 6.55 kN against C 12.7 kN gives a 0.516 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Pitch-diameter arithmetic: dm = (19.049999999999997+47)/2 = 33.025 mm; at the 5,000 r/min limiting speed the ball set runs at dn approx 1.65x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. The s1 18.3 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Imperial procurement cross-check: 0.75 in bore, 1.85 in OD, 1.22 in overall width; the 160 g mass converts to 0.160 kg (5.6 oz) for the bill of materials. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Service tip for YAR-204-012-2RF: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 13.975 mm radial section.", "applications": [ "small agricultural augers", "light conveyors and small belt take-ups", "textile machinery rollers" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The 18.3 mm s1 dimension is the screw seating geometry inside the 17 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 19.049999999999997 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 12.7/6.55 kN figures belong specifically to YAR 204-012-2RF; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-204-012-2RF?", "a": "Boundary dimensions: bore 19.049999999999997 mm, sphered OD 47 mm, overall width 31 mm; weight 160 g. Loads: dynamic 12.7 kN, static 6.55 kN, fatigue 0.28 kN; the only published speed is the 5,000 r/min limiting value." }, { "q": "What does the designation YAR 204-012-2RF mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -012 decodes as 0\" +12/16, i.e. 19.05 mm; the metric coded size YAR 204 shares the same envelope but its bore is the metric value, not this one. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-204-012-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (12.7/6.55 kN vs 10.8/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-012-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (12.7/6.55 kN vs 10.8/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-012-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-012-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-204-012-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-012-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-204-012-2RF", "YAR 204-012-2RF" ], "locale_variants": {} }, { "sku": "YAR-204-012-2RF-VE495", "brand": "SKF", "manufacturer_designation": "YAR 204-012-2RF/VE495", "series": "YAR2-series", "type": "insert", "d_mm": 19.049999999999997, "D_mm": 47, "B_mm": 31, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 160, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 204-012-2RF/VE495 is a SKF insert bearing (Y-bearing) for a 19.049999999999997 mm (0.75 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 47 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -012 decodes as 0\" +12/16, i.e. 19.05 mm; the metric coded size YAR 204 shares the same envelope but its bore is the metric value, not this one. the VE495 suffix packages zinc-coated rings with stainless-reinforced food-grade seals/flingers and food-grade lubricant — the wash-down-resistant counterpart of the standard -2RF bearing. Envelope 19.049999999999997x47x31 mm (0.75x1.85x1.22 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,000 r/min; mass 160 g. Rating split for the maintenance file: dynamic 12.7 kN (L10), static 6.55 kN (s0 shock check), fatigue 0.28 kN (adjusted life) — three separate uses for YAR 204-012-2RF/VE495, none interchangeable with another. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 28.2 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Grease-life arithmetic is dominated by speed: at dn approx 1.65x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Static-first planning: the 0.211 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 19.049999999999997 mm shaft, not the 12.7 kN L10 value. At the printed limiting speed of 5,000 r/min the mean diameter dm = 33.025 mm implies dn about 1.65x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Zinc-coated food-range note: the VE495 plating is a functional surface, not cosmetic; clean the bore and shaft WITHOUT steel brushes or aggressive descalers, mount dry or with the approved food-grade mounting paste, and touch up damaged plating spots before commissioning the wash-down area. Set-screw geometry on this size: the two 120 deg screws bear on the 19.049999999999997 mm shaft inside the 31 mm total width while the outer ring is only 14 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small agricultural augers", "fan and blower pillow blocks", "textile machinery rollers" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 19.049999999999997 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 18.3 mm s1 dimension is the screw seating geometry inside the 17 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 19.049999999999997 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-204-012-2RF-VE495?", "a": "Boundary dimensions: bore 19.049999999999997 mm, sphered OD 47 mm, overall width 31 mm; weight 160 g. Loads: dynamic 12.7 kN, static 6.55 kN, fatigue 0.28 kN; the only published speed is the 5,000 r/min limiting value." }, { "q": "What does the designation YAR 204-012-2RF/VE495 mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -012 decodes as 0\" +12/16, i.e. 19.05 mm; the metric coded size YAR 204 shares the same envelope but its bore is the metric value, not this one. the VE495 suffix packages zinc-coated rings with stainless-reinforced food-grade seals/flingers and food-grade lubricant — the wash-down-resistant counterpart of the standard -2RF bearing." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-204-012-2RF-VE495 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-204-012-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (12.7/6.55 kN vs 10.8/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-012-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (12.7/6.55 kN vs 10.8/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-012-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-012-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-204-012-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-012-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-204-012-2RF-VE495", "YAR 204-012-2RF/VE495" ], "locale_variants": {} }, { "sku": "YAR-204-012-2F", "brand": "SKF", "manufacturer_designation": "YAR 204-012-2F", "series": "YAR2-series", "type": "insert", "d_mm": 19.049999999999997, "D_mm": 47, "B_mm": 31, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 160, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 204-012-2F is a SKF insert bearing (Y-bearing) for a 19.049999999999997 mm (0.75 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 47 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -012 decodes as 0\" +12/16, i.e. 19.05 mm; the metric coded size YAR 204 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 19.049999999999997x47x31 mm (0.75x1.85x1.22 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. The catalogue publishes a single speed ceiling, the limiting speed: 8,500 r/min; mass 160 g. Width accounting on this execution: 31 mm overall and 14 mm outer-ring width leave the housing designer 17 mm of inner-ring projection to accommodate the locking arrangement. The s1 18.3 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Static-first planning: the 0.211 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 19.049999999999997 mm shaft, not the 12.7 kN L10 value. Spherical-seat note in numbers: the 47 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 33.025 = 103.751 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Load balance for documentation: C0 6.55 kN against C 12.7 kN gives a 0.516 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-204-012-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 13.975 mm radial section.", "applications": [ "fan and blower pillow blocks", "light conveyors and small belt take-ups", "small agricultural augers" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Do not specify the 19.049999999999997 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 18.3 mm s1 dimension is the screw seating geometry inside the 17 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAR 204-012-2F as the grub two f execution; other order numbers of the YAR 204-012 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-204-012-2F?", "a": "Boundary dimensions: bore 19.049999999999997 mm, sphered OD 47 mm, overall width 31 mm; weight 160 g. Loads: dynamic 12.7 kN, static 6.55 kN, fatigue 0.28 kN; the only published speed is the 8,500 r/min limiting value." }, { "q": "What does the designation YAR 204-012-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -012 decodes as 0\" +12/16, i.e. 19.05 mm; the metric coded size YAR 204 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "How do the set screws lock the 19.049999999999997 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-204-012-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (12.7/6.55 kN vs 10.8/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-012-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (12.7/6.55 kN vs 10.8/6.55 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-204-012-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-012-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-204-012-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 19.049999999999997x47x31 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 204-012-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-204-012-2F", "YAR 204-012-2F" ], "locale_variants": {} }, { "sku": "YAT-205-014", "brand": "SKF", "manufacturer_designation": "YAT 205-014", "series": "YAR2-series", "type": "insert", "d_mm": 22.224999999999998, "D_mm": 52, "B_mm": 27.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAT 205-014 is SKF's 22.224999999999998 mm-bore grub-screw insert bearing with the inner ring extended on one side in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 22.224999999999998x52x27.2 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAT prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring is extended on one side only. the three-digit -014 tail codes the bore in inches for inch-shaft bearings: 0 whole inch 14/16 in = 22.225 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 27.2 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals. Envelope 22.224999999999998x52x27.2 mm (0.875x2.047x1.071 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 7,000 r/min; mass 190 g. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 22.224999999999998x52 mm insert on its chamfer tilts the whole spherical seat. Pitch-diameter arithmetic: dm = (22.224999999999998+52)/2 = 37.112 mm; at the 7,000 r/min limiting speed the ball set runs at dn approx 2.60x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Capacity density: 14 kN from 0.190 kg of bearing steel is about 73.684 kN per kilogram, and per width millimetre the 27.2 mm unit carries 0.515 kN of dynamic capacity. Imperial procurement cross-check: 0.875 in bore, 2.047 in OD, 1.071 in overall width; the 190 g mass converts to 0.190 kg (6.7 oz) for the bill of materials. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 33.7 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Set-screw geometry on this size: the two 120 deg screws bear on the 22.224999999999998 mm shaft inside the 27.2 mm total width while the outer ring is only 15 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "trough conveyor idler drives", "small packaging and labelling machines" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 19.5 mm s1 dimension is the screw seating geometry inside the 12.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 22.224999999999998 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Ordering discipline for the 22.224999999999998 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-205-014?", "a": "YAT 205-014 measures 22.224999999999998 mm bore x 52 mm OD x 27.2 mm overall width (outer ring 15 mm wide), 0.875 x 2.047 x 1.071 in; mass about 190 g. SKF 17000 ratings: C 14 kN, C0 7.8 kN, Pu 0.335 kN, limiting speed 7,000 r/min." }, { "q": "What does the designation YAT 205-014 mean?", "a": "the YAT prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring is extended on one side only. the three-digit -014 tail codes the bore in inches for inch-shaft bearings: 0 whole inch 14/16 in = 22.225 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 27.2 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAT-205-014 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-205-014", "YAT 205-014" ], "locale_variants": {} }, { "sku": "YAT-205-015", "brand": "SKF", "manufacturer_designation": "YAT 205-015", "series": "YAR2-series", "type": "insert", "d_mm": 23.8125, "D_mm": 52, "B_mm": 27.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 170, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAT 205-015 is a grub-screw insert bearing with the inner ring extended on one side, 23.8125x52x27.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -015 = 23.813 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 23.8125x52x27.2 mm (0.938x2.047x1.071 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 7,000 r/min; mass 170 g. Outer-vs-overall width: the outer ring is 15 mm wide inside the 27.2 mm total, so the extended inner ring accounts for 0.449 of the overall width (12.2 mm of axial projection on the locking side). Grease-life arithmetic is dominated by speed: at dn approx 2.65x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Speed ceiling of 7,000 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Spherical-seat note in numbers: the 52 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 37.906 = 119.085 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fatigue-limit check: Pu 0.335 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAT 205-015 — most belt-driven mounted-unit loads sit comfortably under 2.393 % of C. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Set-screw geometry on this size: the two 120 deg screws bear on the 23.8125 mm shaft inside the 27.2 mm total width while the outer ring is only 15 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "garden and groundcare equipment", "small packaging and labelling machines" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 23.8125 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 19.5 mm s1 dimension is the screw seating geometry inside the 12.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAT 205-015 as the grub one open execution; other order numbers of the YAT 205-015 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-205-015?", "a": "The catalogue envelope is 23.8125x52x27.2 mm with a spherical outside surface; mass 170 g. Ratings C 14/7.8 kN, Pu 0.335 kN, limiting speed 7,000 r/min." }, { "q": "What does the designation YAT 205-015 mean?", "a": "YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -015 = 23.813 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-205-015", "YAT 205-015" ], "locale_variants": {} }, { "sku": "YAR-205-015-2RF-VE495", "brand": "SKF", "manufacturer_designation": "YAR 205-015-2RF/VE495", "series": "YAR2-series", "type": "insert", "d_mm": 23.8125, "D_mm": 52, "B_mm": 34.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 210, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 205-015-2RF/VE495 is a SKF insert bearing (Y-bearing) for a 23.8125 mm (0.938 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 52 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -015 decodes as 0\" +15/16, i.e. 23.813 mm; the metric coded size YAR 205 shares the same envelope but its bore is the metric value, not this one. the VE495 suffix packages zinc-coated rings with stainless-reinforced food-grade seals/flingers and food-grade lubricant — the wash-down-resistant counterpart of the standard -2RF bearing. Envelope 23.8125x52x34.1 mm (0.938x2.047x1.343 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 210 g. Grease-life arithmetic is dominated by speed: at dn approx 1.63x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Width accounting on this execution: 34.1 mm overall and 15 mm outer-ring width leave the housing designer 19.1 mm of inner-ring projection to accommodate the locking arrangement. Outer-vs-overall width: the outer ring is 15 mm wide inside the 34.1 mm total, so the extended inner ring accounts for 0.56 of the overall width (9.55 mm of axial projection per side). Spherical-seat note in numbers: the 52 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 37.906 = 119.085 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Speed ceiling of 4,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Zinc-coated food-range note: the VE495 plating is a functional surface, not cosmetic; clean the bore and shaft WITHOUT steel brushes or aggressive descalers, mount dry or with the approved food-grade mounting paste, and touch up damaged plating spots before commissioning the wash-down area. Set-screw geometry on this size: the two 120 deg screws bear on the 23.8125 mm shaft inside the 34.1 mm total width while the outer ring is only 15 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "small packaging and labelling machines", "garden and groundcare equipment" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 23.8125 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 19.8 mm s1 dimension is the screw seating geometry inside the 19.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 23.8125 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-205-015-2RF-VE495?", "a": "Boundary dimensions: bore 23.8125 mm, sphered OD 52 mm, overall width 34.1 mm; weight 210 g. Loads: dynamic 14 kN, static 7.8 kN, fatigue 0.335 kN; the only published speed is the 4,300 r/min limiting value." }, { "q": "What does the designation YAR 205-015-2RF/VE495 mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -015 decodes as 0\" +15/16, i.e. 23.813 mm; the metric coded size YAR 205 shares the same envelope but its bore is the metric value, not this one. the VE495 suffix packages zinc-coated rings with stainless-reinforced food-grade seals/flingers and food-grade lubricant — the wash-down-resistant counterpart of the standard -2RF bearing." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR-205-015-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 23.8125x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-015-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-205-015-2RF-VE495", "YAR 205-015-2RF/VE495" ], "locale_variants": {} }, { "sku": "YAR-205-015-2F", "brand": "SKF", "manufacturer_designation": "YAR 205-015-2F", "series": "YAR2-series", "type": "insert", "d_mm": 23.8125, "D_mm": 52, "B_mm": 34.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 205-015-2F is a SKF insert bearing (Y-bearing) for a 23.8125 mm (0.938 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 52 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -015 decodes as 0\" +15/16, i.e. 23.813 mm; the metric coded size YAR 205 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 23.8125x52x34.1 mm (0.938x2.047x1.343 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 7,000 r/min; mass 200 g. Load balance for documentation: C0 7.8 kN against C 14 kN gives a 0.557 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Envelope arithmetic: the radial section from 23.8125 mm bore to 52 mm OD is 14.094 mm; dividing C 14 kN by that section gives 0.993 kN per section millimetre, and the 34.1 mm overall width is 2.42x the section. Grease-life arithmetic is dominated by speed: at dn approx 2.65x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Pitch-diameter arithmetic: dm = (23.8125+52)/2 = 37.906 mm; at the 7,000 r/min limiting speed the ball set runs at dn approx 2.65x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Imperial procurement cross-check: 0.938 in bore, 2.047 in OD, 1.343 in overall width; the 200 g mass converts to 0.200 kg (7.1 oz) for the bill of materials. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 23.8125 mm shaft inside the 34.1 mm total width while the outer ring is only 15 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "small packaging and labelling machines", "garden and groundcare equipment" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "The 19.8 mm s1 dimension is the screw seating geometry inside the 19.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 23.8125 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 14/7.8 kN figures belong specifically to YAR 205-015-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-205-015-2F?", "a": "Boundary dimensions: bore 23.8125 mm, sphered OD 52 mm, overall width 34.1 mm; weight 200 g. Loads: dynamic 14 kN, static 7.8 kN, fatigue 0.335 kN; the only published speed is the 7,000 r/min limiting value." }, { "q": "What does the designation YAR 205-015-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -015 decodes as 0\" +15/16, i.e. 23.813 mm; the metric coded size YAR 205 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR-205-015-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 23.8125x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-015-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-205-015-2F", "YAR 205-015-2F" ], "locale_variants": {} }, { "sku": "YAT-205-100", "brand": "SKF", "manufacturer_designation": "YAT 205-100", "series": "YAR2-series", "type": "insert", "d_mm": 25.4, "D_mm": 52, "B_mm": 27.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 160, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAT 205-100 is SKF's 25.4 mm-bore grub-screw insert bearing with the inner ring extended on one side in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 25.4x52x27.2 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAT prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring is extended on one side only. the three-digit -100 tail codes the bore in inches for inch-shaft bearings: 1 whole inch = 25.4 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 27.2 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals. Envelope 25.4x52x27.2 mm (1x2.047x1.071 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 7,000 r/min; mass 160 g. Pitch-diameter arithmetic: dm = (25.4+52)/2 = 38.7 mm; at the 7,000 r/min limiting speed the ball set runs at dn approx 2.71x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Spherical-seat note in numbers: the 52 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 38.7 = 121.58 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Rating split for the maintenance file: dynamic 14 kN (L10), static 7.8 kN (s0 shock check), fatigue 0.335 kN (adjusted life) — three separate uses for YAT 205-100, none interchangeable with another. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 25.4x52 mm insert on its chamfer tilts the whole spherical seat. Capacity density: 14 kN from 0.160 kg of bearing steel is about 87.5 kN per kilogram, and per width millimetre the 27.2 mm unit carries 0.515 kN of dynamic capacity. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Set-screw geometry on this size: the two 120 deg screws bear on the 25.4 mm shaft inside the 27.2 mm total width while the outer ring is only 15 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "trough conveyor idler drives", "small packaging and labelling machines", "ventilation and extraction fans" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Do not specify the 25.4 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 19.5 mm s1 dimension is the screw seating geometry inside the 12.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAT 205-100 as the grub one open execution; other order numbers of the YAT 205-100 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-205-100?", "a": "YAT 205-100 measures 25.4 mm bore x 52 mm OD x 27.2 mm overall width (outer ring 15 mm wide), 1 x 2.047 x 1.071 in; mass about 160 g. SKF 17000 ratings: C 14 kN, C0 7.8 kN, Pu 0.335 kN, limiting speed 7,000 r/min." }, { "q": "What does the designation YAT 205-100 mean?", "a": "the YAT prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring is extended on one side only. the three-digit -100 tail codes the bore in inches for inch-shaft bearings: 1 whole inch = 25.4 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 27.2 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAT-205-100 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAT-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x27.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAT 205 is the grub-screw locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-205-100", "YAT 205-100" ], "locale_variants": {} }, { "sku": "YAR-205-100-2RF-HV", "brand": "SKF", "manufacturer_designation": "YAR 205-100-2RF/HV", "series": "YAR2-series", "type": "insert", "d_mm": 25.4, "D_mm": 52, "B_mm": 34.1, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 11.9, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 205-100-2RF/HV is a grub-screw insert bearing with the inner ring extended on both sides, 25.4x52x34.1 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -100 = 25.4 mm, which is why this row sits beside, not on, the metric bore size. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed. Envelope 25.4x52x34.1 mm (1x2.047x1.343 in), outer ring 15 mm wide, C 11.9 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 190 g. Outer-vs-overall width: the outer ring is 15 mm wide inside the 34.1 mm total, so the extended inner ring accounts for 0.56 of the overall width (9.55 mm of axial projection per side). Mass-to-load ratio for YAR-205-100-2RF-HV: 15.966 g of catalogue mass per rated kN of C, and 7.48 g per millimetre of bore — useful when comparing executions of the same 25.4x52 mm envelope on the drawing. Envelope arithmetic: the radial section from 25.4 mm bore to 52 mm OD is 13.3 mm; dividing C 11.9 kN by that section gives 0.895 kN per section millimetre, and the 34.1 mm overall width is 2.564x the section. Static-first planning: the 0.229 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 25.4 mm shaft, not the 11.9 kN L10 value. Selection figures for YAR 205-100-2RF/HV: C0/C is 0.655, Pu 0.335 kN is 2.815 % of the 11.9 kN dynamic rating, and the 190 g catalogue mass works out to roughly 7.48 g per millimetre of the 25.4 mm bore. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-205-100-2RF-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 13.3 mm radial section.", "applications": [ "small packaging and labelling machines", "garden and groundcare equipment", "head- and tail-shaft pillow blocks in unit handling" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "The 19.8 mm s1 dimension is the screw seating geometry inside the 19.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 25.4 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 11.9/7.8 kN figures belong specifically to YAR 205-100-2RF/HV; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-205-100-2RF-HV?", "a": "The catalogue envelope is 25.4x52x34.1 mm with a spherical outside surface; mass 190 g. Ratings C 11.9/7.8 kN, Pu 0.335 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YAR 205-100-2RF/HV mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -100 = 25.4 mm, which is why this row sits beside, not on, the metric bore size. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-205-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-205", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-205-100", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-100-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-100-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-100-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-205-100-2RF-HV", "YAR 205-100-2RF/HV" ], "locale_variants": {} }, { "sku": "YAR-205-100-2RFGR-HV", "brand": "SKF", "manufacturer_designation": "YAR 205-100-2RFGR/HV", "series": "YAR2-series", "type": "insert", "d_mm": 25.4, "D_mm": 52, "B_mm": 34.1, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 11.9, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 205-100-2RFGR/HV is SKF's 25.4 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 25.4x52x34.1 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -100 tail codes the bore in inches for inch-shaft bearings: 1 whole inch = 25.4 mm (first digit whole inches, next two sixteenths of an inch). /HV identifies the stainless-steel, food-industry execution: stainless bearing components, food-compatible rubber in the seal/flinger set and food-grade grease fill — the catalogue ratings are correspondingly below the standard steel version, and the GR marking adds the lubrication groove in the sphered outside surface on the locking side. Envelope 25.4x52x34.1 mm (1x2.047x1.343 in), outer ring 15 mm wide, C 11.9 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 190 g. Mass-to-load ratio for YAR-205-100-2RFGR-HV: 15.966 g of catalogue mass per rated kN of C, and 7.48 g per millimetre of bore — useful when comparing executions of the same 25.4x52 mm envelope on the drawing. Grease-life arithmetic is dominated by speed: at dn approx 1.66x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. The s1 19.8 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Selection figures for YAR 205-100-2RFGR/HV: C0/C is 0.655, Pu 0.335 kN is 2.815 % of the 11.9 kN dynamic rating, and the 190 g catalogue mass works out to roughly 7.48 g per millimetre of the 25.4 mm bore. Imperial procurement cross-check: 1 in bore, 2.047 in OD, 1.343 in overall width; the 190 g mass converts to 0.190 kg (6.7 oz) for the bill of materials. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-205-100-2RFGR-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 13.3 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "garden and groundcare equipment", "trough conveyor idler drives" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Do not specify the 25.4 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 19.8 mm s1 dimension is the screw seating geometry inside the 19.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAR 205-100-2RFGR/HV as the grub two hv execution; other order numbers of the YAR 205-100 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-205-100-2RFGR-HV?", "a": "YAR 205-100-2RFGR/HV measures 25.4 mm bore x 52 mm OD x 34.1 mm overall width (outer ring 15 mm wide), 1 x 2.047 x 1.343 in; mass about 190 g. SKF 17000 ratings: C 11.9 kN, C0 7.8 kN, Pu 0.335 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YAR 205-100-2RFGR/HV mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -100 tail codes the bore in inches for inch-shaft bearings: 1 whole inch = 25.4 mm (first digit whole inches, next two sixteenths of an inch). /HV identifies the stainless-steel, food-industry execution: stainless bearing components, food-compatible rubber in the seal/flinger set and food-grade grease fill — the catalogue ratings are correspondingly below the standard steel version, and the GR marking adds the lubrication groove in the sphered outside surface on the locking side." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-205-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-205", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-205-100", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-100-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-100-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-100-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (11.9/7.8 kN vs 14/7.8 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-205-100-2RFGR-HV", "YAR 205-100-2RFGR/HV" ], "locale_variants": {} }, { "sku": "YARAG-205-100", "brand": "SKF", "manufacturer_designation": "YARAG 205-100", "series": "YAR2-series", "type": "insert", "d_mm": 25.4, "D_mm": 52, "B_mm": 34.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 1500, "max_rpm": 1500, "weight_g": 180, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YARAG 205-100 is SKF's 25.4 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 25.4x52x34.1 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -100 tail codes the bore in inches for inch-shaft bearings: 1 whole inch = 25.4 mm (first digit whole inches, next two sixteenths of an inch). AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant. Envelope 25.4x52x34.1 mm (1x2.047x1.343 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,500 r/min; mass 180 g. Rating split for the maintenance file: dynamic 14 kN (L10), static 7.8 kN (s0 shock check), fatigue 0.335 kN (adjusted life) — three separate uses for YARAG 205-100, none interchangeable with another. Load balance for documentation: C0 7.8 kN against C 14 kN gives a 0.557 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Bore-to-OD planning: OD 52 over bore 25.4 is a 2.047x step, while bore/overall-width gives 0.745; the spherical seat in the matching Y-housing must be specified to the 52 mm OD, not to a cylindrical housing bore. Imperial procurement cross-check: 1 in bore, 2.047 in OD, 1.343 in overall width; the 180 g mass converts to 0.180 kg (6.3 oz) for the bill of materials. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 33.7 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Service tip for YARAG-205-100: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 13.3 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "garden and groundcare equipment", "trough conveyor idler drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Do not specify the 25.4 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 19.8 mm s1 dimension is the screw seating geometry inside the 19.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YARAG 205-100 as the grub two ag execution; other order numbers of the YARAG 205-100 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-205-100?", "a": "YARAG 205-100 measures 25.4 mm bore x 52 mm OD x 34.1 mm overall width (outer ring 15 mm wide), 1 x 2.047 x 1.343 in; mass about 180 g. SKF 17000 ratings: C 14 kN, C0 7.8 kN, Pu 0.335 kN, limiting speed 1,500 r/min." }, { "q": "What does the designation YARAG 205-100 mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -100 tail codes the bore in inches for inch-shaft bearings: 1 whole inch = 25.4 mm (first digit whole inches, next two sixteenths of an inch). AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-205-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 205 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-100-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-100-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-100-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-100-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-205-100", "YARAG 205-100" ], "locale_variants": {} }, { "sku": "YAR-205-100-2RF", "brand": "SKF", "manufacturer_designation": "YAR 205-100-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 25.4, "D_mm": 52, "B_mm": 34.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 205-100-2RF is a SKF insert bearing (Y-bearing) for a 25.4 mm (1 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 52 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -100 decodes as 1\", i.e. 25.4 mm; the metric coded size YAR 205 shares the same envelope but its bore is the metric value, not this one. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments. Envelope 25.4x52x34.1 mm (1x2.047x1.343 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 190 g. The s1 19.8 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Outer-vs-overall width: the outer ring is 15 mm wide inside the 34.1 mm total, so the extended inner ring accounts for 0.56 of the overall width (9.55 mm of axial projection per side). Imperial procurement cross-check: 1 in bore, 2.047 in OD, 1.343 in overall width; the 190 g mass converts to 0.190 kg (6.7 oz) for the bill of materials. Pitch-diameter arithmetic: dm = (25.4+52)/2 = 38.7 mm; at the 4,300 r/min limiting speed the ball set runs at dn approx 1.66x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Grease-life arithmetic is dominated by speed: at dn approx 1.66x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Service tip for YAR-205-100-2RF: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 13.3 mm radial section.", "applications": [ "ventilation and extraction fans", "garden and groundcare equipment", "trough conveyor idler drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The 19.8 mm s1 dimension is the screw seating geometry inside the 19.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 25.4 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 14/7.8 kN figures belong specifically to YAR 205-100-2RF; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-205-100-2RF?", "a": "Boundary dimensions: bore 25.4 mm, sphered OD 52 mm, overall width 34.1 mm; weight 190 g. Loads: dynamic 14 kN, static 7.8 kN, fatigue 0.335 kN; the only published speed is the 4,300 r/min limiting value." }, { "q": "What does the designation YAR 205-100-2RF mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -100 decodes as 1\", i.e. 25.4 mm; the metric coded size YAR 205 shares the same envelope but its bore is the metric value, not this one. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-205-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 205 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-100-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 205-100 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-100-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-100-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-205-100-2RF", "YAR 205-100-2RF" ], "locale_variants": {} }, { "sku": "YAR-205-100-2RF-VE495", "brand": "SKF", "manufacturer_designation": "YAR 205-100-2RF/VE495", "series": "YAR2-series", "type": "insert", "d_mm": 25.4, "D_mm": 52, "B_mm": 34.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 205-100-2RF/VE495 is SKF's 25.4 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 25.4x52x34.1 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -100 tail codes the bore in inches for inch-shaft bearings: 1 whole inch = 25.4 mm (first digit whole inches, next two sixteenths of an inch). /VE495 is the zinc-plated food-industry execution: zinc-coated inner and outer rings, seals and flingers with stainless-steel inserts in food-compatible rubber, and food-grade grease fill. Envelope 25.4x52x34.1 mm (1x2.047x1.343 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 190 g. Bore-to-OD planning: OD 52 over bore 25.4 is a 2.047x step, while bore/overall-width gives 0.745; the spherical seat in the matching Y-housing must be specified to the 52 mm OD, not to a cylindrical housing bore. Imperial procurement cross-check: 1 in bore, 2.047 in OD, 1.343 in overall width; the 190 g mass converts to 0.190 kg (6.7 oz) for the bill of materials. Rating split for the maintenance file: dynamic 14 kN (L10), static 7.8 kN (s0 shock check), fatigue 0.335 kN (adjusted life) — three separate uses for YAR 205-100-2RF/VE495, none interchangeable with another. Pitch-diameter arithmetic: dm = (25.4+52)/2 = 38.7 mm; at the 4,300 r/min limiting speed the ball set runs at dn approx 1.66x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Envelope arithmetic: the radial section from 25.4 mm bore to 52 mm OD is 13.3 mm; dividing C 14 kN by that section gives 1.053 kN per section millimetre, and the 34.1 mm overall width is 2.564x the section. Zinc-coated food-range note: the VE495 plating is a functional surface, not cosmetic; clean the bore and shaft WITHOUT steel brushes or aggressive descalers, mount dry or with the approved food-grade mounting paste, and touch up damaged plating spots before commissioning the wash-down area. Set-screw geometry on this size: the two 120 deg screws bear on the 25.4 mm shaft inside the 34.1 mm total width while the outer ring is only 15 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "head- and tail-shaft pillow blocks in unit handling", "trough conveyor idler drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Do not specify the 25.4 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 19.8 mm s1 dimension is the screw seating geometry inside the 19.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 205-100-2RF/VE495 as the grub two ve495 execution; other order numbers of the YAR 205-100 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-205-100-2RF-VE495?", "a": "YAR 205-100-2RF/VE495 measures 25.4 mm bore x 52 mm OD x 34.1 mm overall width (outer ring 15 mm wide), 1 x 2.047 x 1.343 in; mass about 190 g. SKF 17000 ratings: C 14 kN, C0 7.8 kN, Pu 0.335 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YAR 205-100-2RF/VE495 mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -100 tail codes the bore in inches for inch-shaft bearings: 1 whole inch = 25.4 mm (first digit whole inches, next two sixteenths of an inch). /VE495 is the zinc-plated food-industry execution: zinc-coated inner and outer rings, seals and flingers with stainless-steel inserts in food-compatible rubber, and food-grade grease fill." }, { "q": "How is YAR-205-100-2RF-VE495 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 25.4 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-205-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 205 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-100-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 205-100 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-100-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-100-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-205-100-2RF-VE495", "YAR 205-100-2RF/VE495" ], "locale_variants": {} }, { "sku": "YAR-205-100-2F", "brand": "SKF", "manufacturer_designation": "YAR 205-100-2F", "series": "YAR2-series", "type": "insert", "d_mm": 25.4, "D_mm": 52, "B_mm": 34.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 205-100-2F is a grub-screw insert bearing with the inner ring extended on both sides, 25.4x52x34.1 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -100 = 25.4 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 25.4x52x34.1 mm (1x2.047x1.343 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 7,000 r/min; mass 190 g. Width accounting on this execution: 34.1 mm overall and 15 mm outer-ring width leave the housing designer 19.1 mm of inner-ring projection to accommodate the locking arrangement. Outer-vs-overall width: the outer ring is 15 mm wide inside the 34.1 mm total, so the extended inner ring accounts for 0.56 of the overall width (9.55 mm of axial projection per side). Inner-geometry cross-reference: the catalogue shoulder diameters (d1 33.7 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. The s1 19.8 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Selection figures for YAR 205-100-2F: C0/C is 0.557, Pu 0.335 kN is 2.393 % of the 14 kN dynamic rating, and the 190 g catalogue mass works out to roughly 7.48 g per millimetre of the 25.4 mm bore. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 25.4 mm shaft inside the 34.1 mm total width while the outer ring is only 15 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "garden and groundcare equipment", "head- and tail-shaft pillow blocks in unit handling", "trough conveyor idler drives" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The 19.8 mm s1 dimension is the screw seating geometry inside the 19.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 25.4 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 14/7.8 kN figures belong specifically to YAR 205-100-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-205-100-2F?", "a": "The catalogue envelope is 25.4x52x34.1 mm with a spherical outside surface; mass 190 g. Ratings C 14/7.8 kN, Pu 0.335 kN, limiting speed 7,000 r/min." }, { "q": "What does the designation YAR 205-100-2F mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -100 = 25.4 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-205-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 205 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-205-100-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-205-100-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (14/7.8 kN vs 11.9/7.8 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 205-100 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-100-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-205-100-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 205-100-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-205-100-2F", "YAR 205-100-2F" ], "locale_variants": {} }, { "sku": "YAR-206-101-2F", "brand": "SKF", "manufacturer_designation": "YAR 206-101-2F", "series": "YAR2-series", "type": "insert", "d_mm": 26.987499999999997, "D_mm": 62, "B_mm": 38.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 206-101-2F is SKF's 26.987499999999997 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 26.987499999999997x62x38.1 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -101 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 1/16 in = 26.987 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 26.987499999999997x62x38.1 mm (1.063x2.441x1.5 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 350 g. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 26.987499999999997x62 mm insert on its chamfer tilts the whole spherical seat. Grease-life arithmetic is dominated by speed: at dn approx 2.80x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. The s1 22.2 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Mass-to-load ratio for YAR-206-101-2F: 17.949 g of catalogue mass per rated kN of C, and 12.969 g per millimetre of bore — useful when comparing executions of the same 26.987499999999997x62 mm envelope on the drawing. Capacity density: 19.5 kN from 0.350 kg of bearing steel is about 55.714 kN per kilogram, and per width millimetre the 38.1 mm unit carries 0.512 kN of dynamic capacity. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-206-101-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 17.506 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "garden and groundcare equipment", "ventilation and extraction fans" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 26.987499999999997 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Ordering discipline for the 26.987499999999997 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-206-101-2F?", "a": "YAR 206-101-2F measures 26.987499999999997 mm bore x 62 mm OD x 38.1 mm overall width (outer ring 18 mm wide), 1.063 x 2.441 x 1.5 in; mass about 350 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YAR 206-101-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -101 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 1/16 in = 26.987 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-206-101-2F", "YAR 206-101-2F" ], "locale_variants": {} }, { "sku": "YARAG-206-102", "brand": "SKF", "manufacturer_designation": "YARAG 206-102", "series": "YAR2-series", "type": "insert", "d_mm": 28.575, "D_mm": 62, "B_mm": 38.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 1200, "max_rpm": 1200, "weight_g": 320, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YARAG 206-102 is SKF's 28.575 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 28.575x62x38.1 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -102 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 2/16 in = 28.575 mm (first digit whole inches, next two sixteenths of an inch). AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant. Envelope 28.575x62x38.1 mm (1.125x2.441x1.5 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,200 r/min; mass 320 g. Fatigue-limit check: Pu 0.475 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YARAG 206-102 — most belt-driven mounted-unit loads sit comfortably under 2.436 % of C. Capacity density: 19.5 kN from 0.320 kg of bearing steel is about 60.938 kN per kilogram, and per width millimetre the 38.1 mm unit carries 0.512 kN of dynamic capacity. Width accounting on this execution: 38.1 mm overall and 18 mm outer-ring width leave the housing designer 20.1 mm of inner-ring projection to accommodate the locking arrangement. The s1 22.2 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Speed ceiling of 1,200 r/min is the catalogue mechanical limit for THIS execution; the AG agricultural derate is deliberate, so real fan duty is planned well below it. Set-screw geometry on this size: the two 120 deg screws bear on the 28.575 mm shaft inside the 38.1 mm total width while the outer ring is only 18 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "garden and groundcare equipment", "trough conveyor idler drives", "head- and tail-shaft pillow blocks in unit handling" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Do not specify the 28.575 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YARAG 206-102 as the grub two ag execution; other order numbers of the YARAG 206-102 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-206-102?", "a": "YARAG 206-102 measures 28.575 mm bore x 62 mm OD x 38.1 mm overall width (outer ring 18 mm wide), 1.125 x 2.441 x 1.5 in; mass about 320 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 1,200 r/min." }, { "q": "What does the designation YARAG 206-102 mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -102 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 2/16 in = 28.575 mm (first digit whole inches, next two sixteenths of an inch). AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YARAG-206-102 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-206-102-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 28.575x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-102-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-206-102", "YARAG 206-102" ], "locale_variants": {} }, { "sku": "YAR-206-102-2F", "brand": "SKF", "manufacturer_designation": "YAR 206-102-2F", "series": "YAR2-series", "type": "insert", "d_mm": 28.575, "D_mm": 62, "B_mm": 38.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 320, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 206-102-2F is a grub-screw insert bearing with the inner ring extended on both sides, 28.575x62x38.1 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -102 = 28.575 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 28.575x62x38.1 mm (1.125x2.441x1.5 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 320 g. Speed ceiling of 6,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Static-first planning: the 0.294 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 28.575 mm shaft, not the 19.5 kN L10 value. Load balance for documentation: C0 11.2 kN against C 19.5 kN gives a 0.574 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. The s1 22.2 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. At the printed limiting speed of 6,300 r/min the mean diameter dm = 45.288 mm implies dn about 2.85x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-206-102-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 16.712 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "small packaging and labelling machines", "ventilation and extraction fans" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 28.575 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 19.5/11.2 kN figures belong specifically to YAR 206-102-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-206-102-2F?", "a": "The catalogue envelope is 28.575x62x38.1 mm with a spherical outside surface; mass 320 g. Ratings C 19.5/11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YAR 206-102-2F mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -102 = 28.575 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YARAG-206-102", "equiv_brand": "SKF", "level": "full", "note": "Same 28.575x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 206-102 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-206-102-2F", "YAR 206-102-2F" ], "locale_variants": {} }, { "sku": "YAT-206-103", "brand": "SKF", "manufacturer_designation": "YAT 206-103", "series": "YAR2-series", "type": "insert", "d_mm": 30.162499999999998, "D_mm": 62, "B_mm": 30.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 260, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAT 206-103 is a grub-screw insert bearing with the inner ring extended on one side, 30.162499999999998x62x30.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -103 = 30.162 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 30.162499999999998x62x30.2 mm (1.188x2.441x1.189 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 260 g. Load balance for documentation: C0 11.2 kN against C 19.5 kN gives a 0.574 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. The s1 21 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Speed ceiling of 6,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 30.162499999999998x62 mm insert on its chamfer tilts the whole spherical seat. Mass-to-load ratio for YAT-206-103: 13.333 g of catalogue mass per rated kN of C, and 8.62 g per millimetre of bore — useful when comparing executions of the same 30.162499999999998x62 mm envelope on the drawing. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Set-screw geometry on this size: the two 120 deg screws bear on the 30.162499999999998 mm shaft inside the 30.2 mm total width while the outer ring is only 18 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "trough conveyor idler drives", "ventilation and extraction fans", "garden and groundcare equipment" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The 21 mm s1 dimension is the screw seating geometry inside the 12.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 30.162499999999998 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 19.5/11.2 kN figures belong specifically to YAT 206-103; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-206-103?", "a": "The catalogue envelope is 30.162499999999998x62x30.2 mm with a spherical outside surface; mass 260 g. Ratings C 19.5/11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YAT 206-103 mean?", "a": "YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -103 = 30.162 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "How do the set screws lock the 30.162499999999998 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAT-206", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x30.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAT 206 is the grub-screw locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-206-103", "YAT 206-103" ], "locale_variants": {} }, { "sku": "YAR-206-103-2RF-HV", "brand": "SKF", "manufacturer_designation": "YAR 206-103-2RF/HV", "series": "YAR2-series", "type": "insert", "d_mm": 30.162499999999998, "D_mm": 62, "B_mm": 38.1, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 16.3, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 206-103-2RF/HV is a grub-screw insert bearing with the inner ring extended on both sides, 30.162499999999998x62x38.1 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -103 = 30.162 mm, which is why this row sits beside, not on, the metric bore size. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed. Envelope 30.162499999999998x62x38.1 mm (1.188x2.441x1.5 in), outer ring 18 mm wide, C 16.3 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,800 r/min; mass 300 g. Outer-vs-overall width: the outer ring is 18 mm wide inside the 38.1 mm total, so the extended inner ring accounts for 0.528 of the overall width (10.05 mm of axial projection per side). Mass-to-load ratio for YAR-206-103-2RF-HV: 18.405 g of catalogue mass per rated kN of C, and 9.946 g per millimetre of bore — useful when comparing executions of the same 30.162499999999998x62 mm envelope on the drawing. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 30.162499999999998x62 mm insert on its chamfer tilts the whole spherical seat. Spherical-seat note in numbers: the 62 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 46.081 = 144.768 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Envelope arithmetic: the radial section from 30.162499999999998 mm bore to 62 mm OD is 15.919 mm; dividing C 16.3 kN by that section gives 1.024 kN per section millimetre, and the 38.1 mm overall width is 2.393x the section. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-206-103-2RF-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 15.919 mm radial section.", "applications": [ "ventilation and extraction fans", "garden and groundcare equipment", "small packaging and labelling machines" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 30.162499999999998 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 30.162499999999998 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-206-103-2RF-HV?", "a": "The catalogue envelope is 30.162499999999998x62x38.1 mm with a spherical outside surface; mass 300 g. Ratings C 16.3/11.2 kN, Pu 0.475 kN, limiting speed 3,800 r/min." }, { "q": "What does the designation YAR 206-103-2RF/HV mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -103 = 30.162 mm, which is why this row sits beside, not on, the metric bore size. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-206-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-206", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-206-103", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-103-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-103-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-206-103-2RF-HV", "YAR 206-103-2RF/HV" ], "locale_variants": {} }, { "sku": "YAR-206-103-2RFGR-HV", "brand": "SKF", "manufacturer_designation": "YAR 206-103-2RFGR/HV", "series": "YAR2-series", "type": "insert", "d_mm": 30.162499999999998, "D_mm": 62, "B_mm": 38.1, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 16.3, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 206-103-2RFGR/HV is a grub-screw insert bearing with the inner ring extended on both sides, 30.162499999999998x62x38.1 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -103 = 30.162 mm, which is why this row sits beside, not on, the metric bore size. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed. Envelope 30.162499999999998x62x38.1 mm (1.188x2.441x1.5 in), outer ring 18 mm wide, C 16.3 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,800 r/min; mass 300 g. Grease-life arithmetic is dominated by speed: at dn approx 1.75x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Rating split for the maintenance file: dynamic 16.3 kN (L10), static 11.2 kN (s0 shock check), fatigue 0.475 kN (adjusted life) — three separate uses for YAR 206-103-2RFGR/HV, none interchangeable with another. Static-first planning: the 0.294 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 30.162499999999998 mm shaft, not the 16.3 kN L10 value. At the printed limiting speed of 3,800 r/min the mean diameter dm = 46.081 mm implies dn about 1.75x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Pitch-diameter arithmetic: dm = (30.162499999999998+62)/2 = 46.081 mm; at the 3,800 r/min limiting speed the ball set runs at dn approx 1.75x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Set-screw geometry on this size: the two 120 deg screws bear on the 30.162499999999998 mm shaft inside the 38.1 mm total width while the outer ring is only 18 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small packaging and labelling machines", "ventilation and extraction fans", "garden and groundcare equipment" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 30.162499999999998 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 16.3/11.2 kN figures belong specifically to YAR 206-103-2RFGR/HV; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-206-103-2RFGR-HV?", "a": "The catalogue envelope is 30.162499999999998x62x38.1 mm with a spherical outside surface; mass 300 g. Ratings C 16.3/11.2 kN, Pu 0.475 kN, limiting speed 3,800 r/min." }, { "q": "What does the designation YAR 206-103-2RFGR/HV mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -103 = 30.162 mm, which is why this row sits beside, not on, the metric bore size. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed." }, { "q": "How do the set screws lock the 30.162499999999998 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-206-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-206", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-206-103", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-103-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-103-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-206-103-2RFGR-HV", "YAR 206-103-2RFGR/HV" ], "locale_variants": {} }, { "sku": "YARAG-206-103", "brand": "SKF", "manufacturer_designation": "YARAG 206-103", "series": "YAR2-series", "type": "insert", "d_mm": 30.162499999999998, "D_mm": 62, "B_mm": 38.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 1200, "max_rpm": 1200, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YARAG 206-103 is SKF's 30.162499999999998 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 30.162499999999998x62x38.1 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -103 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 3/16 in = 30.162 mm (first digit whole inches, next two sixteenths of an inch). AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant. Envelope 30.162499999999998x62x38.1 mm (1.188x2.441x1.5 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,200 r/min; mass 300 g. Rating split for the maintenance file: dynamic 19.5 kN (L10), static 11.2 kN (s0 shock check), fatigue 0.475 kN (adjusted life) — three separate uses for YARAG 206-103, none interchangeable with another. Static-first planning: the 0.294 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 30.162499999999998 mm shaft, not the 19.5 kN L10 value. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 30.162499999999998x62 mm insert on its chamfer tilts the whole spherical seat. Grease-life arithmetic is dominated by speed: at dn approx 0.55x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the AG variant caps speed so aggressively, and high-temperature mounts shorten both even when load is light. Bore-to-OD planning: OD 62 over bore 30.162499999999998 is a 2.056x step, while bore/overall-width gives 0.792; the spherical seat in the matching Y-housing must be specified to the 62 mm OD, not to a cylindrical housing bore. Service tip for YARAG-206-103: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 15.919 mm radial section.", "applications": [ "small packaging and labelling machines", "trough conveyor idler drives", "head- and tail-shaft pillow blocks in unit handling" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Do not specify the 30.162499999999998 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YARAG 206-103 as the grub two ag execution; other order numbers of the YARAG 206-103 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-206-103?", "a": "YARAG 206-103 measures 30.162499999999998 mm bore x 62 mm OD x 38.1 mm overall width (outer ring 18 mm wide), 1.188 x 2.441 x 1.5 in; mass about 300 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 1,200 r/min." }, { "q": "What does the designation YARAG 206-103 mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -103 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 3/16 in = 30.162 mm (first digit whole inches, next two sixteenths of an inch). AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR-206-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-206", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 206 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-103-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-103-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-103-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-206-103", "YARAG 206-103" ], "locale_variants": {} }, { "sku": "YAR-206-103-2RF-VE495", "brand": "SKF", "manufacturer_designation": "YAR 206-103-2RF/VE495", "series": "YAR2-series", "type": "insert", "d_mm": 30.162499999999998, "D_mm": 62, "B_mm": 38.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 206-103-2RF/VE495 is SKF's 30.162499999999998 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 30.162499999999998x62x38.1 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -103 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 3/16 in = 30.162 mm (first digit whole inches, next two sixteenths of an inch). /VE495 is the zinc-plated food-industry execution: zinc-coated inner and outer rings, seals and flingers with stainless-steel inserts in food-compatible rubber, and food-grade grease fill. Envelope 30.162499999999998x62x38.1 mm (1.188x2.441x1.5 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,800 r/min; mass 300 g. Width accounting on this execution: 38.1 mm overall and 18 mm outer-ring width leave the housing designer 20.1 mm of inner-ring projection to accommodate the locking arrangement. Imperial procurement cross-check: 1.188 in bore, 2.441 in OD, 1.5 in overall width; the 300 g mass converts to 0.300 kg (10.6 oz) for the bill of materials. The s1 22.2 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Spherical-seat note in numbers: the 62 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 46.081 = 144.768 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 39.7 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Zinc-coated food-range note: the VE495 plating is a functional surface, not cosmetic; clean the bore and shaft WITHOUT steel brushes or aggressive descalers, mount dry or with the approved food-grade mounting paste, and touch up damaged plating spots before commissioning the wash-down area. Service tip for YAR-206-103-2RF-VE495: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 15.919 mm radial section.", "applications": [ "ventilation and extraction fans", "head- and tail-shaft pillow blocks in unit handling", "small packaging and labelling machines" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 30.162499999999998 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 19.5/11.2 kN figures belong specifically to YAR 206-103-2RF/VE495; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-206-103-2RF-VE495?", "a": "YAR 206-103-2RF/VE495 measures 30.162499999999998 mm bore x 62 mm OD x 38.1 mm overall width (outer ring 18 mm wide), 1.188 x 2.441 x 1.5 in; mass about 300 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 3,800 r/min." }, { "q": "What does the designation YAR 206-103-2RF/VE495 mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -103 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 3/16 in = 30.162 mm (first digit whole inches, next two sixteenths of an inch). /VE495 is the zinc-plated food-industry execution: zinc-coated inner and outer rings, seals and flingers with stainless-steel inserts in food-compatible rubber, and food-grade grease fill." }, { "q": "How is YAR-206-103-2RF-VE495 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 30.162499999999998 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-206-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-206", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 206 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-103-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-206-103", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 206-103 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-103-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-206-103-2RF-VE495", "YAR 206-103-2RF/VE495" ], "locale_variants": {} }, { "sku": "YAR-206-103-2F", "brand": "SKF", "manufacturer_designation": "YAR 206-103-2F", "series": "YAR2-series", "type": "insert", "d_mm": 30.162499999999998, "D_mm": 62, "B_mm": 38.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 206-103-2F is SKF's 30.162499999999998 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 30.162499999999998x62x38.1 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -103 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 3/16 in = 30.162 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 30.162499999999998x62x38.1 mm (1.188x2.441x1.5 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 300 g. Imperial procurement cross-check: 1.188 in bore, 2.441 in OD, 1.5 in overall width; the 300 g mass converts to 0.300 kg (10.6 oz) for the bill of materials. Speed ceiling of 6,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Static-first planning: the 0.294 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 30.162499999999998 mm shaft, not the 19.5 kN L10 value. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 30.162499999999998x62 mm insert on its chamfer tilts the whole spherical seat. Fatigue-limit check: Pu 0.475 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAR 206-103-2F — most belt-driven mounted-unit loads sit comfortably under 2.436 % of C. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-206-103-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 15.919 mm radial section.", "applications": [ "trough conveyor idler drives", "head- and tail-shaft pillow blocks in unit handling", "ventilation and extraction fans" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 30.162499999999998 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Ordering discipline for the 30.162499999999998 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-206-103-2F?", "a": "YAR 206-103-2F measures 30.162499999999998 mm bore x 62 mm OD x 38.1 mm overall width (outer ring 18 mm wide), 1.188 x 2.441 x 1.5 in; mass about 300 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YAR 206-103-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -103 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 3/16 in = 30.162 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "How is YAR-206-103-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 30.162499999999998 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-206-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-206", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 206 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-206-103-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-103-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-206-103", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 206-103 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-103-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-103-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-206-103-2F", "YAR 206-103-2F" ], "locale_variants": {} }, { "sku": "YAT-206-104", "brand": "SKF", "manufacturer_designation": "YAT 206-104", "series": "YAR2-series", "type": "insert", "d_mm": 31.75, "D_mm": 62, "B_mm": 30.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAT 206-104 is a SKF insert bearing (Y-bearing) for a 31.75 mm (1.25 in) shaft: grub-screw insert bearing with the inner ring extended on one side, built to the ISO 15 diameter-series envelope with a sphered OD of 62 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. inch bore code -104 decodes as 1\" +4/16, i.e. 31.75 mm; the metric coded size YAT 206 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings. Envelope 31.75x62x30.2 mm (1.25x2.441x1.189 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 240 g. At the printed limiting speed of 6,300 r/min the mean diameter dm = 46.875 mm implies dn about 2.95x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Grease-life arithmetic is dominated by speed: at dn approx 2.95x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Imperial procurement cross-check: 1.25 in bore, 2.441 in OD, 1.189 in overall width; the 240 g mass converts to 0.240 kg (8.5 oz) for the bill of materials. Bore-to-OD planning: OD 62 over bore 31.75 is a 1.953x step, while bore/overall-width gives 1.051; the spherical seat in the matching Y-housing must be specified to the 62 mm OD, not to a cylindrical housing bore. Speed ceiling of 6,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Set-screw geometry on this size: the two 120 deg screws bear on the 31.75 mm shaft inside the 30.2 mm total width while the outer ring is only 18 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "trough conveyor idler drives", "garden and groundcare equipment", "ventilation and extraction fans" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Do not specify the 31.75 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 21 mm s1 dimension is the screw seating geometry inside the 12.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAT 206-104 as the grub one open execution; other order numbers of the YAT 206-104 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-206-104?", "a": "Boundary dimensions: bore 31.75 mm, sphered OD 62 mm, overall width 30.2 mm; weight 240 g. Loads: dynamic 19.5 kN, static 11.2 kN, fatigue 0.475 kN; the only published speed is the 6,300 r/min limiting value." }, { "q": "What does the designation YAT 206-104 mean?", "a": "reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. inch bore code -104 decodes as 1\" +4/16, i.e. 31.75 mm; the metric coded size YAT 206 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-206-104", "YAT 206-104" ], "locale_variants": {} }, { "sku": "YAR-206-104-2RF-HV", "brand": "SKF", "manufacturer_designation": "YAR 206-104-2RF/HV", "series": "YAR2-series", "type": "insert", "d_mm": 31.75, "D_mm": 62, "B_mm": 38.1, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 16.3, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 280, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 206-104-2RF/HV is a SKF insert bearing (Y-bearing) for a 31.75 mm (1.25 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 62 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -104 decodes as 1\" +4/16, i.e. 31.75 mm; the metric coded size YAR 206 shares the same envelope but its bore is the metric value, not this one. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part. Envelope 31.75x62x38.1 mm (1.25x2.441x1.5 in), outer ring 18 mm wide, C 16.3 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,800 r/min; mass 280 g. At the printed limiting speed of 3,800 r/min the mean diameter dm = 46.875 mm implies dn about 1.78x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Grease-life arithmetic is dominated by speed: at dn approx 1.78x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Spherical-seat note in numbers: the 62 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 46.875 = 147.262 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Rating split for the maintenance file: dynamic 16.3 kN (L10), static 11.2 kN (s0 shock check), fatigue 0.475 kN (adjusted life) — three separate uses for YAR 206-104-2RF/HV, none interchangeable with another. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 31.75x62 mm insert on its chamfer tilts the whole spherical seat. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Set-screw geometry on this size: the two 120 deg screws bear on the 31.75 mm shaft inside the 38.1 mm total width while the outer ring is only 18 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "garden and groundcare equipment", "small packaging and labelling machines" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 31.75 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 31.75 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-206-104-2RF-HV?", "a": "Boundary dimensions: bore 31.75 mm, sphered OD 62 mm, overall width 38.1 mm; weight 280 g. Loads: dynamic 16.3 kN, static 11.2 kN, fatigue 0.475 kN; the only published speed is the 3,800 r/min limiting value." }, { "q": "What does the designation YAR 206-104-2RF/HV mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -104 decodes as 1\" +4/16, i.e. 31.75 mm; the metric coded size YAR 206 shares the same envelope but its bore is the metric value, not this one. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-206-104-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-104-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-206-104", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-104-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-104-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-206-104-2RF-HV", "YAR 206-104-2RF/HV" ], "locale_variants": {} }, { "sku": "YAR-206-104-2RFGR-HV", "brand": "SKF", "manufacturer_designation": "YAR 206-104-2RFGR/HV", "series": "YAR2-series", "type": "insert", "d_mm": 31.75, "D_mm": 62, "B_mm": 38.1, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 16.3, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 280, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 206-104-2RFGR/HV is SKF's 31.75 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 31.75x62x38.1 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -104 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 4/16 in = 31.75 mm (first digit whole inches, next two sixteenths of an inch). /HV identifies the stainless-steel, food-industry execution: stainless bearing components, food-compatible rubber in the seal/flinger set and food-grade grease fill — the catalogue ratings are correspondingly below the standard steel version, and the GR marking adds the lubrication groove in the sphered outside surface on the locking side. Envelope 31.75x62x38.1 mm (1.25x2.441x1.5 in), outer ring 18 mm wide, C 16.3 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,800 r/min; mass 280 g. Rating split for the maintenance file: dynamic 16.3 kN (L10), static 11.2 kN (s0 shock check), fatigue 0.475 kN (adjusted life) — three separate uses for YAR 206-104-2RFGR/HV, none interchangeable with another. Bore-to-OD planning: OD 62 over bore 31.75 is a 1.953x step, while bore/overall-width gives 0.833; the spherical seat in the matching Y-housing must be specified to the 62 mm OD, not to a cylindrical housing bore. Imperial procurement cross-check: 1.25 in bore, 2.441 in OD, 1.5 in overall width; the 280 g mass converts to 0.280 kg (9.9 oz) for the bill of materials. Speed ceiling of 3,800 r/min is the catalogue mechanical limit for THIS execution; the stainless/food-grade HV fill sets this lower value, so real fan duty is planned well below it. Spherical-seat note in numbers: the 62 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 46.875 = 147.262 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-206-104-2RFGR-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 15.125 mm radial section.", "applications": [ "trough conveyor idler drives", "ventilation and extraction fans", "small packaging and labelling machines" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 31.75 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 31.75 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-206-104-2RFGR-HV?", "a": "YAR 206-104-2RFGR/HV measures 31.75 mm bore x 62 mm OD x 38.1 mm overall width (outer ring 18 mm wide), 1.25 x 2.441 x 1.5 in; mass about 280 g. SKF 17000 ratings: C 16.3 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 3,800 r/min." }, { "q": "What does the designation YAR 206-104-2RFGR/HV mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -104 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 4/16 in = 31.75 mm (first digit whole inches, next two sixteenths of an inch). /HV identifies the stainless-steel, food-industry execution: stainless bearing components, food-compatible rubber in the seal/flinger set and food-grade grease fill — the catalogue ratings are correspondingly below the standard steel version, and the GR marking adds the lubrication groove in the sphered outside surface on the locking side." }, { "q": "How do the set screws lock the 31.75 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-206-104-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-104-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-206-104", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-104-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-104-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (16.3/11.2 kN vs 19.5/11.2 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-206-104-2RFGR-HV", "YAR 206-104-2RFGR/HV" ], "locale_variants": {} }, { "sku": "YARAG-206-104", "brand": "SKF", "manufacturer_designation": "YARAG 206-104", "series": "YAR2-series", "type": "insert", "d_mm": 31.75, "D_mm": 62, "B_mm": 38.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 1200, "max_rpm": 1200, "weight_g": 270, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YARAG 206-104 is a SKF insert bearing (Y-bearing) for a 31.75 mm (1.25 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 62 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -104 decodes as 1\" +4/16, i.e. 31.75 mm; the metric coded size YARAG 206 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution. Envelope 31.75x62x38.1 mm (1.25x2.441x1.5 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,200 r/min; mass 270 g. Load balance for documentation: C0 11.2 kN against C 19.5 kN gives a 0.574 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Grease-life arithmetic is dominated by speed: at dn approx 0.56x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the AG variant caps speed so aggressively, and high-temperature mounts shorten both even when load is light. Mass-to-load ratio for YARAG-206-104: 13.846 g of catalogue mass per rated kN of C, and 8.504 g per millimetre of bore — useful when comparing executions of the same 31.75x62 mm envelope on the drawing. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 31.75x62 mm insert on its chamfer tilts the whole spherical seat. Capacity density: 19.5 kN from 0.270 kg of bearing steel is about 72.222 kN per kilogram, and per width millimetre the 38.1 mm unit carries 0.512 kN of dynamic capacity. Service tip for YARAG-206-104: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 15.125 mm radial section.", "applications": [ "trough conveyor idler drives", "garden and groundcare equipment", "ventilation and extraction fans" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 31.75 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Ordering discipline for the 31.75 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-206-104?", "a": "Boundary dimensions: bore 31.75 mm, sphered OD 62 mm, overall width 38.1 mm; weight 270 g. Loads: dynamic 19.5 kN, static 11.2 kN, fatigue 0.475 kN; the only published speed is the 1,200 r/min limiting value." }, { "q": "What does the designation YARAG 206-104 mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -104 decodes as 1\" +4/16, i.e. 31.75 mm; the metric coded size YARAG 206 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-206-104-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-104-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-104-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-104-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-104-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-104-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-206-104", "YARAG 206-104" ], "locale_variants": {} }, { "sku": "YAR-206-104-2RF-VE495", "brand": "SKF", "manufacturer_designation": "YAR 206-104-2RF/VE495", "series": "YAR2-series", "type": "insert", "d_mm": 31.75, "D_mm": 62, "B_mm": 38.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 280, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 206-104-2RF/VE495 is SKF's 31.75 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 31.75x62x38.1 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -104 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 4/16 in = 31.75 mm (first digit whole inches, next two sixteenths of an inch). /VE495 is the zinc-plated food-industry execution: zinc-coated inner and outer rings, seals and flingers with stainless-steel inserts in food-compatible rubber, and food-grade grease fill. Envelope 31.75x62x38.1 mm (1.25x2.441x1.5 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,800 r/min; mass 280 g. Imperial procurement cross-check: 1.25 in bore, 2.441 in OD, 1.5 in overall width; the 280 g mass converts to 0.280 kg (9.9 oz) for the bill of materials. Outer-vs-overall width: the outer ring is 18 mm wide inside the 38.1 mm total, so the extended inner ring accounts for 0.528 of the overall width (10.05 mm of axial projection per side). Load balance for documentation: C0 11.2 kN against C 19.5 kN gives a 0.574 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 31.75x62 mm insert on its chamfer tilts the whole spherical seat. Grease-life arithmetic is dominated by speed: at dn approx 1.78x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Zinc-coated food-range note: the VE495 plating is a functional surface, not cosmetic; clean the bore and shaft WITHOUT steel brushes or aggressive descalers, mount dry or with the approved food-grade mounting paste, and touch up damaged plating spots before commissioning the wash-down area. Service tip for YAR-206-104-2RF-VE495: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 15.125 mm radial section.", "applications": [ "trough conveyor idler drives", "garden and groundcare equipment", "ventilation and extraction fans" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Do not specify the 31.75 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 206-104-2RF/VE495 as the grub two ve495 execution; other order numbers of the YAR 206-104 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-206-104-2RF-VE495?", "a": "YAR 206-104-2RF/VE495 measures 31.75 mm bore x 62 mm OD x 38.1 mm overall width (outer ring 18 mm wide), 1.25 x 2.441 x 1.5 in; mass about 280 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 3,800 r/min." }, { "q": "What does the designation YAR 206-104-2RF/VE495 mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -104 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 4/16 in = 31.75 mm (first digit whole inches, next two sixteenths of an inch). /VE495 is the zinc-plated food-industry execution: zinc-coated inner and outer rings, seals and flingers with stainless-steel inserts in food-compatible rubber, and food-grade grease fill." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-206-104-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-104-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-206-104", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 206-104 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-104-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-104-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-206-104-2RF-VE495", "YAR 206-104-2RF/VE495" ], "locale_variants": {} }, { "sku": "YAR-206-104-2F", "brand": "SKF", "manufacturer_designation": "YAR 206-104-2F", "series": "YAR2-series", "type": "insert", "d_mm": 31.75, "D_mm": 62, "B_mm": 38.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 280, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 206-104-2F is a grub-screw insert bearing with the inner ring extended on both sides, 31.75x62x38.1 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -104 = 31.75 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 31.75x62x38.1 mm (1.25x2.441x1.5 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 280 g. Width accounting on this execution: 38.1 mm overall and 18 mm outer-ring width leave the housing designer 20.1 mm of inner-ring projection to accommodate the locking arrangement. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 31.75x62 mm insert on its chamfer tilts the whole spherical seat. Mass-to-load ratio for YAR-206-104-2F: 14.359 g of catalogue mass per rated kN of C, and 8.819 g per millimetre of bore — useful when comparing executions of the same 31.75x62 mm envelope on the drawing. Load balance for documentation: C0 11.2 kN against C 19.5 kN gives a 0.574 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Envelope arithmetic: the radial section from 31.75 mm bore to 62 mm OD is 15.125 mm; dividing C 19.5 kN by that section gives 1.289 kN per section millimetre, and the 38.1 mm overall width is 2.519x the section. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-206-104-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 15.125 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "garden and groundcare equipment", "trough conveyor idler drives" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Do not specify the 31.75 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 22.2 mm s1 dimension is the screw seating geometry inside the 20.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 206-104-2F as the grub two f execution; other order numbers of the YAR 206-104 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-206-104-2F?", "a": "The catalogue envelope is 31.75x62x38.1 mm with a spherical outside surface; mass 280 g. Ratings C 19.5/11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YAR 206-104-2F mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -104 = 31.75 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "How is YAR-206-104-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 31.75 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-206-104-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-206-104-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (19.5/11.2 kN vs 16.3/11.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-206-104", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 206-104 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-206-104-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x62x38.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 206-104-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-206-104-2F", "YAR 206-104-2F" ], "locale_variants": {} }, { "sku": "YAR-207-104-2RF-HV", "brand": "SKF", "manufacturer_designation": "YAR 207-104-2RF/HV", "series": "YAR2-series", "type": "insert", "d_mm": 31.75, "D_mm": 72, "B_mm": 42.9, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 21.6, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 207-104-2RF/HV is a grub-screw insert bearing with the inner ring extended on both sides, 31.75x72x42.9 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -104 = 31.75 mm, which is why this row sits beside, not on, the metric bore size. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed. Envelope 31.75x72x42.9 mm (1.25x2.835x1.689 in), outer ring 19 mm wide, C 21.6 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,200 r/min; mass 500 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 46.1 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Load balance for documentation: C0 15.3 kN against C 21.6 kN gives a 0.708 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Pitch-diameter arithmetic: dm = (31.75+72)/2 = 51.875 mm; at the 3,200 r/min limiting speed the ball set runs at dn approx 1.66x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. The s1 25.4 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Rating split for the maintenance file: dynamic 21.6 kN (L10), static 15.3 kN (s0 shock check), fatigue 0.655 kN (adjusted life) — three separate uses for YAR 207-104-2RF/HV, none interchangeable with another. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-207-104-2RF-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20.125 mm radial section.", "applications": [ "garden and groundcare equipment", "small packaging and labelling machines", "trough conveyor idler drives" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 31.75 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 21.6/15.3 kN figures belong specifically to YAR 207-104-2RF/HV; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-104-2RF-HV?", "a": "The catalogue envelope is 31.75x72x42.9 mm with a spherical outside surface; mass 500 g. Ratings C 21.6/15.3 kN, Pu 0.655 kN, limiting speed 3,200 r/min." }, { "q": "What does the designation YAR 207-104-2RF/HV mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -104 = 31.75 mm, which is why this row sits beside, not on, the metric bore size. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-207-104-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-104-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-207-104", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-104-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-104-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-104-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-104-2RF-HV", "YAR 207-104-2RF/HV" ], "locale_variants": {} }, { "sku": "YAR-207-104-2RFGR-HV", "brand": "SKF", "manufacturer_designation": "YAR 207-104-2RFGR/HV", "series": "YAR2-series", "type": "insert", "d_mm": 31.75, "D_mm": 72, "B_mm": 42.9, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 21.6, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 207-104-2RFGR/HV is a SKF insert bearing (Y-bearing) for a 31.75 mm (1.25 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -104 decodes as 1\" +4/16, i.e. 31.75 mm; the metric coded size YAR 207 shares the same envelope but its bore is the metric value, not this one. the HV suffix means stainless rings and balls with food-grade compliant seals and grease (this article also carries the GR outside-surface lubrication groove); capacity is derated versus the carbon-steel part. Envelope 31.75x72x42.9 mm (1.25x2.835x1.689 in), outer ring 19 mm wide, C 21.6 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,200 r/min; mass 500 g. Selection figures for YAR 207-104-2RFGR/HV: C0/C is 0.708, Pu 0.655 kN is 3.032 % of the 21.6 kN dynamic rating, and the 500 g catalogue mass works out to roughly 15.748 g per millimetre of the 31.75 mm bore. Width accounting on this execution: 42.9 mm overall and 19 mm outer-ring width leave the housing designer 23.9 mm of inner-ring projection to accommodate the locking arrangement. Grease-life arithmetic is dominated by speed: at dn approx 1.66x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Spherical-seat note in numbers: the 72 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 51.875 = 162.97 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Capacity density: 21.6 kN from 0.500 kg of bearing steel is about 43.2 kN per kilogram, and per width millimetre the 42.9 mm unit carries 0.503 kN of dynamic capacity. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Set-screw geometry on this size: the two 120 deg screws bear on the 31.75 mm shaft inside the 42.9 mm total width while the outer ring is only 19 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "small packaging and labelling machines", "trough conveyor idler drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Do not specify the 31.75 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAR 207-104-2RFGR/HV as the grub two hv execution; other order numbers of the YAR 207-104 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-104-2RFGR-HV?", "a": "Boundary dimensions: bore 31.75 mm, sphered OD 72 mm, overall width 42.9 mm; weight 500 g. Loads: dynamic 21.6 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 3,200 r/min limiting value." }, { "q": "What does the designation YAR 207-104-2RFGR/HV mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -104 decodes as 1\" +4/16, i.e. 31.75 mm; the metric coded size YAR 207 shares the same envelope but its bore is the metric value, not this one. the HV suffix means stainless rings and balls with food-grade compliant seals and grease (this article also carries the GR outside-surface lubrication groove); capacity is derated versus the carbon-steel part." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR-207-104-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-104-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-207-104", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-104-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-104-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-104-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-104-2RFGR-HV", "YAR 207-104-2RFGR/HV" ], "locale_variants": {} }, { "sku": "YARAG-207-104", "brand": "SKF", "manufacturer_designation": "YARAG 207-104", "series": "YAR2-series", "type": "insert", "d_mm": 31.75, "D_mm": 72, "B_mm": 42.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 490, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YARAG 207-104 is a grub-screw insert bearing with the inner ring extended on both sides, 31.75x72x42.9 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -104 = 31.75 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 31.75x72x42.9 mm (1.25x2.835x1.689 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,100 r/min; mass 490 g. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 31.75x72 mm insert on its chamfer tilts the whole spherical seat. Selection figures for YARAG 207-104: C0/C is 0.6, Pu 0.655 kN is 2.569 % of the 25.5 kN dynamic rating, and the 490 g catalogue mass works out to roughly 15.433 g per millimetre of the 31.75 mm bore. Pitch-diameter arithmetic: dm = (31.75+72)/2 = 51.875 mm; at the 1,100 r/min limiting speed the ball set runs at dn approx 0.57x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Load balance for documentation: C0 15.3 kN against C 25.5 kN gives a 0.6 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Rating split for the maintenance file: dynamic 25.5 kN (L10), static 15.3 kN (s0 shock check), fatigue 0.655 kN (adjusted life) — three separate uses for YARAG 207-104, none interchangeable with another. Set-screw geometry on this size: the two 120 deg screws bear on the 31.75 mm shaft inside the 42.9 mm total width while the outer ring is only 19 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "head- and tail-shaft pillow blocks in unit handling", "small packaging and labelling machines" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Do not specify the 31.75 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YARAG 207-104 as the grub two ag execution; other order numbers of the YARAG 207-104 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-207-104?", "a": "The catalogue envelope is 31.75x72x42.9 mm with a spherical outside surface; mass 490 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 1,100 r/min." }, { "q": "What does the designation YARAG 207-104 mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -104 = 31.75 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "How is YARAG-207-104 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 31.75 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-207-104-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-104-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-104-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-104-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-104-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-104-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-104-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-104-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-207-104", "YARAG 207-104" ], "locale_variants": {} }, { "sku": "YAR-207-104-2RF", "brand": "SKF", "manufacturer_designation": "YAR 207-104-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 31.75, "D_mm": 72, "B_mm": 42.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 510, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 207-104-2RF is a grub-screw insert bearing with the inner ring extended on both sides, 31.75x72x42.9 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -104 = 31.75 mm, which is why this row sits beside, not on, the metric bore size. the -2RF external design combines contact nitrile seals with rubberized additional flingers on both sides for a tighter labyrinth than the plain-flinger -2F execution. Envelope 31.75x72x42.9 mm (1.25x2.835x1.689 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,200 r/min; mass 510 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 46.1 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the rubberized flinger. Spherical-seat note in numbers: the 72 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 51.875 = 162.97 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Envelope arithmetic: the radial section from 31.75 mm bore to 72 mm OD is 20.125 mm; dividing C 25.5 kN by that section gives 1.267 kN per section millimetre, and the 42.9 mm overall width is 2.132x the section. Outer-vs-overall width: the outer ring is 19 mm wide inside the 42.9 mm total, so the extended inner ring accounts for 0.557 of the overall width (11.95 mm of axial projection per side). The s1 25.4 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Set-screw geometry on this size: the two 120 deg screws bear on the 31.75 mm shaft inside the 42.9 mm total width while the outer ring is only 19 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "trough conveyor idler drives", "small packaging and labelling machines" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 31.75 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 207-104-2RF as the grub two rf execution; other order numbers of the YAR 207-104 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-104-2RF?", "a": "The catalogue envelope is 31.75x72x42.9 mm with a spherical outside surface; mass 510 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 3,200 r/min." }, { "q": "What does the designation YAR 207-104-2RF mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -104 = 31.75 mm, which is why this row sits beside, not on, the metric bore size. the -2RF external design combines contact nitrile seals with rubberized additional flingers on both sides for a tighter labyrinth than the plain-flinger -2F execution." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-207-104-2RF lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-207-104-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-104-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-207-104", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207-104 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-104-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-104-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-104-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-104-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-104-2RF", "YAR 207-104-2RF" ], "locale_variants": {} }, { "sku": "YAR-207-104-2RF-VE495", "brand": "SKF", "manufacturer_designation": "YAR 207-104-2RF/VE495", "series": "YAR2-series", "type": "insert", "d_mm": 31.75, "D_mm": 72, "B_mm": 42.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 510, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 207-104-2RF/VE495 is a SKF insert bearing (Y-bearing) for a 31.75 mm (1.25 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -104 decodes as 1\" +4/16, i.e. 31.75 mm; the metric coded size YAR 207 shares the same envelope but its bore is the metric value, not this one. the VE495 suffix packages zinc-coated rings with stainless-reinforced food-grade seals/flingers and food-grade lubricant — the wash-down-resistant counterpart of the standard -2RF bearing. Envelope 31.75x72x42.9 mm (1.25x2.835x1.689 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,200 r/min; mass 510 g. Pitch-diameter arithmetic: dm = (31.75+72)/2 = 51.875 mm; at the 3,200 r/min limiting speed the ball set runs at dn approx 1.66x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Capacity density: 25.5 kN from 0.510 kg of bearing steel is about 50 kN per kilogram, and per width millimetre the 42.9 mm unit carries 0.594 kN of dynamic capacity. Spherical-seat note in numbers: the 72 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 51.875 = 162.97 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fatigue-limit check: Pu 0.655 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAR 207-104-2RF/VE495 — most belt-driven mounted-unit loads sit comfortably under 2.569 % of C. Mass-to-load ratio for YAR-207-104-2RF-VE495: 20 g of catalogue mass per rated kN of C, and 16.063 g per millimetre of bore — useful when comparing executions of the same 31.75x72 mm envelope on the drawing. Zinc-coated food-range note: the VE495 plating is a functional surface, not cosmetic; clean the bore and shaft WITHOUT steel brushes or aggressive descalers, mount dry or with the approved food-grade mounting paste, and touch up damaged plating spots before commissioning the wash-down area. Set-screw geometry on this size: the two 120 deg screws bear on the 31.75 mm shaft inside the 42.9 mm total width while the outer ring is only 19 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "trough conveyor idler drives", "small packaging and labelling machines" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 31.75 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 25.5/15.3 kN figures belong specifically to YAR 207-104-2RF/VE495; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-104-2RF-VE495?", "a": "Boundary dimensions: bore 31.75 mm, sphered OD 72 mm, overall width 42.9 mm; weight 510 g. Loads: dynamic 25.5 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 3,200 r/min limiting value." }, { "q": "What does the designation YAR 207-104-2RF/VE495 mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -104 decodes as 1\" +4/16, i.e. 31.75 mm; the metric coded size YAR 207 shares the same envelope but its bore is the metric value, not this one. the VE495 suffix packages zinc-coated rings with stainless-reinforced food-grade seals/flingers and food-grade lubricant — the wash-down-resistant counterpart of the standard -2RF bearing." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-207-104-2RF-VE495 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-207-104-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-104-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-207-104", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207-104 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-104-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-104-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-104-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-104-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-104-2RF-VE495", "YAR 207-104-2RF/VE495" ], "locale_variants": {} }, { "sku": "YAR-207-104-2F", "brand": "SKF", "manufacturer_designation": "YAR 207-104-2F", "series": "YAR2-series", "type": "insert", "d_mm": 31.75, "D_mm": 72, "B_mm": 42.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 207-104-2F is SKF's 31.75 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 31.75x72x42.9 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -104 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 4/16 in = 31.75 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 31.75x72x42.9 mm (1.25x2.835x1.689 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 500 g. Width accounting on this execution: 42.9 mm overall and 19 mm outer-ring width leave the housing designer 23.9 mm of inner-ring projection to accommodate the locking arrangement. At the printed limiting speed of 5,300 r/min the mean diameter dm = 51.875 mm implies dn about 2.75x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Imperial procurement cross-check: 1.25 in bore, 2.835 in OD, 1.689 in overall width; the 500 g mass converts to 0.500 kg (17.6 oz) for the bill of materials. Rating split for the maintenance file: dynamic 25.5 kN (L10), static 15.3 kN (s0 shock check), fatigue 0.655 kN (adjusted life) — three separate uses for YAR 207-104-2F, none interchangeable with another. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 31.75x72 mm insert on its chamfer tilts the whole spherical seat. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 31.75 mm shaft inside the 42.9 mm total width while the outer ring is only 19 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "trough conveyor idler drives", "head- and tail-shaft pillow blocks in unit handling", "ventilation and extraction fans" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 31.75 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Ordering discipline for the 31.75 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-104-2F?", "a": "YAR 207-104-2F measures 31.75 mm bore x 72 mm OD x 42.9 mm overall width (outer ring 19 mm wide), 1.25 x 2.835 x 1.689 in; mass about 500 g. SKF 17000 ratings: C 25.5 kN, C0 15.3 kN, Pu 0.655 kN, limiting speed 5,300 r/min." }, { "q": "What does the designation YAR 207-104-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -104 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 4/16 in = 31.75 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "How is YAR-207-104-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 31.75 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-207-104-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-104-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-207-104", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207-104 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-104-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-104-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-104-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-104-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-104-2F", "YAR 207-104-2F" ], "locale_variants": {} }, { "sku": "YAR-207-105-2F", "brand": "SKF", "manufacturer_designation": "YAR 207-105-2F", "series": "YAR2-series", "type": "insert", "d_mm": 33.3375, "D_mm": 72, "B_mm": 42.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 480, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 207-105-2F is SKF's 33.3375 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 33.3375x72x42.9 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -105 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 5/16 in = 33.337 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 33.3375x72x42.9 mm (1.313x2.835x1.689 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 480 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 46.1 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 33.3375x72 mm insert on its chamfer tilts the whole spherical seat. Load balance for documentation: C0 15.3 kN against C 25.5 kN gives a 0.6 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Pitch-diameter arithmetic: dm = (33.3375+72)/2 = 52.669 mm; at the 5,300 r/min limiting speed the ball set runs at dn approx 2.79x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Width accounting on this execution: 42.9 mm overall and 19 mm outer-ring width leave the housing designer 23.9 mm of inner-ring projection to accommodate the locking arrangement. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-207-105-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 19.331 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "small packaging and labelling machines", "garden and groundcare equipment" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Do not specify the 33.3375 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAR 207-105-2F as the grub two f execution; other order numbers of the YAR 207-105 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-105-2F?", "a": "YAR 207-105-2F measures 33.3375 mm bore x 72 mm OD x 42.9 mm overall width (outer ring 19 mm wide), 1.313 x 2.835 x 1.689 in; mass about 480 g. SKF 17000 ratings: C 25.5 kN, C0 15.3 kN, Pu 0.655 kN, limiting speed 5,300 r/min." }, { "q": "What does the designation YAR 207-105-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -105 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 5/16 in = 33.337 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "How is YAR-207-105-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 33.3375 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-105-2F", "YAR 207-105-2F" ], "locale_variants": {} }, { "sku": "YAR-207-106-2RF-HV", "brand": "SKF", "manufacturer_designation": "YAR 207-106-2RF/HV", "series": "YAR2-series", "type": "insert", "d_mm": 34.925, "D_mm": 72, "B_mm": 42.9, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 21.6, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 207-106-2RF/HV is a SKF insert bearing (Y-bearing) for a 34.925 mm (1.375 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -106 decodes as 1\" +6/16, i.e. 34.925 mm; the metric coded size YAR 207 shares the same envelope but its bore is the metric value, not this one. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part. Envelope 34.925x72x42.9 mm (1.375x2.835x1.689 in), outer ring 19 mm wide, C 21.6 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,200 r/min; mass 450 g. Static-first planning: the 0.357 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 34.925 mm shaft, not the 21.6 kN L10 value. Pitch-diameter arithmetic: dm = (34.925+72)/2 = 53.462 mm; at the 3,200 r/min limiting speed the ball set runs at dn approx 1.71x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 46.1 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Grease-life arithmetic is dominated by speed: at dn approx 1.71x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Bore-to-OD planning: OD 72 over bore 34.925 is a 2.062x step, while bore/overall-width gives 0.814; the spherical seat in the matching Y-housing must be specified to the 72 mm OD, not to a cylindrical housing bore. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Set-screw geometry on this size: the two 120 deg screws bear on the 34.925 mm shaft inside the 42.9 mm total width while the outer ring is only 19 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "trough conveyor idler drives", "head- and tail-shaft pillow blocks in unit handling" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 34.925 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 21.6/15.3 kN figures belong specifically to YAR 207-106-2RF/HV; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-106-2RF-HV?", "a": "Boundary dimensions: bore 34.925 mm, sphered OD 72 mm, overall width 42.9 mm; weight 450 g. Loads: dynamic 21.6 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 3,200 r/min limiting value." }, { "q": "What does the designation YAR 207-106-2RF/HV mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -106 decodes as 1\" +6/16, i.e. 34.925 mm; the metric coded size YAR 207 shares the same envelope but its bore is the metric value, not this one. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-207-106-2RF-HV lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-207-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-207", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-207-106", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-106-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-106-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-106-2RF-HV", "YAR 207-106-2RF/HV" ], "locale_variants": {} }, { "sku": "YAR-207-106-2RFGR-HV", "brand": "SKF", "manufacturer_designation": "YAR 207-106-2RFGR/HV", "series": "YAR2-series", "type": "insert", "d_mm": 34.925, "D_mm": 72, "B_mm": 42.9, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 21.6, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 207-106-2RFGR/HV is SKF's 34.925 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 34.925x72x42.9 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -106 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 6/16 in = 34.925 mm (first digit whole inches, next two sixteenths of an inch). /HV identifies the stainless-steel, food-industry execution: stainless bearing components, food-compatible rubber in the seal/flinger set and food-grade grease fill — the catalogue ratings are correspondingly below the standard steel version, and the GR marking adds the lubrication groove in the sphered outside surface on the locking side. Envelope 34.925x72x42.9 mm (1.375x2.835x1.689 in), outer ring 19 mm wide, C 21.6 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,200 r/min; mass 450 g. Outer-vs-overall width: the outer ring is 19 mm wide inside the 42.9 mm total, so the extended inner ring accounts for 0.557 of the overall width (11.95 mm of axial projection per side). Rating split for the maintenance file: dynamic 21.6 kN (L10), static 15.3 kN (s0 shock check), fatigue 0.655 kN (adjusted life) — three separate uses for YAR 207-106-2RFGR/HV, none interchangeable with another. Selection figures for YAR 207-106-2RFGR/HV: C0/C is 0.708, Pu 0.655 kN is 3.032 % of the 21.6 kN dynamic rating, and the 450 g catalogue mass works out to roughly 12.885 g per millimetre of the 34.925 mm bore. Static-first planning: the 0.357 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 34.925 mm shaft, not the 21.6 kN L10 value. At the printed limiting speed of 3,200 r/min the mean diameter dm = 53.462 mm implies dn about 1.71x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Set-screw geometry on this size: the two 120 deg screws bear on the 34.925 mm shaft inside the 42.9 mm total width while the outer ring is only 19 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small packaging and labelling machines", "ventilation and extraction fans", "garden and groundcare equipment" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Do not specify the 34.925 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAR 207-106-2RFGR/HV as the grub two hv execution; other order numbers of the YAR 207-106 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-106-2RFGR-HV?", "a": "YAR 207-106-2RFGR/HV measures 34.925 mm bore x 72 mm OD x 42.9 mm overall width (outer ring 19 mm wide), 1.375 x 2.835 x 1.689 in; mass about 450 g. SKF 17000 ratings: C 21.6 kN, C0 15.3 kN, Pu 0.655 kN, limiting speed 3,200 r/min." }, { "q": "What does the designation YAR 207-106-2RFGR/HV mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -106 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 6/16 in = 34.925 mm (first digit whole inches, next two sixteenths of an inch). /HV identifies the stainless-steel, food-industry execution: stainless bearing components, food-compatible rubber in the seal/flinger set and food-grade grease fill — the catalogue ratings are correspondingly below the standard steel version, and the GR marking adds the lubrication groove in the sphered outside surface on the locking side." }, { "q": "How do the set screws lock the 34.925 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-207-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-207", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-207-106", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-106-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-106-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-106-2RFGR-HV", "YAR 207-106-2RFGR/HV" ], "locale_variants": {} }, { "sku": "YARAG-207-106", "brand": "SKF", "manufacturer_designation": "YARAG 207-106", "series": "YAR2-series", "type": "insert", "d_mm": 34.925, "D_mm": 72, "B_mm": 42.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YARAG 207-106 is a SKF insert bearing (Y-bearing) for a 34.925 mm (1.375 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -106 decodes as 1\" +6/16, i.e. 34.925 mm; the metric coded size YARAG 207 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution. Envelope 34.925x72x42.9 mm (1.375x2.835x1.689 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,100 r/min; mass 440 g. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 34.925x72 mm insert on its chamfer tilts the whole spherical seat. Load balance for documentation: C0 15.3 kN against C 25.5 kN gives a 0.6 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Rating split for the maintenance file: dynamic 25.5 kN (L10), static 15.3 kN (s0 shock check), fatigue 0.655 kN (adjusted life) — three separate uses for YARAG 207-106, none interchangeable with another. Mass-to-load ratio for YARAG-207-106: 17.255 g of catalogue mass per rated kN of C, and 12.598 g per millimetre of bore — useful when comparing executions of the same 34.925x72 mm envelope on the drawing. Pitch-diameter arithmetic: dm = (34.925+72)/2 = 53.462 mm; at the 1,100 r/min limiting speed the ball set runs at dn approx 0.59x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Set-screw geometry on this size: the two 120 deg screws bear on the 34.925 mm shaft inside the 42.9 mm total width while the outer ring is only 19 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "garden and groundcare equipment", "ventilation and extraction fans" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 34.925 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 34.925 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-207-106?", "a": "Boundary dimensions: bore 34.925 mm, sphered OD 72 mm, overall width 42.9 mm; weight 440 g. Loads: dynamic 25.5 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 1,100 r/min limiting value." }, { "q": "What does the designation YARAG 207-106 mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -106 decodes as 1\" +6/16, i.e. 34.925 mm; the metric coded size YARAG 207 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-207-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-207", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-106-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-106-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-106-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-207-106", "YARAG 207-106" ], "locale_variants": {} }, { "sku": "YAR-207-106-2RF-VE495", "brand": "SKF", "manufacturer_designation": "YAR 207-106-2RF/VE495", "series": "YAR2-series", "type": "insert", "d_mm": 34.925, "D_mm": 72, "B_mm": 42.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 207-106-2RF/VE495 is a SKF insert bearing (Y-bearing) for a 34.925 mm (1.375 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -106 decodes as 1\" +6/16, i.e. 34.925 mm; the metric coded size YAR 207 shares the same envelope but its bore is the metric value, not this one. the VE495 suffix packages zinc-coated rings with stainless-reinforced food-grade seals/flingers and food-grade lubricant — the wash-down-resistant counterpart of the standard -2RF bearing. Envelope 34.925x72x42.9 mm (1.375x2.835x1.689 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,200 r/min; mass 450 g. Bore-to-OD planning: OD 72 over bore 34.925 is a 2.062x step, while bore/overall-width gives 0.814; the spherical seat in the matching Y-housing must be specified to the 72 mm OD, not to a cylindrical housing bore. Imperial procurement cross-check: 1.375 in bore, 2.835 in OD, 1.689 in overall width; the 450 g mass converts to 0.450 kg (15.9 oz) for the bill of materials. At the printed limiting speed of 3,200 r/min the mean diameter dm = 53.462 mm implies dn about 1.71x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 34.925x72 mm insert on its chamfer tilts the whole spherical seat. Capacity density: 25.5 kN from 0.450 kg of bearing steel is about 56.667 kN per kilogram, and per width millimetre the 42.9 mm unit carries 0.594 kN of dynamic capacity. Zinc-coated food-range note: the VE495 plating is a functional surface, not cosmetic; clean the bore and shaft WITHOUT steel brushes or aggressive descalers, mount dry or with the approved food-grade mounting paste, and touch up damaged plating spots before commissioning the wash-down area. Set-screw geometry on this size: the two 120 deg screws bear on the 34.925 mm shaft inside the 42.9 mm total width while the outer ring is only 19 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "garden and groundcare equipment", "head- and tail-shaft pillow blocks in unit handling", "trough conveyor idler drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 34.925 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAR 207-106-2RF/VE495 as the grub two ve495 execution; other order numbers of the YAR 207-106 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-106-2RF-VE495?", "a": "Boundary dimensions: bore 34.925 mm, sphered OD 72 mm, overall width 42.9 mm; weight 450 g. Loads: dynamic 25.5 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 3,200 r/min limiting value." }, { "q": "What does the designation YAR 207-106-2RF/VE495 mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -106 decodes as 1\" +6/16, i.e. 34.925 mm; the metric coded size YAR 207 shares the same envelope but its bore is the metric value, not this one. the VE495 suffix packages zinc-coated rings with stainless-reinforced food-grade seals/flingers and food-grade lubricant — the wash-down-resistant counterpart of the standard -2RF bearing." }, { "q": "How is YAR-207-106-2RF-VE495 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 34.925 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-207-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-207", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-106-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-207-106", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207-106 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-106-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-106-2RF-VE495", "YAR 207-106-2RF/VE495" ], "locale_variants": {} }, { "sku": "YAR-207-106-2F", "brand": "SKF", "manufacturer_designation": "YAR 207-106-2F", "series": "YAR2-series", "type": "insert", "d_mm": 34.925, "D_mm": 72, "B_mm": 42.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 207-106-2F is SKF's 34.925 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 34.925x72x42.9 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -106 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 6/16 in = 34.925 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 34.925x72x42.9 mm (1.375x2.835x1.689 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 450 g. Spherical-seat note in numbers: the 72 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 53.462 = 167.956 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Speed ceiling of 5,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Static-first planning: the 0.357 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 34.925 mm shaft, not the 25.5 kN L10 value. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 34.925x72 mm insert on its chamfer tilts the whole spherical seat. Grease-life arithmetic is dominated by speed: at dn approx 2.83x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-207-106-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 18.538 mm radial section.", "applications": [ "trough conveyor idler drives", "head- and tail-shaft pillow blocks in unit handling", "small packaging and labelling machines" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 34.925 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 25.5/15.3 kN figures belong specifically to YAR 207-106-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-106-2F?", "a": "YAR 207-106-2F measures 34.925 mm bore x 72 mm OD x 42.9 mm overall width (outer ring 19 mm wide), 1.375 x 2.835 x 1.689 in; mass about 450 g. SKF 17000 ratings: C 25.5 kN, C0 15.3 kN, Pu 0.655 kN, limiting speed 5,300 r/min." }, { "q": "What does the designation YAR 207-106-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -106 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 6/16 in = 34.925 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "How is YAR-207-106-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 34.925 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-207-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-207", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-207-106-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-106-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-207-106", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207-106 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-106-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-106-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-106-2F", "YAR 207-106-2F" ], "locale_variants": {} }, { "sku": "YAT-207-107", "brand": "SKF", "manufacturer_designation": "YAT 207-107", "series": "YAR2-series", "type": "insert", "d_mm": 36.512499999999996, "D_mm": 72, "B_mm": 33, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 360, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAT 207-107 is a SKF insert bearing (Y-bearing) for a 36.512499999999996 mm (1.438 in) shaft: grub-screw insert bearing with the inner ring extended on one side, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. inch bore code -107 decodes as 1\" +7/16, i.e. 36.512 mm; the metric coded size YAT 207 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings. Envelope 36.512499999999996x72x33 mm (1.438x2.835x1.299 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 360 g. Pitch-diameter arithmetic: dm = (36.512499999999996+72)/2 = 54.256 mm; at the 5,300 r/min limiting speed the ball set runs at dn approx 2.88x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Width accounting on this execution: 33 mm overall and 19 mm outer-ring width leave the housing designer 14 mm of inner-ring projection to accommodate the locking arrangement. Envelope arithmetic: the radial section from 36.512499999999996 mm bore to 72 mm OD is 17.744 mm; dividing C 25.5 kN by that section gives 1.437 kN per section millimetre, and the 33 mm overall width is 1.86x the section. Mass-to-load ratio for YAT-207-107: 14.118 g of catalogue mass per rated kN of C, and 9.86 g per millimetre of bore — useful when comparing executions of the same 36.512499999999996x72 mm envelope on the drawing. At the printed limiting speed of 5,300 r/min the mean diameter dm = 54.256 mm implies dn about 2.88x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Service tip for YAT-207-107: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 17.744 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "small packaging and labelling machines", "garden and groundcare equipment" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The 23.3 mm s1 dimension is the screw seating geometry inside the 14 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 36.512499999999996 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 25.5/15.3 kN figures belong specifically to YAT 207-107; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-207-107?", "a": "Boundary dimensions: bore 36.512499999999996 mm, sphered OD 72 mm, overall width 33 mm; weight 360 g. Loads: dynamic 25.5 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 5,300 r/min limiting value." }, { "q": "What does the designation YAT 207-107 mean?", "a": "reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. inch bore code -107 decodes as 1\" +7/16, i.e. 36.512 mm; the metric coded size YAT 207 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-207-107", "YAT 207-107" ], "locale_variants": {} }, { "sku": "YAR-207-107-2RF-HV", "brand": "SKF", "manufacturer_designation": "YAR 207-107-2RF/HV", "series": "YAR2-series", "type": "insert", "d_mm": 36.512499999999996, "D_mm": 72, "B_mm": 42.9, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 21.6, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 420, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 207-107-2RF/HV is a SKF insert bearing (Y-bearing) for a 36.512499999999996 mm (1.438 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -107 decodes as 1\" +7/16, i.e. 36.512 mm; the metric coded size YAR 207 shares the same envelope but its bore is the metric value, not this one. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part. Envelope 36.512499999999996x72x42.9 mm (1.438x2.835x1.689 in), outer ring 19 mm wide, C 21.6 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,200 r/min; mass 420 g. Selection figures for YAR 207-107-2RF/HV: C0/C is 0.708, Pu 0.655 kN is 3.032 % of the 21.6 kN dynamic rating, and the 420 g catalogue mass works out to roughly 11.503 g per millimetre of the 36.512499999999996 mm bore. Outer-vs-overall width: the outer ring is 19 mm wide inside the 42.9 mm total, so the extended inner ring accounts for 0.557 of the overall width (11.95 mm of axial projection per side). Rating split for the maintenance file: dynamic 21.6 kN (L10), static 15.3 kN (s0 shock check), fatigue 0.655 kN (adjusted life) — three separate uses for YAR 207-107-2RF/HV, none interchangeable with another. Load balance for documentation: C0 15.3 kN against C 21.6 kN gives a 0.708 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Speed ceiling of 3,200 r/min is the catalogue mechanical limit for THIS execution; the stainless/food-grade HV fill sets this lower value, so real fan duty is planned well below it. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Set-screw geometry on this size: the two 120 deg screws bear on the 36.512499999999996 mm shaft inside the 42.9 mm total width while the outer ring is only 19 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "garden and groundcare equipment", "trough conveyor idler drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 36.512499999999996 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Ordering discipline for the 36.512499999999996 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-107-2RF-HV?", "a": "Boundary dimensions: bore 36.512499999999996 mm, sphered OD 72 mm, overall width 42.9 mm; weight 420 g. Loads: dynamic 21.6 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 3,200 r/min limiting value." }, { "q": "What does the designation YAR 207-107-2RF/HV mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -107 decodes as 1\" +7/16, i.e. 36.512 mm; the metric coded size YAR 207 shares the same envelope but its bore is the metric value, not this one. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-207-107-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-107-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-207-107", "equiv_brand": "SKF", "level": "partial", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-107-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-107-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-107-2RF-HV", "YAR 207-107-2RF/HV" ], "locale_variants": {} }, { "sku": "YAR-207-107-2RFGR-HV", "brand": "SKF", "manufacturer_designation": "YAR 207-107-2RFGR/HV", "series": "YAR2-series", "type": "insert", "d_mm": 36.512499999999996, "D_mm": 72, "B_mm": 42.9, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 21.6, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 420, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 207-107-2RFGR/HV is a grub-screw insert bearing with the inner ring extended on both sides, 36.512499999999996x72x42.9 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -107 = 36.512 mm, which is why this row sits beside, not on, the metric bore size. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed. Envelope 36.512499999999996x72x42.9 mm (1.438x2.835x1.689 in), outer ring 19 mm wide, C 21.6 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,200 r/min; mass 420 g. Pitch-diameter arithmetic: dm = (36.512499999999996+72)/2 = 54.256 mm; at the 3,200 r/min limiting speed the ball set runs at dn approx 1.74x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Spherical-seat note in numbers: the 72 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 54.256 = 170.45 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fatigue-limit check: Pu 0.655 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAR 207-107-2RFGR/HV — most belt-driven mounted-unit loads sit comfortably under 3.032 % of C. Bore-to-OD planning: OD 72 over bore 36.512499999999996 is a 1.972x step, while bore/overall-width gives 0.851; the spherical seat in the matching Y-housing must be specified to the 72 mm OD, not to a cylindrical housing bore. Speed ceiling of 3,200 r/min is the catalogue mechanical limit for THIS execution; the stainless/food-grade HV fill sets this lower value, so real fan duty is planned well below it. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Set-screw geometry on this size: the two 120 deg screws bear on the 36.512499999999996 mm shaft inside the 42.9 mm total width while the outer ring is only 19 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "garden and groundcare equipment", "trough conveyor idler drives", "small packaging and labelling machines" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 36.512499999999996 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 21.6/15.3 kN figures belong specifically to YAR 207-107-2RFGR/HV; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-107-2RFGR-HV?", "a": "The catalogue envelope is 36.512499999999996x72x42.9 mm with a spherical outside surface; mass 420 g. Ratings C 21.6/15.3 kN, Pu 0.655 kN, limiting speed 3,200 r/min." }, { "q": "What does the designation YAR 207-107-2RFGR/HV mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -107 = 36.512 mm, which is why this row sits beside, not on, the metric bore size. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-207-107-2RFGR-HV lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-207-107-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-107-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-207-107", "equiv_brand": "SKF", "level": "partial", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-107-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-107-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (21.6/15.3 kN vs 25.5/15.3 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-107-2RFGR-HV", "YAR 207-107-2RFGR/HV" ], "locale_variants": {} }, { "sku": "YARAG-207-107", "brand": "SKF", "manufacturer_designation": "YARAG 207-107", "series": "YAR2-series", "type": "insert", "d_mm": 36.512499999999996, "D_mm": 72, "B_mm": 42.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 410, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YARAG 207-107 is a grub-screw insert bearing with the inner ring extended on both sides, 36.512499999999996x72x42.9 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -107 = 36.512 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 36.512499999999996x72x42.9 mm (1.438x2.835x1.689 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,100 r/min; mass 410 g. Selection figures for YARAG 207-107: C0/C is 0.6, Pu 0.655 kN is 2.569 % of the 25.5 kN dynamic rating, and the 410 g catalogue mass works out to roughly 11.229 g per millimetre of the 36.512499999999996 mm bore. Outer-vs-overall width: the outer ring is 19 mm wide inside the 42.9 mm total, so the extended inner ring accounts for 0.557 of the overall width (11.95 mm of axial projection per side). At the printed limiting speed of 1,100 r/min the mean diameter dm = 54.256 mm implies dn about 0.60x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Spherical-seat note in numbers: the 72 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 54.256 = 170.45 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. The s1 25.4 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Set-screw geometry on this size: the two 120 deg screws bear on the 36.512499999999996 mm shaft inside the 42.9 mm total width while the outer ring is only 19 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "garden and groundcare equipment", "trough conveyor idler drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 36.512499999999996 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YARAG 207-107 as the grub two ag execution; other order numbers of the YARAG 207-107 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-207-107?", "a": "The catalogue envelope is 36.512499999999996x72x42.9 mm with a spherical outside surface; mass 410 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 1,100 r/min." }, { "q": "What does the designation YARAG 207-107 mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -107 = 36.512 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-207-107-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-107-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-107-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-107-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-107-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-107-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-207-107", "YARAG 207-107" ], "locale_variants": {} }, { "sku": "YAR-207-107-2RF-VE495", "brand": "SKF", "manufacturer_designation": "YAR 207-107-2RF/VE495", "series": "YAR2-series", "type": "insert", "d_mm": 36.512499999999996, "D_mm": 72, "B_mm": 42.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 420, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 207-107-2RF/VE495 is a grub-screw insert bearing with the inner ring extended on both sides, 36.512499999999996x72x42.9 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -107 = 36.512 mm, which is why this row sits beside, not on, the metric bore size. VE495 denotes galvanized rings plus food-compatible sealing components and grease, aimed at humid, cleaned-down installations rather than submerged chemical duty. Envelope 36.512499999999996x72x42.9 mm (1.438x2.835x1.689 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,200 r/min; mass 420 g. Bore-to-OD planning: OD 72 over bore 36.512499999999996 is a 1.972x step, while bore/overall-width gives 0.851; the spherical seat in the matching Y-housing must be specified to the 72 mm OD, not to a cylindrical housing bore. Grease-life arithmetic is dominated by speed: at dn approx 1.74x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Spherical-seat note in numbers: the 72 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 54.256 = 170.45 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Capacity density: 25.5 kN from 0.420 kg of bearing steel is about 60.714 kN per kilogram, and per width millimetre the 42.9 mm unit carries 0.594 kN of dynamic capacity. Static-first planning: the 0.357 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 36.512499999999996 mm shaft, not the 25.5 kN L10 value. Zinc-coated food-range note: the VE495 plating is a functional surface, not cosmetic; clean the bore and shaft WITHOUT steel brushes or aggressive descalers, mount dry or with the approved food-grade mounting paste, and touch up damaged plating spots before commissioning the wash-down area. Service tip for YAR-207-107-2RF-VE495: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 17.744 mm radial section.", "applications": [ "garden and groundcare equipment", "trough conveyor idler drives", "ventilation and extraction fans" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Do not specify the 36.512499999999996 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 207-107-2RF/VE495 as the grub two ve495 execution; other order numbers of the YAR 207-107 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-107-2RF-VE495?", "a": "The catalogue envelope is 36.512499999999996x72x42.9 mm with a spherical outside surface; mass 420 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 3,200 r/min." }, { "q": "What does the designation YAR 207-107-2RF/VE495 mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -107 = 36.512 mm, which is why this row sits beside, not on, the metric bore size. VE495 denotes galvanized rings plus food-compatible sealing components and grease, aimed at humid, cleaned-down installations rather than submerged chemical duty." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-207-107-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-107-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-207-107", "equiv_brand": "SKF", "level": "full", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207-107 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-107-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-107-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-107-2RF-VE495", "YAR 207-107-2RF/VE495" ], "locale_variants": {} }, { "sku": "YAR-207-107-2F", "brand": "SKF", "manufacturer_designation": "YAR 207-107-2F", "series": "YAR2-series", "type": "insert", "d_mm": 36.512499999999996, "D_mm": 72, "B_mm": 42.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 420, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 207-107-2F is SKF's 36.512499999999996 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 36.512499999999996x72x42.9 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -107 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 7/16 in = 36.512 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 36.512499999999996x72x42.9 mm (1.438x2.835x1.689 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 420 g. Width accounting on this execution: 42.9 mm overall and 19 mm outer-ring width leave the housing designer 23.9 mm of inner-ring projection to accommodate the locking arrangement. Spherical-seat note in numbers: the 72 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 54.256 = 170.45 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Imperial procurement cross-check: 1.438 in bore, 2.835 in OD, 1.689 in overall width; the 420 g mass converts to 0.420 kg (14.8 oz) for the bill of materials. Load balance for documentation: C0 15.3 kN against C 25.5 kN gives a 0.6 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. The s1 25.4 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-207-107-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 17.744 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "trough conveyor idler drives", "garden and groundcare equipment" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 36.512499999999996 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 25.4 mm s1 dimension is the screw seating geometry inside the 23.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 36.512499999999996 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-207-107-2F?", "a": "YAR 207-107-2F measures 36.512499999999996 mm bore x 72 mm OD x 42.9 mm overall width (outer ring 19 mm wide), 1.438 x 2.835 x 1.689 in; mass about 420 g. SKF 17000 ratings: C 25.5 kN, C0 15.3 kN, Pu 0.655 kN, limiting speed 5,300 r/min." }, { "q": "What does the designation YAR 207-107-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -107 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 7/16 in = 36.512 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-207-107-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-207-107-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-207-107-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (25.5/15.3 kN vs 21.6/15.3 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-207-107", "equiv_brand": "SKF", "level": "full", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 207-107 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-207-107-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 36.512499999999996x72x42.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 207-107-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-207-107-2F", "YAR 207-107-2F" ], "locale_variants": {} }, { "sku": "YAR-208-107-2F", "brand": "SKF", "manufacturer_designation": "YAR 208-107-2F", "series": "YAR2-series", "type": "insert", "d_mm": 36.512499999999996, "D_mm": 80, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 680, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 208-107-2F is a grub-screw insert bearing with the inner ring extended on both sides, 36.512499999999996x80x49.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -107 = 36.512 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 36.512499999999996x80x49.2 mm (1.438x3.15x1.937 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,800 r/min; mass 680 g. Bore-to-OD planning: OD 80 over bore 36.512499999999996 is a 2.191x step, while bore/overall-width gives 0.742; the spherical seat in the matching Y-housing must be specified to the 80 mm OD, not to a cylindrical housing bore. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 51.8 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Spherical-seat note in numbers: the 80 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 58.256 = 183.017 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Pitch-diameter arithmetic: dm = (36.512499999999996+80)/2 = 58.256 mm; at the 4,800 r/min limiting speed the ball set runs at dn approx 2.80x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Selection figures for YAR 208-107-2F: C0/C is 0.619, Pu 0.8 kN is 2.606 % of the 30.7 kN dynamic rating, and the 680 g catalogue mass works out to roughly 18.624 g per millimetre of the 36.512499999999996 mm bore. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-208-107-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 21.744 mm radial section.", "applications": [ "ventilation and extraction fans", "trough conveyor idler drives", "small packaging and labelling machines" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 36.512499999999996 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 30.2 mm s1 dimension is the screw seating geometry inside the 28.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 208-107-2F as the grub two f execution; other order numbers of the YAR 208-107 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-208-107-2F?", "a": "The catalogue envelope is 36.512499999999996x80x49.2 mm with a spherical outside surface; mass 680 g. Ratings C 30.7/19 kN, Pu 0.8 kN, limiting speed 4,800 r/min." }, { "q": "What does the designation YAR 208-107-2F mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -107 = 36.512 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-208-107-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-208-107-2F", "YAR 208-107-2F" ], "locale_variants": {} }, { "sku": "YAT-208-108", "brand": "SKF", "manufacturer_designation": "YAT 208-108", "series": "YAR2-series", "type": "insert", "d_mm": 38.099999999999994, "D_mm": 80, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 530, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAT 208-108 is a SKF insert bearing (Y-bearing) for a 38.099999999999994 mm (1.5 in) shaft: grub-screw insert bearing with the inner ring extended on one side, built to the ISO 15 diameter-series envelope with a sphered OD of 80 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. inch bore code -108 decodes as 1\" +8/16, i.e. 38.1 mm; the metric coded size YAT 208 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings. Envelope 38.099999999999994x80x36 mm (1.5x3.15x1.417 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,800 r/min; mass 530 g. Grease-life arithmetic is dominated by speed: at dn approx 2.83x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Width accounting on this execution: 36 mm overall and 21 mm outer-ring width leave the housing designer 15 mm of inner-ring projection to accommodate the locking arrangement. Load balance for documentation: C0 19 kN against C 30.7 kN gives a 0.619 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Rating split for the maintenance file: dynamic 30.7 kN (L10), static 19 kN (s0 shock check), fatigue 0.8 kN (adjusted life) — three separate uses for YAT 208-108, none interchangeable with another. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 38.099999999999994x80 mm insert on its chamfer tilts the whole spherical seat. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Set-screw geometry on this size: the two 120 deg screws bear on the 38.099999999999994 mm shaft inside the 36 mm total width while the outer ring is only 21 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "small packaging and labelling machines", "garden and groundcare equipment" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Do not specify the 38.099999999999994 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 25.3 mm s1 dimension is the screw seating geometry inside the 15 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAT 208-108 as the grub one open execution; other order numbers of the YAT 208-108 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-208-108?", "a": "Boundary dimensions: bore 38.099999999999994 mm, sphered OD 80 mm, overall width 36 mm; weight 530 g. Loads: dynamic 30.7 kN, static 19 kN, fatigue 0.8 kN; the only published speed is the 4,800 r/min limiting value." }, { "q": "What does the designation YAT 208-108 mean?", "a": "reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. inch bore code -108 decodes as 1\" +8/16, i.e. 38.1 mm; the metric coded size YAT 208 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-208-108", "YAT 208-108" ], "locale_variants": {} }, { "sku": "YAR-208-108-2RF-HV", "brand": "SKF", "manufacturer_designation": "YAR 208-108-2RF/HV", "series": "YAR2-series", "type": "insert", "d_mm": 38.099999999999994, "D_mm": 80, "B_mm": 49.2, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 24.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 208-108-2RF/HV is a grub-screw insert bearing with the inner ring extended on both sides, 38.099999999999994x80x49.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -108 = 38.1 mm, which is why this row sits beside, not on, the metric bore size. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed. Envelope 38.099999999999994x80x49.2 mm (1.5x3.15x1.937 in), outer ring 21 mm wide, C 24.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,800 r/min; mass 650 g. Load balance for documentation: C0 19 kN against C 24.7 kN gives a 0.769 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Speed ceiling of 2,800 r/min is the catalogue mechanical limit for THIS execution; the stainless/food-grade HV fill sets this lower value, so real fan duty is planned well below it. Imperial procurement cross-check: 1.5 in bore, 3.15 in OD, 1.937 in overall width; the 650 g mass converts to 0.650 kg (22.9 oz) for the bill of materials. Bore-to-OD planning: OD 80 over bore 38.099999999999994 is a 2.1x step, while bore/overall-width gives 0.774; the spherical seat in the matching Y-housing must be specified to the 80 mm OD, not to a cylindrical housing bore. Rating split for the maintenance file: dynamic 24.7 kN (L10), static 19 kN (s0 shock check), fatigue 0.8 kN (adjusted life) — three separate uses for YAR 208-108-2RF/HV, none interchangeable with another. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-208-108-2RF-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20.95 mm radial section.", "applications": [ "garden and groundcare equipment", "head- and tail-shaft pillow blocks in unit handling", "trough conveyor idler drives" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 38.099999999999994 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 30.2 mm s1 dimension is the screw seating geometry inside the 28.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 38.099999999999994 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-208-108-2RF-HV?", "a": "The catalogue envelope is 38.099999999999994x80x49.2 mm with a spherical outside surface; mass 650 g. Ratings C 24.7/19 kN, Pu 0.8 kN, limiting speed 2,800 r/min." }, { "q": "What does the designation YAR 208-108-2RF/HV mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -108 = 38.1 mm, which is why this row sits beside, not on, the metric bore size. HV is the corrosion-resistant food-range variant of the -2RF sealed design — stainless parts plus food-compatible rubber and lubricant, which also explains its lower published C and limiting speed." }, { "q": "How is YAR-208-108-2RF-HV lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 38.099999999999994 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-208-108-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-108-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-208-108", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-108-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-108-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-108-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-208-108-2RF-HV", "YAR 208-108-2RF/HV" ], "locale_variants": {} }, { "sku": "YAR-208-108-2RFGR-HV", "brand": "SKF", "manufacturer_designation": "YAR 208-108-2RFGR/HV", "series": "YAR2-series", "type": "insert", "d_mm": 38.099999999999994, "D_mm": 80, "B_mm": 49.2, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 24.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 208-108-2RFGR/HV is a SKF insert bearing (Y-bearing) for a 38.099999999999994 mm (1.5 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 80 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -108 decodes as 1\" +8/16, i.e. 38.1 mm; the metric coded size YAR 208 shares the same envelope but its bore is the metric value, not this one. the HV suffix means stainless rings and balls with food-grade compliant seals and grease (this article also carries the GR outside-surface lubrication groove); capacity is derated versus the carbon-steel part. Envelope 38.099999999999994x80x49.2 mm (1.5x3.15x1.937 in), outer ring 21 mm wide, C 24.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,800 r/min; mass 650 g. Outer-vs-overall width: the outer ring is 21 mm wide inside the 49.2 mm total, so the extended inner ring accounts for 0.573 of the overall width (14.1 mm of axial projection per side). Static-first planning: the 0.386 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 38.099999999999994 mm shaft, not the 24.7 kN L10 value. Load balance for documentation: C0 19 kN against C 24.7 kN gives a 0.769 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Grease-life arithmetic is dominated by speed: at dn approx 1.65x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Bore-to-OD planning: OD 80 over bore 38.099999999999994 is a 2.1x step, while bore/overall-width gives 0.774; the spherical seat in the matching Y-housing must be specified to the 80 mm OD, not to a cylindrical housing bore. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-208-108-2RFGR-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20.95 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "small packaging and labelling machines", "garden and groundcare equipment" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Do not specify the 38.099999999999994 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 30.2 mm s1 dimension is the screw seating geometry inside the 28.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 208-108-2RFGR/HV as the grub two hv execution; other order numbers of the YAR 208-108 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-208-108-2RFGR-HV?", "a": "Boundary dimensions: bore 38.099999999999994 mm, sphered OD 80 mm, overall width 49.2 mm; weight 650 g. Loads: dynamic 24.7 kN, static 19 kN, fatigue 0.8 kN; the only published speed is the 2,800 r/min limiting value." }, { "q": "What does the designation YAR 208-108-2RFGR/HV mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -108 decodes as 1\" +8/16, i.e. 38.1 mm; the metric coded size YAR 208 shares the same envelope but its bore is the metric value, not this one. the HV suffix means stainless rings and balls with food-grade compliant seals and grease (this article also carries the GR outside-surface lubrication groove); capacity is derated versus the carbon-steel part." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR-208-108-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-108-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-208-108", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-108-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-108-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-108-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (24.7/19 kN vs 30.7/19 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-208-108-2RFGR-HV", "YAR 208-108-2RFGR/HV" ], "locale_variants": {} }, { "sku": "YARAG-208-108", "brand": "SKF", "manufacturer_designation": "YARAG 208-108", "series": "YAR2-series", "type": "insert", "d_mm": 38.099999999999994, "D_mm": 80, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 950, "max_rpm": 950, "weight_g": 630, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YARAG 208-108 is SKF's 38.099999999999994 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 38.099999999999994x80x49.2 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -108 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 8/16 in = 38.1 mm (first digit whole inches, next two sixteenths of an inch). AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant. Envelope 38.099999999999994x80x49.2 mm (1.5x3.15x1.937 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 950 r/min; mass 630 g. Spherical-seat note in numbers: the 80 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 59.05 = 185.511 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Capacity density: 30.7 kN from 0.630 kg of bearing steel is about 48.73 kN per kilogram, and per width millimetre the 49.2 mm unit carries 0.624 kN of dynamic capacity. Imperial procurement cross-check: 1.5 in bore, 3.15 in OD, 1.937 in overall width; the 630 g mass converts to 0.630 kg (22.2 oz) for the bill of materials. Mass-to-load ratio for YARAG-208-108: 20.521 g of catalogue mass per rated kN of C, and 16.535 g per millimetre of bore — useful when comparing executions of the same 38.099999999999994x80 mm envelope on the drawing. Grease-life arithmetic is dominated by speed: at dn approx 0.56x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the AG variant caps speed so aggressively, and high-temperature mounts shorten both even when load is light. Service tip for YARAG-208-108: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20.95 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "trough conveyor idler drives", "small packaging and labelling machines" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 38.099999999999994 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 30.2 mm s1 dimension is the screw seating geometry inside the 28.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YARAG 208-108 as the grub two ag execution; other order numbers of the YARAG 208-108 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-208-108?", "a": "YARAG 208-108 measures 38.099999999999994 mm bore x 80 mm OD x 49.2 mm overall width (outer ring 21 mm wide), 1.5 x 3.15 x 1.937 in; mass about 630 g. SKF 17000 ratings: C 30.7 kN, C0 19 kN, Pu 0.8 kN, limiting speed 950 r/min." }, { "q": "What does the designation YARAG 208-108 mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -108 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 8/16 in = 38.1 mm (first digit whole inches, next two sixteenths of an inch). AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YARAG-208-108 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-208-108-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-108-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-108-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-108-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-108-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-108-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-108-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-108-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-208-108", "YARAG 208-108" ], "locale_variants": {} }, { "sku": "YAR-208-108-2RF", "brand": "SKF", "manufacturer_designation": "YAR 208-108-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 38.099999999999994, "D_mm": 80, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 208-108-2RF is a SKF insert bearing (Y-bearing) for a 38.099999999999994 mm (1.5 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 80 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -108 decodes as 1\" +8/16, i.e. 38.1 mm; the metric coded size YAR 208 shares the same envelope but its bore is the metric value, not this one. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments. Envelope 38.099999999999994x80x49.2 mm (1.5x3.15x1.937 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,800 r/min; mass 650 g. Spherical-seat note in numbers: the 80 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 59.05 = 185.511 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Speed ceiling of 2,800 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Mass-to-load ratio for YAR-208-108-2RF: 21.173 g of catalogue mass per rated kN of C, and 17.06 g per millimetre of bore — useful when comparing executions of the same 38.099999999999994x80 mm envelope on the drawing. Selection figures for YAR 208-108-2RF: C0/C is 0.619, Pu 0.8 kN is 2.606 % of the 30.7 kN dynamic rating, and the 650 g catalogue mass works out to roughly 17.06 g per millimetre of the 38.099999999999994 mm bore. Imperial procurement cross-check: 1.5 in bore, 3.15 in OD, 1.937 in overall width; the 650 g mass converts to 0.650 kg (22.9 oz) for the bill of materials. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Set-screw geometry on this size: the two 120 deg screws bear on the 38.099999999999994 mm shaft inside the 49.2 mm total width while the outer ring is only 21 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "trough conveyor idler drives", "small packaging and labelling machines" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 38.099999999999994 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 30.2 mm s1 dimension is the screw seating geometry inside the 28.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAR 208-108-2RF as the grub two rf execution; other order numbers of the YAR 208-108 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-208-108-2RF?", "a": "Boundary dimensions: bore 38.099999999999994 mm, sphered OD 80 mm, overall width 49.2 mm; weight 650 g. Loads: dynamic 30.7 kN, static 19 kN, fatigue 0.8 kN; the only published speed is the 2,800 r/min limiting value." }, { "q": "What does the designation YAR 208-108-2RF mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -108 decodes as 1\" +8/16, i.e. 38.1 mm; the metric coded size YAR 208 shares the same envelope but its bore is the metric value, not this one. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-208-108-2RF lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-208-108-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-108-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-208-108", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 208-108 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-108-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-108-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-108-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-108-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-208-108-2RF", "YAR 208-108-2RF" ], "locale_variants": {} }, { "sku": "YAR-208-108-2RF-VE495", "brand": "SKF", "manufacturer_designation": "YAR 208-108-2RF/VE495", "series": "YAR2-series", "type": "insert", "d_mm": 38.099999999999994, "D_mm": 80, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 208-108-2RF/VE495 is a grub-screw insert bearing with the inner ring extended on both sides, 38.099999999999994x80x49.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -108 = 38.1 mm, which is why this row sits beside, not on, the metric bore size. VE495 denotes galvanized rings plus food-compatible sealing components and grease, aimed at humid, cleaned-down installations rather than submerged chemical duty. Envelope 38.099999999999994x80x49.2 mm (1.5x3.15x1.937 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,800 r/min; mass 650 g. Fatigue-limit check: Pu 0.8 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAR 208-108-2RF/VE495 — most belt-driven mounted-unit loads sit comfortably under 2.606 % of C. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 51.8 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Grease-life arithmetic is dominated by speed: at dn approx 1.65x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Static-first planning: the 0.386 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 38.099999999999994 mm shaft, not the 30.7 kN L10 value. Bore-to-OD planning: OD 80 over bore 38.099999999999994 is a 2.1x step, while bore/overall-width gives 0.774; the spherical seat in the matching Y-housing must be specified to the 80 mm OD, not to a cylindrical housing bore. Zinc-coated food-range note: the VE495 plating is a functional surface, not cosmetic; clean the bore and shaft WITHOUT steel brushes or aggressive descalers, mount dry or with the approved food-grade mounting paste, and touch up damaged plating spots before commissioning the wash-down area. Set-screw geometry on this size: the two 120 deg screws bear on the 38.099999999999994 mm shaft inside the 49.2 mm total width while the outer ring is only 21 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small packaging and labelling machines", "trough conveyor idler drives", "head- and tail-shaft pillow blocks in unit handling" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Do not specify the 38.099999999999994 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 30.2 mm s1 dimension is the screw seating geometry inside the 28.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 208-108-2RF/VE495 as the grub two ve495 execution; other order numbers of the YAR 208-108 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-208-108-2RF-VE495?", "a": "The catalogue envelope is 38.099999999999994x80x49.2 mm with a spherical outside surface; mass 650 g. Ratings C 30.7/19 kN, Pu 0.8 kN, limiting speed 2,800 r/min." }, { "q": "What does the designation YAR 208-108-2RF/VE495 mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -108 = 38.1 mm, which is why this row sits beside, not on, the metric bore size. VE495 denotes galvanized rings plus food-compatible sealing components and grease, aimed at humid, cleaned-down installations rather than submerged chemical duty." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-208-108-2RF-VE495 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-208-108-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-108-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-208-108", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 208-108 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-108-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-108-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-108-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-108-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-208-108-2RF-VE495", "YAR 208-108-2RF/VE495" ], "locale_variants": {} }, { "sku": "YAR-208-108-2F", "brand": "SKF", "manufacturer_designation": "YAR 208-108-2F", "series": "YAR2-series", "type": "insert", "d_mm": 38.099999999999994, "D_mm": 80, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 208-108-2F is a SKF insert bearing (Y-bearing) for a 38.099999999999994 mm (1.5 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 80 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -108 decodes as 1\" +8/16, i.e. 38.1 mm; the metric coded size YAR 208 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 38.099999999999994x80x49.2 mm (1.5x3.15x1.937 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,800 r/min; mass 650 g. Outer-vs-overall width: the outer ring is 21 mm wide inside the 49.2 mm total, so the extended inner ring accounts for 0.573 of the overall width (14.1 mm of axial projection per side). Imperial procurement cross-check: 1.5 in bore, 3.15 in OD, 1.937 in overall width; the 650 g mass converts to 0.650 kg (22.9 oz) for the bill of materials. Load balance for documentation: C0 19 kN against C 30.7 kN gives a 0.619 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Rating split for the maintenance file: dynamic 30.7 kN (L10), static 19 kN (s0 shock check), fatigue 0.8 kN (adjusted life) — three separate uses for YAR 208-108-2F, none interchangeable with another. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 38.099999999999994x80 mm insert on its chamfer tilts the whole spherical seat. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-208-108-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20.95 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "garden and groundcare equipment", "trough conveyor idler drives" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 38.099999999999994 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 30.2 mm s1 dimension is the screw seating geometry inside the 28.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 38.099999999999994 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-208-108-2F?", "a": "Boundary dimensions: bore 38.099999999999994 mm, sphered OD 80 mm, overall width 49.2 mm; weight 650 g. Loads: dynamic 30.7 kN, static 19 kN, fatigue 0.8 kN; the only published speed is the 4,800 r/min limiting value." }, { "q": "What does the designation YAR 208-108-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -108 decodes as 1\" +8/16, i.e. 38.1 mm; the metric coded size YAR 208 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "How is YAR-208-108-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 38.099999999999994 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-208-108-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-208-108-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-208-108", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 208-108 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-108-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-108-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-208-108-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-108-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-208-108-2F", "YAR 208-108-2F" ], "locale_variants": {} }, { "sku": "YAR-209-108-2F", "brand": "SKF", "manufacturer_designation": "YAR 209-108-2F", "series": "YAR2-series", "type": "insert", "d_mm": 38.099999999999994, "D_mm": 85, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 840, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 209-108-2F is SKF's 38.099999999999994 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 38.099999999999994x85x49.2 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -108 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 8/16 in = 38.1 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 38.099999999999994x85x49.2 mm (1.5x3.346x1.937 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 840 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 56.8 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Capacity density: 33.2 kN from 0.840 kg of bearing steel is about 39.524 kN per kilogram, and per width millimetre the 49.2 mm unit carries 0.675 kN of dynamic capacity. Selection figures for YAR 209-108-2F: C0/C is 0.651, Pu 0.915 kN is 2.756 % of the 33.2 kN dynamic rating, and the 840 g catalogue mass works out to roughly 22.047 g per millimetre of the 38.099999999999994 mm bore. Imperial procurement cross-check: 1.5 in bore, 3.346 in OD, 1.937 in overall width; the 840 g mass converts to 0.840 kg (29.6 oz) for the bill of materials. Speed ceiling of 4,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 38.099999999999994 mm shaft inside the 49.2 mm total width while the outer ring is only 22 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "trough conveyor idler drives", "small packaging and labelling machines", "ventilation and extraction fans" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "The 30.2 mm s1 dimension is the screw seating geometry inside the 27.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 38.099999999999994 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 33.2/21.6 kN figures belong specifically to YAR 209-108-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-209-108-2F?", "a": "YAR 209-108-2F measures 38.099999999999994 mm bore x 85 mm OD x 49.2 mm overall width (outer ring 22 mm wide), 1.5 x 3.346 x 1.937 in; mass about 840 g. SKF 17000 ratings: C 33.2 kN, C0 21.6 kN, Pu 0.915 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YAR 209-108-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -108 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 8/16 in = 38.1 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-209-108-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-209-108-2F", "YAR 209-108-2F" ], "locale_variants": {} }, { "sku": "YAR-208-109-2F", "brand": "SKF", "manufacturer_designation": "YAR 208-109-2F", "series": "YAR2-series", "type": "insert", "d_mm": 39.6875, "D_mm": 80, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 610, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 208-109-2F is SKF's 39.6875 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 39.6875x80x49.2 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -109 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 9/16 in = 39.688 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 39.6875x80x49.2 mm (1.563x3.15x1.937 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,800 r/min; mass 610 g. Selection figures for YAR 208-109-2F: C0/C is 0.619, Pu 0.8 kN is 2.606 % of the 30.7 kN dynamic rating, and the 610 g catalogue mass works out to roughly 15.37 g per millimetre of the 39.6875 mm bore. Rating split for the maintenance file: dynamic 30.7 kN (L10), static 19 kN (s0 shock check), fatigue 0.8 kN (adjusted life) — three separate uses for YAR 208-109-2F, none interchangeable with another. Static-first planning: the 0.386 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 39.6875 mm shaft, not the 30.7 kN L10 value. Capacity density: 30.7 kN from 0.610 kg of bearing steel is about 50.328 kN per kilogram, and per width millimetre the 49.2 mm unit carries 0.624 kN of dynamic capacity. Grease-life arithmetic is dominated by speed: at dn approx 2.87x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 39.6875 mm shaft inside the 49.2 mm total width while the outer ring is only 21 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small packaging and labelling machines", "ventilation and extraction fans", "trough conveyor idler drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 39.6875 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 30.2 mm s1 dimension is the screw seating geometry inside the 28.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 39.6875 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-208-109-2F?", "a": "YAR 208-109-2F measures 39.6875 mm bore x 80 mm OD x 49.2 mm overall width (outer ring 21 mm wide), 1.563 x 3.15 x 1.937 in; mass about 610 g. SKF 17000 ratings: C 30.7 kN, C0 19 kN, Pu 0.8 kN, limiting speed 4,800 r/min." }, { "q": "What does the designation YAR 208-109-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -109 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 9/16 in = 39.688 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "How do the set screws lock the 39.6875 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-208-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 39.6875x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 39.6875 mm vs 40 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-208-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 39.6875x80x49.2 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (30.7/19 kN vs 24.7/19 kN) — envelope match, not a load-rating equivalent. NOTE the bore differs: 39.6875 mm vs 40 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YARAG-208", "equiv_brand": "SKF", "level": "full", "note": "Same 39.6875x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 208 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 39.6875 mm vs 40 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-208-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 39.6875x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 39.6875 mm vs 40 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-208-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 39.6875x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 39.6875 mm vs 40 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YAR-208-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 39.6875x80x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 208-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 39.6875 mm vs 40 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-208-109-2F", "YAR 208-109-2F" ], "locale_variants": {} }, { "sku": "YARAG-209-110", "brand": "SKF", "manufacturer_designation": "YARAG 209-110", "series": "YAR2-series", "type": "insert", "d_mm": 41.275, "D_mm": 85, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 850, "max_rpm": 850, "weight_g": 750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YARAG 209-110 is a SKF insert bearing (Y-bearing) for a 41.275 mm (1.625 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 85 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -110 decodes as 1\" +10/16, i.e. 41.275 mm; the metric coded size YARAG 209 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution. Envelope 41.275x85x49.2 mm (1.625x3.346x1.937 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 850 r/min; mass 750 g. At the printed limiting speed of 850 r/min the mean diameter dm = 63.138 mm implies dn about 0.54x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 56.8 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Rating split for the maintenance file: dynamic 33.2 kN (L10), static 21.6 kN (s0 shock check), fatigue 0.915 kN (adjusted life) — three separate uses for YARAG 209-110, none interchangeable with another. Imperial procurement cross-check: 1.625 in bore, 3.346 in OD, 1.937 in overall width; the 750 g mass converts to 0.750 kg (26.5 oz) for the bill of materials. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 41.275x85 mm insert on its chamfer tilts the whole spherical seat. Set-screw geometry on this size: the two 120 deg screws bear on the 41.275 mm shaft inside the 49.2 mm total width while the outer ring is only 22 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "trough conveyor idler drives", "ventilation and extraction fans", "small packaging and labelling machines" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 41.275 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 30.2 mm s1 dimension is the screw seating geometry inside the 27.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 41.275 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-209-110?", "a": "Boundary dimensions: bore 41.275 mm, sphered OD 85 mm, overall width 49.2 mm; weight 750 g. Loads: dynamic 33.2 kN, static 21.6 kN, fatigue 0.915 kN; the only published speed is the 850 r/min limiting value." }, { "q": "What does the designation YARAG 209-110 mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -110 decodes as 1\" +10/16, i.e. 41.275 mm; the metric coded size YARAG 209 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YARAG-209-110 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-209-110-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 41.275x85x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 209-110-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-209-110", "YARAG 209-110" ], "locale_variants": {} }, { "sku": "YAR-209-110-2F", "brand": "SKF", "manufacturer_designation": "YAR 209-110-2F", "series": "YAR2-series", "type": "insert", "d_mm": 41.275, "D_mm": 85, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 770, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 209-110-2F is a SKF insert bearing (Y-bearing) for a 41.275 mm (1.625 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 85 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -110 decodes as 1\" +10/16, i.e. 41.275 mm; the metric coded size YAR 209 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 41.275x85x49.2 mm (1.625x3.346x1.937 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 770 g. Rating split for the maintenance file: dynamic 33.2 kN (L10), static 21.6 kN (s0 shock check), fatigue 0.915 kN (adjusted life) — three separate uses for YAR 209-110-2F, none interchangeable with another. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 41.275x85 mm insert on its chamfer tilts the whole spherical seat. The s1 30.2 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Spherical-seat note in numbers: the 85 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 63.138 = 198.354 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Envelope arithmetic: the radial section from 41.275 mm bore to 85 mm OD is 21.863 mm; dividing C 33.2 kN by that section gives 1.519 kN per section millimetre, and the 49.2 mm overall width is 2.25x the section. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-209-110-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 21.863 mm radial section.", "applications": [ "ventilation and extraction fans", "head- and tail-shaft pillow blocks in unit handling", "trough conveyor idler drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "The 30.2 mm s1 dimension is the screw seating geometry inside the 27.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 41.275 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 33.2/21.6 kN figures belong specifically to YAR 209-110-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-209-110-2F?", "a": "Boundary dimensions: bore 41.275 mm, sphered OD 85 mm, overall width 49.2 mm; weight 770 g. Loads: dynamic 33.2 kN, static 21.6 kN, fatigue 0.915 kN; the only published speed is the 4,300 r/min limiting value." }, { "q": "What does the designation YAR 209-110-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -110 decodes as 1\" +10/16, i.e. 41.275 mm; the metric coded size YAR 209 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "How is YAR-209-110-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 41.275 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YARAG-209-110", "equiv_brand": "SKF", "level": "full", "note": "Same 41.275x85x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 209-110 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-209-110-2F", "YAR 209-110-2F" ], "locale_variants": {} }, { "sku": "YAT-209-111", "brand": "SKF", "manufacturer_designation": "YAT 209-111", "series": "YAR2-series", "type": "insert", "d_mm": 42.8625, "D_mm": 85, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 610, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAT 209-111 is a SKF insert bearing (Y-bearing) for a 42.8625 mm (1.688 in) shaft: grub-screw insert bearing with the inner ring extended on one side, built to the ISO 15 diameter-series envelope with a sphered OD of 85 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. inch bore code -111 decodes as 1\" +11/16, i.e. 42.862 mm; the metric coded size YAT 209 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings. Envelope 42.8625x85x37 mm (1.688x3.346x1.457 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 610 g. Grease-life arithmetic is dominated by speed: at dn approx 2.75x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Bore-to-OD planning: OD 85 over bore 42.8625 is a 1.983x step, while bore/overall-width gives 1.158; the spherical seat in the matching Y-housing must be specified to the 85 mm OD, not to a cylindrical housing bore. Imperial procurement cross-check: 1.688 in bore, 3.346 in OD, 1.457 in overall width; the 610 g mass converts to 0.610 kg (21.5 oz) for the bill of materials. Mass-to-load ratio for YAT-209-111: 18.373 g of catalogue mass per rated kN of C, and 14.232 g per millimetre of bore — useful when comparing executions of the same 42.8625x85 mm envelope on the drawing. Selection figures for YAT 209-111: C0/C is 0.651, Pu 0.915 kN is 2.756 % of the 33.2 kN dynamic rating, and the 610 g catalogue mass works out to roughly 14.232 g per millimetre of the 42.8625 mm bore. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Service tip for YAT-209-111: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 21.069 mm radial section.", "applications": [ "trough conveyor idler drives", "ventilation and extraction fans", "garden and groundcare equipment" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "The 25.8 mm s1 dimension is the screw seating geometry inside the 15 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 42.8625 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 33.2/21.6 kN figures belong specifically to YAT 209-111; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-209-111?", "a": "Boundary dimensions: bore 42.8625 mm, sphered OD 85 mm, overall width 37 mm; weight 610 g. Loads: dynamic 33.2 kN, static 21.6 kN, fatigue 0.915 kN; the only published speed is the 4,300 r/min limiting value." }, { "q": "What does the designation YAT 209-111 mean?", "a": "reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. inch bore code -111 decodes as 1\" +11/16, i.e. 42.862 mm; the metric coded size YAT 209 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings." }, { "q": "How do the set screws lock the 42.8625 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-209-111", "YAT 209-111" ], "locale_variants": {} }, { "sku": "YARAG-209-111", "brand": "SKF", "manufacturer_designation": "YARAG 209-111", "series": "YAR2-series", "type": "insert", "d_mm": 42.8625, "D_mm": 85, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 850, "max_rpm": 850, "weight_g": 710, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YARAG 209-111 is a grub-screw insert bearing with the inner ring extended on both sides, 42.8625x85x49.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -111 = 42.862 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 42.8625x85x49.2 mm (1.688x3.346x1.937 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 850 r/min; mass 710 g. Load balance for documentation: C0 21.6 kN against C 33.2 kN gives a 0.651 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Pitch-diameter arithmetic: dm = (42.8625+85)/2 = 63.931 mm; at the 850 r/min limiting speed the ball set runs at dn approx 0.54x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Grease-life arithmetic is dominated by speed: at dn approx 0.54x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the AG variant caps speed so aggressively, and high-temperature mounts shorten both even when load is light. Envelope arithmetic: the radial section from 42.8625 mm bore to 85 mm OD is 21.069 mm; dividing C 33.2 kN by that section gives 1.576 kN per section millimetre, and the 49.2 mm overall width is 2.335x the section. The s1 30.2 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Set-screw geometry on this size: the two 120 deg screws bear on the 42.8625 mm shaft inside the 49.2 mm total width while the outer ring is only 22 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small packaging and labelling machines", "trough conveyor idler drives", "garden and groundcare equipment" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "The 30.2 mm s1 dimension is the screw seating geometry inside the 27.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 42.8625 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 33.2/21.6 kN figures belong specifically to YARAG 209-111; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-209-111?", "a": "The catalogue envelope is 42.8625x85x49.2 mm with a spherical outside surface; mass 710 g. Ratings C 33.2/21.6 kN, Pu 0.915 kN, limiting speed 850 r/min." }, { "q": "What does the designation YARAG 209-111 mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -111 = 42.862 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YARAG-209-111 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-209-111-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 42.8625x85x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 209-111-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-209-111", "YARAG 209-111" ], "locale_variants": {} }, { "sku": "YAR-209-111-2F", "brand": "SKF", "manufacturer_designation": "YAR 209-111-2F", "series": "YAR2-series", "type": "insert", "d_mm": 42.8625, "D_mm": 85, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 730, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 209-111-2F is a grub-screw insert bearing with the inner ring extended on both sides, 42.8625x85x49.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -111 = 42.862 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 42.8625x85x49.2 mm (1.688x3.346x1.937 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 730 g. Spherical-seat note in numbers: the 85 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 63.931 = 200.845 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Grease-life arithmetic is dominated by speed: at dn approx 2.75x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 42.8625x85 mm insert on its chamfer tilts the whole spherical seat. Pitch-diameter arithmetic: dm = (42.8625+85)/2 = 63.931 mm; at the 4,300 r/min limiting speed the ball set runs at dn approx 2.75x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Speed ceiling of 4,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-209-111-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 21.069 mm radial section.", "applications": [ "ventilation and extraction fans", "garden and groundcare equipment", "small packaging and labelling machines" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "The 30.2 mm s1 dimension is the screw seating geometry inside the 27.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 42.8625 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 33.2/21.6 kN figures belong specifically to YAR 209-111-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-209-111-2F?", "a": "The catalogue envelope is 42.8625x85x49.2 mm with a spherical outside surface; mass 730 g. Ratings C 33.2/21.6 kN, Pu 0.915 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YAR 209-111-2F mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -111 = 42.862 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YARAG-209-111", "equiv_brand": "SKF", "level": "full", "note": "Same 42.8625x85x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 209-111 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-209-111-2F", "YAR 209-111-2F" ], "locale_variants": {} }, { "sku": "YAT-209-112", "brand": "SKF", "manufacturer_designation": "YAT 209-112", "series": "YAR2-series", "type": "insert", "d_mm": 44.449999999999996, "D_mm": 85, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 580, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAT 209-112 is a grub-screw insert bearing with the inner ring extended on one side, 44.449999999999996x85x37 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -112 = 44.45 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 44.449999999999996x85x37 mm (1.75x3.346x1.457 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 580 g. Mass-to-load ratio for YAT-209-112: 17.47 g of catalogue mass per rated kN of C, and 13.048 g per millimetre of bore — useful when comparing executions of the same 44.449999999999996x85 mm envelope on the drawing. Width accounting on this execution: 37 mm overall and 22 mm outer-ring width leave the housing designer 15 mm of inner-ring projection to accommodate the locking arrangement. Pitch-diameter arithmetic: dm = (44.449999999999996+85)/2 = 64.725 mm; at the 4,300 r/min limiting speed the ball set runs at dn approx 2.78x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. At the printed limiting speed of 4,300 r/min the mean diameter dm = 64.725 mm implies dn about 2.78x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Load balance for documentation: C0 21.6 kN against C 33.2 kN gives a 0.651 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Service tip for YAT-209-112: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20.275 mm radial section.", "applications": [ "ventilation and extraction fans", "small packaging and labelling machines", "garden and groundcare equipment" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 44.449999999999996 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 25.8 mm s1 dimension is the screw seating geometry inside the 15 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAT 209-112 as the grub one open execution; other order numbers of the YAT 209-112 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-209-112?", "a": "The catalogue envelope is 44.449999999999996x85x37 mm with a spherical outside surface; mass 580 g. Ratings C 33.2/21.6 kN, Pu 0.915 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YAT 209-112 mean?", "a": "YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -112 = 44.45 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-209-112", "YAT 209-112" ], "locale_variants": {} }, { "sku": "YAR-209-112-2RF", "brand": "SKF", "manufacturer_designation": "YAR 209-112-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 44.449999999999996, "D_mm": 85, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 690, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 209-112-2RF is a grub-screw insert bearing with the inner ring extended on both sides, 44.449999999999996x85x49.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -112 = 44.45 mm, which is why this row sits beside, not on, the metric bore size. the -2RF external design combines contact nitrile seals with rubberized additional flingers on both sides for a tighter labyrinth than the plain-flinger -2F execution. Envelope 44.449999999999996x85x49.2 mm (1.75x3.346x1.937 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,400 r/min; mass 690 g. Speed ceiling of 2,400 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. The s1 30.2 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Load balance for documentation: C0 21.6 kN against C 33.2 kN gives a 0.651 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. At the printed limiting speed of 2,400 r/min the mean diameter dm = 64.725 mm implies dn about 1.55x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Pitch-diameter arithmetic: dm = (44.449999999999996+85)/2 = 64.725 mm; at the 2,400 r/min limiting speed the ball set runs at dn approx 1.55x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Service tip for YAR-209-112-2RF: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20.275 mm radial section.", "applications": [ "garden and groundcare equipment", "ventilation and extraction fans", "trough conveyor idler drives" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 44.449999999999996 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 30.2 mm s1 dimension is the screw seating geometry inside the 27.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 44.449999999999996 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-209-112-2RF?", "a": "The catalogue envelope is 44.449999999999996x85x49.2 mm with a spherical outside surface; mass 690 g. Ratings C 33.2/21.6 kN, Pu 0.915 kN, limiting speed 2,400 r/min." }, { "q": "What does the designation YAR 209-112-2RF mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -112 = 44.45 mm, which is why this row sits beside, not on, the metric bore size. the -2RF external design combines contact nitrile seals with rubberized additional flingers on both sides for a tighter labyrinth than the plain-flinger -2F execution." }, { "q": "How do the set screws lock the 44.449999999999996 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-209-112-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 44.449999999999996x85x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 209-112-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-209-112-2RF", "YAR 209-112-2RF" ], "locale_variants": {} }, { "sku": "YAR-209-112-2F", "brand": "SKF", "manufacturer_designation": "YAR 209-112-2F", "series": "YAR2-series", "type": "insert", "d_mm": 44.449999999999996, "D_mm": 85, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 690, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 209-112-2F is SKF's 44.449999999999996 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 44.449999999999996x85x49.2 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -112 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 12/16 in = 44.45 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 44.449999999999996x85x49.2 mm (1.75x3.346x1.937 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 690 g. Grease-life arithmetic is dominated by speed: at dn approx 2.78x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Spherical-seat note in numbers: the 85 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 64.725 = 203.34 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Pitch-diameter arithmetic: dm = (44.449999999999996+85)/2 = 64.725 mm; at the 4,300 r/min limiting speed the ball set runs at dn approx 2.78x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Load balance for documentation: C0 21.6 kN against C 33.2 kN gives a 0.651 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Rating split for the maintenance file: dynamic 33.2 kN (L10), static 21.6 kN (s0 shock check), fatigue 0.915 kN (adjusted life) — three separate uses for YAR 209-112-2F, none interchangeable with another. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-209-112-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20.275 mm radial section.", "applications": [ "ventilation and extraction fans", "trough conveyor idler drives", "garden and groundcare equipment" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 44.449999999999996 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 30.2 mm s1 dimension is the screw seating geometry inside the 27.2 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 44.449999999999996 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-209-112-2F?", "a": "YAR 209-112-2F measures 44.449999999999996 mm bore x 85 mm OD x 49.2 mm overall width (outer ring 22 mm wide), 1.75 x 3.346 x 1.937 in; mass about 690 g. SKF 17000 ratings: C 33.2 kN, C0 21.6 kN, Pu 0.915 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YAR 209-112-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -112 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 12/16 in = 44.45 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-209-112-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-209-112-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 44.449999999999996x85x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 209-112-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-209-112-2F", "YAR 209-112-2F" ], "locale_variants": {} }, { "sku": "YAT-210-115", "brand": "SKF", "manufacturer_designation": "YAT 210-115", "series": "YAR2-series", "type": "insert", "d_mm": 49.2125, "D_mm": 90, "B_mm": 38.8, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAT 210-115 is SKF's 49.2125 mm-bore grub-screw insert bearing with the inner ring extended on one side in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 49.2125x90x38.8 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAT prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring is extended on one side only. the three-digit -115 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 15/16 in = 49.212 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 38.8 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals. Envelope 49.2125x90x38.8 mm (1.938x3.543x1.528 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,000 r/min; mass 650 g. Width accounting on this execution: 38.8 mm overall and 22 mm outer-ring width leave the housing designer 16.8 mm of inner-ring projection to accommodate the locking arrangement. Load balance for documentation: C0 23.2 kN against C 35.1 kN gives a 0.661 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. The s1 27.6 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Rating split for the maintenance file: dynamic 35.1 kN (L10), static 23.2 kN (s0 shock check), fatigue 0.98 kN (adjusted life) — three separate uses for YAT 210-115, none interchangeable with another. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 49.2125x90 mm insert on its chamfer tilts the whole spherical seat. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Service tip for YAT-210-115: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20.394 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "garden and groundcare equipment", "trough conveyor idler drives" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The 27.6 mm s1 dimension is the screw seating geometry inside the 16.8 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 49.2125 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 35.1/23.2 kN figures belong specifically to YAT 210-115; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-210-115?", "a": "YAT 210-115 measures 49.2125 mm bore x 90 mm OD x 38.8 mm overall width (outer ring 22 mm wide), 1.938 x 3.543 x 1.528 in; mass about 650 g. SKF 17000 ratings: C 35.1 kN, C0 23.2 kN, Pu 0.98 kN, limiting speed 4,000 r/min." }, { "q": "What does the designation YAT 210-115 mean?", "a": "the YAT prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring is extended on one side only. the three-digit -115 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 15/16 in = 49.212 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 38.8 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-210-115", "YAT 210-115" ], "locale_variants": {} }, { "sku": "YAR-210-115-2RF-HV", "brand": "SKF", "manufacturer_designation": "YAR 210-115-2RF/HV", "series": "YAR2-series", "type": "insert", "d_mm": 49.2125, "D_mm": 90, "B_mm": 51.6, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 29.6, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 790, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 210-115-2RF/HV is a SKF insert bearing (Y-bearing) for a 49.2125 mm (1.938 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 90 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -115 decodes as 1\" +15/16, i.e. 49.212 mm; the metric coded size YAR 210 shares the same envelope but its bore is the metric value, not this one. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part. Envelope 49.2125x90x51.6 mm (1.938x3.543x2.031 in), outer ring 22 mm wide, C 29.6 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,200 r/min; mass 790 g. At the printed limiting speed of 2,200 r/min the mean diameter dm = 69.606 mm implies dn about 1.53x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Bore-to-OD planning: OD 90 over bore 49.2125 is a 1.829x step, while bore/overall-width gives 0.954; the spherical seat in the matching Y-housing must be specified to the 90 mm OD, not to a cylindrical housing bore. Imperial procurement cross-check: 1.938 in bore, 3.543 in OD, 2.031 in overall width; the 790 g mass converts to 0.790 kg (27.9 oz) for the bill of materials. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 49.2125x90 mm insert on its chamfer tilts the whole spherical seat. Capacity density: 29.6 kN from 0.790 kg of bearing steel is about 37.468 kN per kilogram, and per width millimetre the 51.6 mm unit carries 0.574 kN of dynamic capacity. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-210-115-2RF-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20.394 mm radial section.", "applications": [ "trough conveyor idler drives", "ventilation and extraction fans", "small packaging and labelling machines" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 49.2125 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 32.6 mm s1 dimension is the screw seating geometry inside the 29.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 49.2125 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-210-115-2RF-HV?", "a": "Boundary dimensions: bore 49.2125 mm, sphered OD 90 mm, overall width 51.6 mm; weight 790 g. Loads: dynamic 29.6 kN, static 23.2 kN, fatigue 0.98 kN; the only published speed is the 2,200 r/min limiting value." }, { "q": "What does the designation YAR 210-115-2RF/HV mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -115 decodes as 1\" +15/16, i.e. 49.212 mm; the metric coded size YAR 210 shares the same envelope but its bore is the metric value, not this one. the HV suffix means stainless rings and balls with food-grade compliant seals and grease; capacity is derated versus the carbon-steel part." }, { "q": "How do the set screws lock the 49.2125 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-210-115-2RFGR-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-115-2RFGR/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-210-115", "equiv_brand": "SKF", "level": "partial", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (29.6/23.2 kN vs 35.1/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-115-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (29.6/23.2 kN vs 35.1/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-115-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (29.6/23.2 kN vs 35.1/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-115-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (29.6/23.2 kN vs 35.1/23.2 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-210-115-2RF-HV", "YAR 210-115-2RF/HV" ], "locale_variants": {} }, { "sku": "YAR-210-115-2RFGR-HV", "brand": "SKF", "manufacturer_designation": "YAR 210-115-2RFGR/HV", "series": "YAR2-series", "type": "insert", "d_mm": 49.2125, "D_mm": 90, "B_mm": 51.6, "material": "SS440C", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 29.6, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 790, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 210-115-2RFGR/HV is a SKF insert bearing (Y-bearing) for a 49.2125 mm (1.938 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 90 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -115 decodes as 1\" +15/16, i.e. 49.212 mm; the metric coded size YAR 210 shares the same envelope but its bore is the metric value, not this one. the HV suffix means stainless rings and balls with food-grade compliant seals and grease (this article also carries the GR outside-surface lubrication groove); capacity is derated versus the carbon-steel part. Envelope 49.2125x90x51.6 mm (1.938x3.543x2.031 in), outer ring 22 mm wide, C 29.6 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,200 r/min; mass 790 g. Bore-to-OD planning: OD 90 over bore 49.2125 is a 1.829x step, while bore/overall-width gives 0.954; the spherical seat in the matching Y-housing must be specified to the 90 mm OD, not to a cylindrical housing bore. Rating split for the maintenance file: dynamic 29.6 kN (L10), static 23.2 kN (s0 shock check), fatigue 0.98 kN (adjusted life) — three separate uses for YAR 210-115-2RFGR/HV, none interchangeable with another. Spherical-seat note in numbers: the 90 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 69.606 = 218.674 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Mass-to-load ratio for YAR-210-115-2RFGR-HV: 26.689 g of catalogue mass per rated kN of C, and 16.053 g per millimetre of bore — useful when comparing executions of the same 49.2125x90 mm envelope on the drawing. Width accounting on this execution: 51.6 mm overall and 22 mm outer-ring width leave the housing designer 29.6 mm of inner-ring projection to accommodate the locking arrangement. Stainless food-range note: HV parts trade some capacity for corrosion resistance and food-compatible lubrication, and the printed limiting speed is set for that fill; do not top up with ordinary mineral grease in service — mixing greases can harden the food-grade fill and seize the seals. Service tip for YAR-210-115-2RFGR-HV: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20.394 mm radial section.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "ventilation and extraction fans", "trough conveyor idler drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Do not specify the 49.2125 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 32.6 mm s1 dimension is the screw seating geometry inside the 29.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 210-115-2RFGR/HV as the grub two hv execution; other order numbers of the YAR 210-115 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-210-115-2RFGR-HV?", "a": "Boundary dimensions: bore 49.2125 mm, sphered OD 90 mm, overall width 51.6 mm; weight 790 g. Loads: dynamic 29.6 kN, static 23.2 kN, fatigue 0.98 kN; the only published speed is the 2,200 r/min limiting value." }, { "q": "What does the designation YAR 210-115-2RFGR/HV mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -115 decodes as 1\" +15/16, i.e. 49.212 mm; the metric coded size YAR 210 shares the same envelope but its bore is the metric value, not this one. the HV suffix means stainless rings and balls with food-grade compliant seals and grease (this article also carries the GR outside-surface lubrication groove); capacity is derated versus the carbon-steel part." }, { "q": "How do the set screws lock the 49.2125 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-210-115-2RF-HV", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-115-2RF/HV is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YARAG-210-115", "equiv_brand": "SKF", "level": "partial", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (29.6/23.2 kN vs 35.1/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-115-2RF", "equiv_brand": "SKF", "level": "partial", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (29.6/23.2 kN vs 35.1/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-115-2RF-VE495", "equiv_brand": "SKF", "level": "partial", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (29.6/23.2 kN vs 35.1/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-115-2F", "equiv_brand": "SKF", "level": "partial", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (29.6/23.2 kN vs 35.1/23.2 kN) — envelope match, not a load-rating equivalent." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-210-115-2RFGR-HV", "YAR 210-115-2RFGR/HV" ], "locale_variants": {} }, { "sku": "YARAG-210-115", "brand": "SKF", "manufacturer_designation": "YARAG 210-115", "series": "YAR2-series", "type": "insert", "d_mm": 49.2125, "D_mm": 90, "B_mm": 51.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 800, "max_rpm": 800, "weight_g": 770, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YARAG 210-115 is a grub-screw insert bearing with the inner ring extended on both sides, 49.2125x90x51.6 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -115 = 49.212 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 49.2125x90x51.6 mm (1.938x3.543x2.031 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 800 r/min; mass 770 g. Rating split for the maintenance file: dynamic 35.1 kN (L10), static 23.2 kN (s0 shock check), fatigue 0.98 kN (adjusted life) — three separate uses for YARAG 210-115, none interchangeable with another. The s1 32.6 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Bore-to-OD planning: OD 90 over bore 49.2125 is a 1.829x step, while bore/overall-width gives 0.954; the spherical seat in the matching Y-housing must be specified to the 90 mm OD, not to a cylindrical housing bore. Static-first planning: the 0.45 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 49.2125 mm shaft, not the 35.1 kN L10 value. Spherical-seat note in numbers: the 90 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 69.606 = 218.674 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Service tip for YARAG-210-115: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20.394 mm radial section.", "applications": [ "small packaging and labelling machines", "ventilation and extraction fans", "trough conveyor idler drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "The 32.6 mm s1 dimension is the screw seating geometry inside the 29.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 49.2125 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 35.1/23.2 kN figures belong specifically to YARAG 210-115; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YARAG-210-115?", "a": "The catalogue envelope is 49.2125x90x51.6 mm with a spherical outside surface; mass 770 g. Ratings C 35.1/23.2 kN, Pu 0.98 kN, limiting speed 800 r/min." }, { "q": "What does the designation YARAG 210-115 mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -115 = 49.212 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "How do the set screws lock the 49.2125 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAR-210-115-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (35.1/23.2 kN vs 29.6/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-115-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (35.1/23.2 kN vs 29.6/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-115-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-115-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-210-115-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-115-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-210-115-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-115-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YARAG-210-115", "YARAG 210-115" ], "locale_variants": {} }, { "sku": "YAR-210-115-2RF", "brand": "SKF", "manufacturer_designation": "YAR 210-115-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 49.2125, "D_mm": 90, "B_mm": 51.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 790, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 210-115-2RF is SKF's 49.2125 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 49.2125x90x51.6 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -115 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 15/16 in = 49.212 mm (first digit whole inches, next two sixteenths of an inch). suffix -2RF upgrades the -2F package with a RUBBERIZED flinger on each side — the coated thrower closes the radial gap against fine dust and slurry better than the plain steel flinger of -2F. Envelope 49.2125x90x51.6 mm (1.938x3.543x2.031 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,200 r/min; mass 790 g. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 49.2125x90 mm insert on its chamfer tilts the whole spherical seat. Capacity density: 35.1 kN from 0.790 kg of bearing steel is about 44.43 kN per kilogram, and per width millimetre the 51.6 mm unit carries 0.68 kN of dynamic capacity. Bore-to-OD planning: OD 90 over bore 49.2125 is a 1.829x step, while bore/overall-width gives 0.954; the spherical seat in the matching Y-housing must be specified to the 90 mm OD, not to a cylindrical housing bore. Rating split for the maintenance file: dynamic 35.1 kN (L10), static 23.2 kN (s0 shock check), fatigue 0.98 kN (adjusted life) — three separate uses for YAR 210-115-2RF, none interchangeable with another. Static-first planning: the 0.45 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 49.2125 mm shaft, not the 35.1 kN L10 value. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Service tip for YAR-210-115-2RF: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 20.394 mm radial section.", "applications": [ "trough conveyor idler drives", "ventilation and extraction fans", "small packaging and labelling machines" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 32.6 mm s1 dimension is the screw seating geometry inside the 29.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 49.2125 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Ordering discipline for the 49.2125 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-210-115-2RF?", "a": "YAR 210-115-2RF measures 49.2125 mm bore x 90 mm OD x 51.6 mm overall width (outer ring 22 mm wide), 1.938 x 3.543 x 2.031 in; mass about 790 g. SKF 17000 ratings: C 35.1 kN, C0 23.2 kN, Pu 0.98 kN, limiting speed 2,200 r/min." }, { "q": "What does the designation YAR 210-115-2RF mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -115 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 15/16 in = 49.212 mm (first digit whole inches, next two sixteenths of an inch). suffix -2RF upgrades the -2F package with a RUBBERIZED flinger on each side — the coated thrower closes the radial gap against fine dust and slurry better than the plain steel flinger of -2F." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-210-115-2RF lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-210-115-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (35.1/23.2 kN vs 29.6/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-115-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (35.1/23.2 kN vs 29.6/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-210-115", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 210-115 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-210-115-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-115-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-210-115-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-115-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-210-115-2RF", "YAR 210-115-2RF" ], "locale_variants": {} }, { "sku": "YAR-210-115-2RF-VE495", "brand": "SKF", "manufacturer_designation": "YAR 210-115-2RF/VE495", "series": "YAR2-series", "type": "insert", "d_mm": 49.2125, "D_mm": 90, "B_mm": 51.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 790, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 210-115-2RF/VE495 is SKF's 49.2125 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 49.2125x90x51.6 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -115 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 15/16 in = 49.212 mm (first digit whole inches, next two sixteenths of an inch). /VE495 is the zinc-plated food-industry execution: zinc-coated inner and outer rings, seals and flingers with stainless-steel inserts in food-compatible rubber, and food-grade grease fill. Envelope 49.2125x90x51.6 mm (1.938x3.543x2.031 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,200 r/min; mass 790 g. Mass-to-load ratio for YAR-210-115-2RF-VE495: 22.507 g of catalogue mass per rated kN of C, and 16.053 g per millimetre of bore — useful when comparing executions of the same 49.2125x90 mm envelope on the drawing. Imperial procurement cross-check: 1.938 in bore, 3.543 in OD, 2.031 in overall width; the 790 g mass converts to 0.790 kg (27.9 oz) for the bill of materials. At the printed limiting speed of 2,200 r/min the mean diameter dm = 69.606 mm implies dn about 1.53x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Bore-to-OD planning: OD 90 over bore 49.2125 is a 1.829x step, while bore/overall-width gives 0.954; the spherical seat in the matching Y-housing must be specified to the 90 mm OD, not to a cylindrical housing bore. Speed ceiling of 2,200 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Zinc-coated food-range note: the VE495 plating is a functional surface, not cosmetic; clean the bore and shaft WITHOUT steel brushes or aggressive descalers, mount dry or with the approved food-grade mounting paste, and touch up damaged plating spots before commissioning the wash-down area. Set-screw geometry on this size: the two 120 deg screws bear on the 49.2125 mm shaft inside the 51.6 mm total width while the outer ring is only 22 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "garden and groundcare equipment", "head- and tail-shaft pillow blocks in unit handling", "trough conveyor idler drives" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Do not specify the 49.2125 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 32.6 mm s1 dimension is the screw seating geometry inside the 29.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAR 210-115-2RF/VE495 as the grub two ve495 execution; other order numbers of the YAR 210-115 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-210-115-2RF-VE495?", "a": "YAR 210-115-2RF/VE495 measures 49.2125 mm bore x 90 mm OD x 51.6 mm overall width (outer ring 22 mm wide), 1.938 x 3.543 x 2.031 in; mass about 790 g. SKF 17000 ratings: C 35.1 kN, C0 23.2 kN, Pu 0.98 kN, limiting speed 2,200 r/min." }, { "q": "What does the designation YAR 210-115-2RF/VE495 mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -115 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 15/16 in = 49.212 mm (first digit whole inches, next two sixteenths of an inch). /VE495 is the zinc-plated food-industry execution: zinc-coated inner and outer rings, seals and flingers with stainless-steel inserts in food-compatible rubber, and food-grade grease fill." }, { "q": "How is YAR-210-115-2RF-VE495 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 49.2125 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-210-115-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (35.1/23.2 kN vs 29.6/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-115-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (35.1/23.2 kN vs 29.6/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-210-115", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 210-115 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-210-115-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-115-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-210-115-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-115-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-210-115-2RF-VE495", "YAR 210-115-2RF/VE495" ], "locale_variants": {} }, { "sku": "YAR-210-115-2F", "brand": "SKF", "manufacturer_designation": "YAR 210-115-2F", "series": "YAR2-series", "type": "insert", "d_mm": 49.2125, "D_mm": 90, "B_mm": 51.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 790, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 210-115-2F is SKF's 49.2125 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 49.2125x90x51.6 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -115 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 15/16 in = 49.212 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 49.2125x90x51.6 mm (1.938x3.543x2.031 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,000 r/min; mass 790 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 62.5 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Width accounting on this execution: 51.6 mm overall and 22 mm outer-ring width leave the housing designer 29.6 mm of inner-ring projection to accommodate the locking arrangement. Speed ceiling of 4,000 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Static-first planning: the 0.45 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 49.2125 mm shaft, not the 35.1 kN L10 value. Selection figures for YAR 210-115-2F: C0/C is 0.661, Pu 0.98 kN is 2.792 % of the 35.1 kN dynamic rating, and the 790 g catalogue mass works out to roughly 16.053 g per millimetre of the 49.2125 mm bore. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 49.2125 mm shaft inside the 51.6 mm total width while the outer ring is only 22 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "small packaging and labelling machines", "head- and tail-shaft pillow blocks in unit handling", "garden and groundcare equipment" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 32.6 mm s1 dimension is the screw seating geometry inside the 29.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 49.2125 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Ordering discipline for the 49.2125 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-210-115-2F?", "a": "YAR 210-115-2F measures 49.2125 mm bore x 90 mm OD x 51.6 mm overall width (outer ring 22 mm wide), 1.938 x 3.543 x 2.031 in; mass about 790 g. SKF 17000 ratings: C 35.1 kN, C0 23.2 kN, Pu 0.98 kN, limiting speed 4,000 r/min." }, { "q": "What does the designation YAR 210-115-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -115 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 15/16 in = 49.212 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR-210-115-2RF-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (35.1/23.2 kN vs 29.6/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YAR-210-115-2RFGR-HV", "equiv_brand": "SKF", "level": "partial", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope, but catalogue C/C0 differ between executions (35.1/23.2 kN vs 29.6/23.2 kN) — envelope match, not a load-rating equivalent." }, { "equiv_sku": "YARAG-210-115", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YARAG 210-115 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-210-115-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-115-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-210-115-2RF-VE495", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x51.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 210-115-2RF/VE495 is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-210-115-2F", "YAR 210-115-2F" ], "locale_variants": {} }, { "sku": "YAT-211-200", "brand": "SKF", "manufacturer_designation": "YAT 211-200", "series": "YAR2-series", "type": "insert", "d_mm": 50.8, "D_mm": 100, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 1000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAT 211-200 is a SKF insert bearing (Y-bearing) for a 50.8 mm (2 in) shaft: grub-screw insert bearing with the inner ring extended on one side, built to the ISO 15 diameter-series envelope with a sphered OD of 100 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. inch bore code -200 decodes as 2\", i.e. 50.8 mm; the metric coded size YAT 211 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings. Envelope 50.8x100x45 mm (2x3.937x1.772 in), outer ring 25 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,600 r/min; mass 1000 g. The s1 32.5 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Spherical-seat note in numbers: the 100 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 75.4 = 236.876 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Capacity density: 43.6 kN from 1.000 kg of bearing steel is about 43.6 kN per kilogram, and per width millimetre the 45 mm unit carries 0.969 kN of dynamic capacity. Pitch-diameter arithmetic: dm = (50.8+100)/2 = 75.4 mm; at the 3,600 r/min limiting speed the ball set runs at dn approx 2.71x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Bore-to-OD planning: OD 100 over bore 50.8 is a 1.969x step, while bore/overall-width gives 1.129; the spherical seat in the matching Y-housing must be specified to the 100 mm OD, not to a cylindrical housing bore. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Set-screw geometry on this size: the two 120 deg screws bear on the 50.8 mm shaft inside the 45 mm total width while the outer ring is only 25 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "ventilation and extraction fans", "trough conveyor idler drives", "small packaging and labelling machines" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "The 32.5 mm s1 dimension is the screw seating geometry inside the 20 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 50.8 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 43.6/29 kN figures belong specifically to YAT 211-200; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-211-200?", "a": "Boundary dimensions: bore 50.8 mm, sphered OD 100 mm, overall width 45 mm; weight 1000 g. Loads: dynamic 43.6 kN, static 29 kN, fatigue 1.25 kN; the only published speed is the 3,600 r/min limiting value." }, { "q": "What does the designation YAT 211-200 mean?", "a": "reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. inch bore code -200 decodes as 2\", i.e. 50.8 mm; the metric coded size YAT 211 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAT-211-200 lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-211-200", "YAT 211-200" ], "locale_variants": {} }, { "sku": "YAR-211-200-2RF", "brand": "SKF", "manufacturer_designation": "YAR 211-200-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 50.8, "D_mm": 100, "B_mm": 55.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 1900, "max_rpm": 1900, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 211-200-2RF is a SKF insert bearing (Y-bearing) for a 50.8 mm (2 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 100 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -200 decodes as 2\", i.e. 50.8 mm; the metric coded size YAR 211 shares the same envelope but its bore is the metric value, not this one. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments. Envelope 50.8x100x55.6 mm (2x3.937x2.189 in), outer ring 25 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,900 r/min; mass 1200 g. Imperial procurement cross-check: 2 in bore, 3.937 in OD, 2.189 in overall width; the 1200 g mass converts to 1.200 kg (42.3 oz) for the bill of materials. Width accounting on this execution: 55.6 mm overall and 25 mm outer-ring width leave the housing designer 30.6 mm of inner-ring projection to accommodate the locking arrangement. Load balance for documentation: C0 29 kN against C 43.6 kN gives a 0.665 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Pitch-diameter arithmetic: dm = (50.8+100)/2 = 75.4 mm; at the 1,900 r/min limiting speed the ball set runs at dn approx 1.43x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Fatigue-limit check: Pu 1.25 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAR 211-200-2RF — most belt-driven mounted-unit loads sit comfortably under 2.867 % of C. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Service tip for YAR-211-200-2RF: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 24.6 mm radial section.", "applications": [ "ventilation and extraction fans", "small packaging and labelling machines", "head- and tail-shaft pillow blocks in unit handling" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The 33.4 mm s1 dimension is the screw seating geometry inside the 30.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 50.8 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 43.6/29 kN figures belong specifically to YAR 211-200-2RF; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-211-200-2RF?", "a": "Boundary dimensions: bore 50.8 mm, sphered OD 100 mm, overall width 55.6 mm; weight 1200 g. Loads: dynamic 43.6 kN, static 29 kN, fatigue 1.25 kN; the only published speed is the 1,900 r/min limiting value." }, { "q": "What does the designation YAR 211-200-2RF mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -200 decodes as 2\", i.e. 50.8 mm; the metric coded size YAR 211 shares the same envelope but its bore is the metric value, not this one. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR-211-200-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 50.8x100x55.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 211-200-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-211-200-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 50.8x100x55.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 211-200-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-211-200-2RF", "YAR 211-200-2RF" ], "locale_variants": {} }, { "sku": "YAR-211-200-2F", "brand": "SKF", "manufacturer_designation": "YAR 211-200-2F", "series": "YAR2-series", "type": "insert", "d_mm": 50.8, "D_mm": 100, "B_mm": 55.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 211-200-2F is SKF's 50.8 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 50.8x100x55.6 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -200 tail codes the bore in inches for inch-shaft bearings: 2 whole inch = 50.8 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 50.8x100x55.6 mm (2x3.937x2.189 in), outer ring 25 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,600 r/min; mass 1200 g. At the printed limiting speed of 3,600 r/min the mean diameter dm = 75.4 mm implies dn about 2.71x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Speed ceiling of 3,600 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Outer-vs-overall width: the outer ring is 25 mm wide inside the 55.6 mm total, so the extended inner ring accounts for 0.55 of the overall width (15.3 mm of axial projection per side). Load balance for documentation: C0 29 kN against C 43.6 kN gives a 0.665 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Spherical-seat note in numbers: the 100 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 75.4 = 236.876 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 50.8 mm shaft inside the 55.6 mm total width while the outer ring is only 25 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "head- and tail-shaft pillow blocks in unit handling", "ventilation and extraction fans", "garden and groundcare equipment" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "The 33.4 mm s1 dimension is the screw seating geometry inside the 30.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 50.8 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 43.6/29 kN figures belong specifically to YAR 211-200-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-211-200-2F?", "a": "YAR 211-200-2F measures 50.8 mm bore x 100 mm OD x 55.6 mm overall width (outer ring 25 mm wide), 2 x 3.937 x 2.189 in; mass about 1200 g. SKF 17000 ratings: C 43.6 kN, C0 29 kN, Pu 1.25 kN, limiting speed 3,600 r/min." }, { "q": "What does the designation YAR 211-200-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -200 tail codes the bore in inches for inch-shaft bearings: 2 whole inch = 50.8 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "How is YAR-211-200-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 50.8 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR-211-200-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 50.8x100x55.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 211-200-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-211-200-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 50.8x100x55.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 211-200-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-211-200-2F", "YAR 211-200-2F" ], "locale_variants": {} }, { "sku": "YAR-211-203-2F", "brand": "SKF", "manufacturer_designation": "YAR 211-203-2F", "series": "YAR2-series", "type": "insert", "d_mm": 55.5625, "D_mm": 100, "B_mm": 55.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 1000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 211-203-2F is a SKF insert bearing (Y-bearing) for a 55.5625 mm (2.188 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 100 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -203 decodes as 2\" +3/16, i.e. 55.563 mm; the metric coded size YAR 211 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 55.5625x100x55.6 mm (2.188x3.937x2.189 in), outer ring 25 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,600 r/min; mass 1000 g. Imperial procurement cross-check: 2.188 in bore, 3.937 in OD, 2.189 in overall width; the 1000 g mass converts to 1.000 kg (35.3 oz) for the bill of materials. Pitch-diameter arithmetic: dm = (55.5625+100)/2 = 77.781 mm; at the 3,600 r/min limiting speed the ball set runs at dn approx 2.80x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Fatigue-limit check: Pu 1.25 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAR 211-203-2F — most belt-driven mounted-unit loads sit comfortably under 2.867 % of C. Bore-to-OD planning: OD 100 over bore 55.5625 is a 1.8x step, while bore/overall-width gives 0.999; the spherical seat in the matching Y-housing must be specified to the 100 mm OD, not to a cylindrical housing bore. Load balance for documentation: C0 29 kN against C 43.6 kN gives a 0.665 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 55.5625 mm shaft inside the 55.6 mm total width while the outer ring is only 25 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "bulk-handling conveyor drives", "heavy fan and heater units", "agricultural harvesting machinery" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "The 33.4 mm s1 dimension is the screw seating geometry inside the 30.6 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 55.5625 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 43.6/29 kN figures belong specifically to YAR 211-203-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-211-203-2F?", "a": "Boundary dimensions: bore 55.5625 mm, sphered OD 100 mm, overall width 55.6 mm; weight 1000 g. Loads: dynamic 43.6 kN, static 29 kN, fatigue 1.25 kN; the only published speed is the 3,600 r/min limiting value." }, { "q": "What does the designation YAR 211-203-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -203 decodes as 2\" +3/16, i.e. 55.563 mm; the metric coded size YAR 211 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-211-203-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YEL-211-203-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 55.5625x100x55.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 211-203-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-211-203-2F", "YAR 211-203-2F" ], "locale_variants": {} }, { "sku": "YAR-212-203-2F", "brand": "SKF", "manufacturer_designation": "YAR 212-203-2F", "series": "YAR2-series", "type": "insert", "d_mm": 55.5625, "D_mm": 110, "B_mm": 65.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 36, "fatigue_load_limit_kN": 1.53, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 212-203-2F is a SKF insert bearing (Y-bearing) for a 55.5625 mm (2.188 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 110 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -203 decodes as 2\" +3/16, i.e. 55.563 mm; the metric coded size YAR 212 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 55.5625x110x65.1 mm (2.188x4.331x2.563 in), outer ring 26 mm wide, C 52.7 kN, C0 36 kN, Pu 1.53 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,400 r/min; mass 1600 g. Grease-life arithmetic is dominated by speed: at dn approx 2.81x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Outer-vs-overall width: the outer ring is 26 mm wide inside the 65.1 mm total, so the extended inner ring accounts for 0.601 of the overall width (19.55 mm of axial projection per side). Selection figures for YAR 212-203-2F: C0/C is 0.683, Pu 1.53 kN is 2.903 % of the 52.7 kN dynamic rating, and the 1600 g catalogue mass works out to roughly 28.796 g per millimetre of the 55.5625 mm bore. Load balance for documentation: C0 36 kN against C 52.7 kN gives a 0.683 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Imperial procurement cross-check: 2.188 in bore, 4.331 in OD, 2.563 in overall width; the 1600 g mass converts to 1.600 kg (56.4 oz) for the bill of materials. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 55.5625 mm shaft inside the 65.1 mm total width while the outer ring is only 26 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "agricultural harvesting machinery", "heavy fan and heater units", "crusher and screen auxiliary shafts" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Do not specify the 55.5625 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 39.7 mm s1 dimension is the screw seating geometry inside the 39.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAR 212-203-2F as the grub two f execution; other order numbers of the YAR 212-203 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-212-203-2F?", "a": "Boundary dimensions: bore 55.5625 mm, sphered OD 110 mm, overall width 65.1 mm; weight 1600 g. Loads: dynamic 52.7 kN, static 36 kN, fatigue 1.53 kN; the only published speed is the 3,400 r/min limiting value." }, { "q": "What does the designation YAR 212-203-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -203 decodes as 2\" +3/16, i.e. 55.563 mm; the metric coded size YAR 212 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-212-203-2F", "YAR 212-203-2F" ], "locale_variants": {} }, { "sku": "YAT-212-204", "brand": "SKF", "manufacturer_designation": "YAT 212-204", "series": "YAR2-series", "type": "insert", "d_mm": 57.15, "D_mm": 110, "B_mm": 48.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 36, "fatigue_load_limit_kN": 1.53, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAT 212-204 is SKF's 57.15 mm-bore grub-screw insert bearing with the inner ring extended on one side in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 57.15x110x48.5 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAT prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring is extended on one side only. the three-digit -204 tail codes the bore in inches for inch-shaft bearings: 2 whole inch 4/16 in = 57.15 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 48.5 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals. Envelope 57.15x110x48.5 mm (2.25x4.331x1.909 in), outer ring 26 mm wide, C 52.7 kN, C0 36 kN, Pu 1.53 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,400 r/min; mass 1250 g. At the printed limiting speed of 3,400 r/min the mean diameter dm = 83.575 mm implies dn about 2.84x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Fatigue-limit check: Pu 1.53 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAT 212-204 — most belt-driven mounted-unit loads sit comfortably under 2.903 % of C. Grease-life arithmetic is dominated by speed: at dn approx 2.84x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Spherical-seat note in numbers: the 110 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 83.575 = 262.559 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Mass-to-load ratio for YAT-212-204: 23.719 g of catalogue mass per rated kN of C, and 21.872 g per millimetre of bore — useful when comparing executions of the same 57.15x110 mm envelope on the drawing. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Set-screw geometry on this size: the two 120 deg screws bear on the 57.15 mm shaft inside the 48.5 mm total width while the outer ring is only 26 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "agricultural harvesting machinery", "crusher and screen auxiliary shafts", "heavy fan and heater units" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Do not specify the 57.15 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 35 mm s1 dimension is the screw seating geometry inside the 22.5 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAT 212-204 as the grub one open execution; other order numbers of the YAT 212-204 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-212-204?", "a": "YAT 212-204 measures 57.15 mm bore x 110 mm OD x 48.5 mm overall width (outer ring 26 mm wide), 2.25 x 4.331 x 1.909 in; mass about 1250 g. SKF 17000 ratings: C 52.7 kN, C0 36 kN, Pu 1.53 kN, limiting speed 3,400 r/min." }, { "q": "What does the designation YAT 212-204 mean?", "a": "the YAT prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring is extended on one side only. the three-digit -204 tail codes the bore in inches for inch-shaft bearings: 2 whole inch 4/16 in = 57.15 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 48.5 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-212-204", "YAT 212-204" ], "locale_variants": {} }, { "sku": "YAR-212-204-2F", "brand": "SKF", "manufacturer_designation": "YAR 212-204-2F", "series": "YAR2-series", "type": "insert", "d_mm": 57.15, "D_mm": 110, "B_mm": 65.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 36, "fatigue_load_limit_kN": 1.53, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 212-204-2F is SKF's 57.15 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 57.15x110x65.1 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -204 tail codes the bore in inches for inch-shaft bearings: 2 whole inch 4/16 in = 57.15 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 57.15x110x65.1 mm (2.25x4.331x2.563 in), outer ring 26 mm wide, C 52.7 kN, C0 36 kN, Pu 1.53 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,400 r/min; mass 1550 g. Outer-vs-overall width: the outer ring is 26 mm wide inside the 65.1 mm total, so the extended inner ring accounts for 0.601 of the overall width (19.55 mm of axial projection per side). Envelope arithmetic: the radial section from 57.15 mm bore to 110 mm OD is 26.425 mm; dividing C 52.7 kN by that section gives 1.994 kN per section millimetre, and the 65.1 mm overall width is 2.464x the section. Fillet discipline: the printed r_min 1.5 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 57.15x110 mm insert on its chamfer tilts the whole spherical seat. Static-first planning: the 0.553 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 57.15 mm shaft, not the 52.7 kN L10 value. Pitch-diameter arithmetic: dm = (57.15+110)/2 = 83.575 mm; at the 3,400 r/min limiting speed the ball set runs at dn approx 2.84x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-212-204-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 26.425 mm radial section.", "applications": [ "crusher and screen auxiliary shafts", "heavy fan and heater units", "bulk-handling conveyor drives" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Do not specify the 57.15 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 39.7 mm s1 dimension is the screw seating geometry inside the 39.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAR 212-204-2F as the grub two f execution; other order numbers of the YAR 212-204 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-212-204-2F?", "a": "YAR 212-204-2F measures 57.15 mm bore x 110 mm OD x 65.1 mm overall width (outer ring 26 mm wide), 2.25 x 4.331 x 2.563 in; mass about 1550 g. SKF 17000 ratings: C 52.7 kN, C0 36 kN, Pu 1.53 kN, limiting speed 3,400 r/min." }, { "q": "What does the designation YAR 212-204-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -204 tail codes the bore in inches for inch-shaft bearings: 2 whole inch 4/16 in = 57.15 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-212-204-2F", "YAR 212-204-2F" ], "locale_variants": {} }, { "sku": "YAT-212-207", "brand": "SKF", "manufacturer_designation": "YAT 212-207", "series": "YAR2-series", "type": "insert", "d_mm": 61.912499999999994, "D_mm": 110, "B_mm": 48.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 36, "fatigue_load_limit_kN": 1.53, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAT 212-207 is a SKF insert bearing (Y-bearing) for a 61.912499999999994 mm (2.438 in) shaft: grub-screw insert bearing with the inner ring extended on one side, built to the ISO 15 diameter-series envelope with a sphered OD of 110 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. inch bore code -207 decodes as 2\" +7/16, i.e. 61.912 mm; the metric coded size YAT 212 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings. Envelope 61.912499999999994x110x48.5 mm (2.438x4.331x1.909 in), outer ring 26 mm wide, C 52.7 kN, C0 36 kN, Pu 1.53 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,400 r/min; mass 1100 g. Pitch-diameter arithmetic: dm = (61.912499999999994+110)/2 = 85.956 mm; at the 3,400 r/min limiting speed the ball set runs at dn approx 2.92x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Load balance for documentation: C0 36 kN against C 52.7 kN gives a 0.683 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 75.6 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Bore-to-OD planning: OD 110 over bore 61.912499999999994 is a 1.777x step, while bore/overall-width gives 1.277; the spherical seat in the matching Y-housing must be specified to the 110 mm OD, not to a cylindrical housing bore. Mass-to-load ratio for YAT-212-207: 20.873 g of catalogue mass per rated kN of C, and 17.767 g per millimetre of bore — useful when comparing executions of the same 61.912499999999994x110 mm envelope on the drawing. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Set-screw geometry on this size: the two 120 deg screws bear on the 61.912499999999994 mm shaft inside the 48.5 mm total width while the outer ring is only 26 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "heavy fan and heater units", "bulk-handling conveyor drives", "crusher and screen auxiliary shafts" ], "failure_modes": [ "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 61.912499999999994 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 35 mm s1 dimension is the screw seating geometry inside the 22.5 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 61.912499999999994 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-212-207?", "a": "Boundary dimensions: bore 61.912499999999994 mm, sphered OD 110 mm, overall width 48.5 mm; weight 1100 g. Loads: dynamic 52.7 kN, static 36 kN, fatigue 1.53 kN; the only published speed is the 3,400 r/min limiting value." }, { "q": "What does the designation YAT 212-207 mean?", "a": "reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. inch bore code -207 decodes as 2\" +7/16, i.e. 61.912 mm; the metric coded size YAT 212 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-212-207", "YAT 212-207" ], "locale_variants": {} }, { "sku": "YAR-212-207-2F", "brand": "SKF", "manufacturer_designation": "YAR 212-207-2F", "series": "YAR2-series", "type": "insert", "d_mm": 61.912499999999994, "D_mm": 110, "B_mm": 65.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 36, "fatigue_load_limit_kN": 1.53, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 212-207-2F is a SKF insert bearing (Y-bearing) for a 61.912499999999994 mm (2.438 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 110 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -207 decodes as 2\" +7/16, i.e. 61.912 mm; the metric coded size YAR 212 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 61.912499999999994x110x65.1 mm (2.438x4.331x2.563 in), outer ring 26 mm wide, C 52.7 kN, C0 36 kN, Pu 1.53 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,400 r/min; mass 1300 g. Fatigue-limit check: Pu 1.53 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAR 212-207-2F — most belt-driven mounted-unit loads sit comfortably under 2.903 % of C. Width accounting on this execution: 65.1 mm overall and 26 mm outer-ring width leave the housing designer 39.1 mm of inner-ring projection to accommodate the locking arrangement. Outer-vs-overall width: the outer ring is 26 mm wide inside the 65.1 mm total, so the extended inner ring accounts for 0.601 of the overall width (19.55 mm of axial projection per side). Spherical-seat note in numbers: the 110 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 85.956 = 270.039 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Selection figures for YAR 212-207-2F: C0/C is 0.683, Pu 1.53 kN is 2.903 % of the 52.7 kN dynamic rating, and the 1300 g catalogue mass works out to roughly 20.997 g per millimetre of the 61.912499999999994 mm bore. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 61.912499999999994 mm shaft inside the 65.1 mm total width while the outer ring is only 26 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "agricultural harvesting machinery", "heavy fan and heater units", "crusher and screen auxiliary shafts" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The 39.7 mm s1 dimension is the screw seating geometry inside the 39.1 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 61.912499999999994 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 52.7/36 kN figures belong specifically to YAR 212-207-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-212-207-2F?", "a": "Boundary dimensions: bore 61.912499999999994 mm, sphered OD 110 mm, overall width 65.1 mm; weight 1300 g. Loads: dynamic 52.7 kN, static 36 kN, fatigue 1.53 kN; the only published speed is the 3,400 r/min limiting value." }, { "q": "What does the designation YAR 212-207-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -207 decodes as 2\" +7/16, i.e. 61.912 mm; the metric coded size YAR 212 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-212-207-2F", "YAR 212-207-2F" ], "locale_variants": {} }, { "sku": "YAR-214-207-2F", "brand": "SKF", "manufacturer_designation": "YAR 214-207-2F", "series": "YAR2-series", "type": "insert", "d_mm": 61.912499999999994, "D_mm": 125, "B_mm": 69.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 62.4, "static_load_kN": 45, "fatigue_load_limit_kN": 1.86, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 2400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 214-207-2F is a grub-screw insert bearing with the inner ring extended on both sides, 61.912499999999994x125x69.9 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -207 = 61.912 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 61.912499999999994x125x69.9 mm (2.438x4.921x2.752 in), outer ring 28 mm wide, C 62.4 kN, C0 45 kN, Pu 1.86 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,800 r/min; mass 2400 g. Selection figures for YAR 214-207-2F: C0/C is 0.721, Pu 1.86 kN is 2.981 % of the 62.4 kN dynamic rating, and the 2400 g catalogue mass works out to roughly 38.764 g per millimetre of the 61.912499999999994 mm bore. At the printed limiting speed of 2,800 r/min the mean diameter dm = 93.456 mm implies dn about 2.62x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Outer-vs-overall width: the outer ring is 28 mm wide inside the 69.9 mm total, so the extended inner ring accounts for 0.599 of the overall width (20.95 mm of axial projection per side). Load balance for documentation: C0 45 kN against C 62.4 kN gives a 0.721 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Rating split for the maintenance file: dynamic 62.4 kN (L10), static 45 kN (s0 shock check), fatigue 1.86 kN (adjusted life) — three separate uses for YAR 214-207-2F, none interchangeable with another. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 61.912499999999994 mm shaft inside the 69.9 mm total width while the outer ring is only 28 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "crusher and screen auxiliary shafts", "bulk-handling conveyor drives", "agricultural harvesting machinery" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 61.912499999999994 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 39.7 mm s1 dimension is the screw seating geometry inside the 41.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 61.912499999999994 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-214-207-2F?", "a": "The catalogue envelope is 61.912499999999994x125x69.9 mm with a spherical outside surface; mass 2400 g. Ratings C 62.4/45 kN, Pu 1.86 kN, limiting speed 2,800 r/min." }, { "q": "What does the designation YAR 214-207-2F mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -207 = 61.912 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "How is YAR-214-207-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." }, { "q": "How do the set screws lock the 61.912499999999994 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-214-207-2F", "YAR 214-207-2F" ], "locale_variants": {} }, { "sku": "YAR-213-208-2RF", "brand": "SKF", "manufacturer_designation": "YAR 213-208-2RF", "series": "YAR2-series", "type": "insert", "d_mm": 63.5, "D_mm": 120, "B_mm": 68.3, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 57.2, "static_load_kN": 40, "fatigue_load_limit_kN": 1.7, "limiting_speed_rpm": 1600, "max_rpm": 1600, "weight_g": 1900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 213-208-2RF is a SKF insert bearing (Y-bearing) for a 63.5 mm (2.5 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 120 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -208 decodes as 2\" +8/16, i.e. 63.5 mm; the metric coded size YAR 213 shares the same envelope but its bore is the metric value, not this one. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments. Envelope 63.5x120x68.3 mm (2.5x4.724x2.689 in), outer ring 27 mm wide, C 57.2 kN, C0 40 kN, Pu 1.7 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,600 r/min; mass 1900 g. Load balance for documentation: C0 40 kN against C 57.2 kN gives a 0.699 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 82.5 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the rubberized flinger. Envelope arithmetic: the radial section from 63.5 mm bore to 120 mm OD is 28.25 mm; dividing C 57.2 kN by that section gives 2.025 kN per section millimetre, and the 68.3 mm overall width is 2.418x the section. Bore-to-OD planning: OD 120 over bore 63.5 is a 1.89x step, while bore/overall-width gives 0.93; the spherical seat in the matching Y-housing must be specified to the 120 mm OD, not to a cylindrical housing bore. Capacity density: 57.2 kN from 1.900 kg of bearing steel is about 30.105 kN per kilogram, and per width millimetre the 68.3 mm unit carries 0.837 kN of dynamic capacity. Rubberized-flinger note: the -2RF coated throwers are vulcanized assemblies — never lever or hammer against the flinger when mounting, and press only on the inner ring when the bearing is fitted loose before the housing cap closes, or the flinger lip folds inward and grinds on the inner ring. Service tip for YAR-213-208-2RF: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 28.25 mm radial section.", "applications": [ "bulk-handling conveyor drives", "crusher and screen auxiliary shafts", "agricultural harvesting machinery" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The 42.9 mm s1 dimension is the screw seating geometry inside the 41.3 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 63.5 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 57.2/40 kN figures belong specifically to YAR 213-208-2RF; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-213-208-2RF?", "a": "Boundary dimensions: bore 63.5 mm, sphered OD 120 mm, overall width 68.3 mm; weight 1900 g. Loads: dynamic 57.2 kN, static 40 kN, fatigue 1.7 kN; the only published speed is the 1,600 r/min limiting value." }, { "q": "What does the designation YAR 213-208-2RF mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -208 decodes as 2\" +8/16, i.e. 63.5 mm; the metric coded size YAR 213 shares the same envelope but its bore is the metric value, not this one. -2RF means an NBR contact lip plus a rubber-coated flinger at both sides, the catalogue step above -2F for wet, abrasive or washed-down environments." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-213-208-2RF lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR-213-208-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 63.5x120x68.3 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 213-208-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-213-208-2RF", "YAR 213-208-2RF" ], "locale_variants": {} }, { "sku": "YAR-213-208-2F", "brand": "SKF", "manufacturer_designation": "YAR 213-208-2F", "series": "YAR2-series", "type": "insert", "d_mm": 63.5, "D_mm": 120, "B_mm": 68.3, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 57.2, "static_load_kN": 40, "fatigue_load_limit_kN": 1.7, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 213-208-2F is SKF's 63.5 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 63.5x120x68.3 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -208 tail codes the bore in inches for inch-shaft bearings: 2 whole inch 8/16 in = 63.5 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 63.5x120x68.3 mm (2.5x4.724x2.689 in), outer ring 27 mm wide, C 57.2 kN, C0 40 kN, Pu 1.7 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,000 r/min; mass 1850 g. Outer-vs-overall width: the outer ring is 27 mm wide inside the 68.3 mm total, so the extended inner ring accounts for 0.605 of the overall width (20.65 mm of axial projection per side). Fatigue-limit check: Pu 1.7 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAR 213-208-2F — most belt-driven mounted-unit loads sit comfortably under 2.972 % of C. Selection figures for YAR 213-208-2F: C0/C is 0.699, Pu 1.7 kN is 2.972 % of the 57.2 kN dynamic rating, and the 1850 g catalogue mass works out to roughly 29.134 g per millimetre of the 63.5 mm bore. The s1 42.9 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Grease-life arithmetic is dominated by speed: at dn approx 2.75x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 63.5 mm shaft inside the 68.3 mm total width while the outer ring is only 27 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "crusher and screen auxiliary shafts", "bulk-handling conveyor drives", "agricultural harvesting machinery" ], "failure_modes": [ "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 63.5 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 42.9 mm s1 dimension is the screw seating geometry inside the 41.3 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 63.5 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-213-208-2F?", "a": "YAR 213-208-2F measures 63.5 mm bore x 120 mm OD x 68.3 mm overall width (outer ring 27 mm wide), 2.5 x 4.724 x 2.689 in; mass about 1850 g. SKF 17000 ratings: C 57.2 kN, C0 40 kN, Pu 1.7 kN, limiting speed 3,000 r/min." }, { "q": "What does the designation YAR 213-208-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -208 tail codes the bore in inches for inch-shaft bearings: 2 whole inch 8/16 in = 63.5 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR-213-208-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 63.5x120x68.3 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 213-208-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-213-208-2F", "YAR 213-208-2F" ], "locale_variants": {} }, { "sku": "YAR-214-208-2F", "brand": "SKF", "manufacturer_designation": "YAR 214-208-2F", "series": "YAR2-series", "type": "insert", "d_mm": 63.5, "D_mm": 125, "B_mm": 69.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 62.4, "static_load_kN": 45, "fatigue_load_limit_kN": 1.86, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 2300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YAR 214-208-2F is SKF's 63.5 mm-bore grub-screw insert bearing with the inner ring extended on both sides in the YAR2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 63.5x125x69.9 mm. Wide-inner-ring deep-groove ball geometry carries the load: the extended inner ring gives the shaft grip and the seal lands, while the outer ring stays narrow and spherically ground on its outside surface. the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -208 tail codes the bore in inches for inch-shaft bearings: 2 whole inch 8/16 in = 63.5 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 63.5x125x69.9 mm (2.5x4.921x2.752 in), outer ring 28 mm wide, C 62.4 kN, C0 45 kN, Pu 1.86 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,800 r/min; mass 2300 g. Bore-to-OD planning: OD 125 over bore 63.5 is a 1.969x step, while bore/overall-width gives 0.908; the spherical seat in the matching Y-housing must be specified to the 125 mm OD, not to a cylindrical housing bore. Spherical-seat note in numbers: the 125 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 94.25 = 296.095 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fatigue-limit check: Pu 1.86 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAR 214-208-2F — most belt-driven mounted-unit loads sit comfortably under 2.981 % of C. Envelope arithmetic: the radial section from 63.5 mm bore to 125 mm OD is 30.75 mm; dividing C 62.4 kN by that section gives 2.029 kN per section millimetre, and the 69.9 mm overall width is 2.273x the section. Outer-vs-overall width: the outer ring is 28 mm wide inside the 69.9 mm total, so the extended inner ring accounts for 0.599 of the overall width (20.95 mm of axial projection per side). Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 63.5 mm shaft inside the 69.9 mm total width while the outer ring is only 28 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "heavy fan and heater units", "bulk-handling conveyor drives", "crusher and screen auxiliary shafts" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The 39.7 mm s1 dimension is the screw seating geometry inside the 41.9 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 63.5 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 62.4/45 kN figures belong specifically to YAR 214-208-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-214-208-2F?", "a": "YAR 214-208-2F measures 63.5 mm bore x 125 mm OD x 69.9 mm overall width (outer ring 28 mm wide), 2.5 x 4.921 x 2.752 in; mass about 2300 g. SKF 17000 ratings: C 62.4 kN, C0 45 kN, Pu 1.86 kN, limiting speed 2,800 r/min." }, { "q": "What does the designation YAR 214-208-2F mean?", "a": "the YAR prefix names SKF grub-screw Y-bearings: two set screws in the extended inner ring lock the shaft at a 120 deg angle, and the inner ring extends symmetrically on both sides. the three-digit -208 tail codes the bore in inches for inch-shaft bearings: 2 whole inch 8/16 in = 63.5 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." }, { "q": "How is YAR-214-208-2F lubricated?", "a": "It is grease-filled and sealed for life at the factory; the housing fitting allows re-greasing through the outer-ring arrangement where provided. Never mix grease types on the food-grade HV/VE495 executions." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-214-208-2F", "YAR 214-208-2F" ], "locale_variants": {} }, { "sku": "YAR-213-211-2F", "brand": "SKF", "manufacturer_designation": "YAR 213-211-2F", "series": "YAR2-series", "type": "insert", "d_mm": 68.2625, "D_mm": 120, "B_mm": 68.3, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 57.2, "static_load_kN": 40, "fatigue_load_limit_kN": 1.7, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAR 213-211-2F is a SKF insert bearing (Y-bearing) for a 68.2625 mm (2.688 in) shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 120 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -211 decodes as 2\" +11/16, i.e. 68.263 mm; the metric coded size YAR 213 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 68.2625x120x68.3 mm (2.688x4.724x2.689 in), outer ring 27 mm wide, C 57.2 kN, C0 40 kN, Pu 1.7 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,000 r/min; mass 1600 g. Imperial procurement cross-check: 2.688 in bore, 4.724 in OD, 2.689 in overall width; the 1600 g mass converts to 1.600 kg (56.4 oz) for the bill of materials. Width accounting on this execution: 68.3 mm overall and 27 mm outer-ring width leave the housing designer 41.3 mm of inner-ring projection to accommodate the locking arrangement. Static-first planning: the 0.586 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 68.2625 mm shaft, not the 57.2 kN L10 value. Mass-to-load ratio for YAR-213-211-2F: 27.972 g of catalogue mass per rated kN of C, and 23.439 g per millimetre of bore — useful when comparing executions of the same 68.2625x120 mm envelope on the drawing. Rating split for the maintenance file: dynamic 57.2 kN (L10), static 40 kN (s0 shock check), fatigue 1.7 kN (adjusted life) — three separate uses for YAR 213-211-2F, none interchangeable with another. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-213-211-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 25.869 mm radial section.", "applications": [ "bulk-handling conveyor drives", "agricultural harvesting machinery", "heavy fan and heater units" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The 42.9 mm s1 dimension is the screw seating geometry inside the 41.3 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 68.2625 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 57.2/40 kN figures belong specifically to YAR 213-211-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-213-211-2F?", "a": "Boundary dimensions: bore 68.2625 mm, sphered OD 120 mm, overall width 68.3 mm; weight 1600 g. Loads: dynamic 57.2 kN, static 40 kN, fatigue 1.7 kN; the only published speed is the 3,000 r/min limiting value." }, { "q": "What does the designation YAR 213-211-2F mean?", "a": "reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. inch bore code -211 decodes as 2\" +11/16, i.e. 68.263 mm; the metric coded size YAR 213 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." }, { "q": "Why is the outside surface spherical?", "a": "The convex spherical OD mates with a matching spherical bore in the SKF Y-housing, accommodating initial STATIC misalignment at mounting. It is not a continuous-oscillation pivot and it does not work in a cylindrical plain bore." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-213-211-2F", "YAR 213-211-2F" ], "locale_variants": {} }, { "sku": "YAT-215-215", "brand": "SKF", "manufacturer_designation": "YAT 215-215", "series": "YAR2-series", "type": "insert", "d_mm": 74.6125, "D_mm": 130, "B_mm": 53.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 66.3, "static_load_kN": 49, "fatigue_load_limit_kN": 2.04, "limiting_speed_rpm": 2600, "max_rpm": 2600, "weight_g": 1750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YAR2 series order number YAT 215-215 is a SKF insert bearing (Y-bearing) for a 74.6125 mm (2.938 in) shaft: grub-screw insert bearing with the inner ring extended on one side, built to the ISO 15 diameter-series envelope with a sphered OD of 130 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. inch bore code -215 decodes as 2\" +15/16, i.e. 74.612 mm; the metric coded size YAT 215 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings. Envelope 74.6125x130x53.5 mm (2.938x5.118x2.106 in), outer ring 29 mm wide, C 66.3 kN, C0 49 kN, Pu 2.04 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,600 r/min; mass 1750 g. Bore-to-OD planning: OD 130 over bore 74.6125 is a 1.742x step, while bore/overall-width gives 1.395; the spherical seat in the matching Y-housing must be specified to the 130 mm OD, not to a cylindrical housing bore. Selection figures for YAT 215-215: C0/C is 0.739, Pu 2.04 kN is 3.077 % of the 66.3 kN dynamic rating, and the 1750 g catalogue mass works out to roughly 23.455 g per millimetre of the 74.6125 mm bore. Envelope arithmetic: the radial section from 74.6125 mm bore to 130 mm OD is 27.694 mm; dividing C 66.3 kN by that section gives 2.394 kN per section millimetre, and the 53.5 mm overall width is 1.932x the section. Spherical-seat note in numbers: the 130 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 102.306 = 321.404 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fatigue-limit check: Pu 2.04 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAT 215-215 — most belt-driven mounted-unit loads sit comfortably under 3.077 % of C. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Set-screw geometry on this size: the two 120 deg screws bear on the 74.6125 mm shaft inside the 53.5 mm total width while the outer ring is only 29 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "heavy fan and heater units", "crusher and screen auxiliary shafts", "bulk-handling conveyor drives" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The 39 mm s1 dimension is the screw seating geometry inside the 24.5 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Do not specify the 74.6125 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 66.3/49 kN figures belong specifically to YAT 215-215; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-215-215?", "a": "Boundary dimensions: bore 74.6125 mm, sphered OD 130 mm, overall width 53.5 mm; weight 1750 g. Loads: dynamic 66.3 kN, static 49 kN, fatigue 2.04 kN; the only published speed is the 2,600 r/min limiting value." }, { "q": "What does the designation YAT 215-215 mean?", "a": "reading the YAT basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAT carries the one-side-extended inner ring. inch bore code -215 decodes as 2\" +15/16, i.e. 74.612 mm; the metric coded size YAT 215 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YAR2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings." }, { "q": "How do the set screws lock the 74.6125 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-215-215", "YAT 215-215" ], "locale_variants": {} }, { "sku": "YAR-215-215-2F", "brand": "SKF", "manufacturer_designation": "YAR 215-215-2F", "series": "YAR2-series", "type": "insert", "d_mm": 74.6125, "D_mm": 130, "B_mm": 73.3, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 66.3, "static_load_kN": 49, "fatigue_load_limit_kN": 2.04, "limiting_speed_rpm": 2600, "max_rpm": 2600, "weight_g": 2150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 215-215-2F is a grub-screw insert bearing with the inner ring extended on both sides, 74.6125x130x73.3 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -215 = 74.612 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 74.6125x130x73.3 mm (2.938x5.118x2.886 in), outer ring 29 mm wide, C 66.3 kN, C0 49 kN, Pu 2.04 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,600 r/min; mass 2150 g. Selection figures for YAR 215-215-2F: C0/C is 0.739, Pu 2.04 kN is 3.077 % of the 66.3 kN dynamic rating, and the 2150 g catalogue mass works out to roughly 28.816 g per millimetre of the 74.6125 mm bore. Grease-life arithmetic is dominated by speed: at dn approx 2.66x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Capacity density: 66.3 kN from 2.150 kg of bearing steel is about 30.837 kN per kilogram, and per width millimetre the 73.3 mm unit carries 0.905 kN of dynamic capacity. The s1 46.3 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 92 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Set-screw geometry on this size: the two 120 deg screws bear on the 74.6125 mm shaft inside the 73.3 mm total width while the outer ring is only 29 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "crusher and screen auxiliary shafts", "bulk-handling conveyor drives", "agricultural harvesting machinery" ], "failure_modes": [ "set screws loosen under vibration or reversing load, letting the inner ring spin and fret the shaft at the screw points", "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Do not specify the 74.6125 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 46.3 mm s1 dimension is the screw seating geometry inside the 44.3 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Ordering discipline for the 74.6125 mm size: the chapter lists several executions side by side (YAR2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-215-215-2F?", "a": "The catalogue envelope is 74.6125x130x73.3 mm with a spherical outside surface; mass 2150 g. Ratings C 66.3/49 kN, Pu 2.04 kN, limiting speed 2,600 r/min." }, { "q": "What does the designation YAR 215-215-2F mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -215 = 74.612 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR-215-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 74.6125x130x73.3 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 215-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 74.6125 mm vs 75 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-215-215-2F", "YAR 215-215-2F" ], "locale_variants": {} }, { "sku": "YAT-216-300", "brand": "SKF", "manufacturer_designation": "YAT 216-300", "series": "YAR2-series", "type": "insert", "d_mm": 76.19999999999999, "D_mm": 140, "B_mm": 55.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 72.8, "static_load_kN": 53, "fatigue_load_limit_kN": 2.16, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 2200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAT 216-300 is a grub-screw insert bearing with the inner ring extended on one side, 76.19999999999999x140x55.5 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -300 = 76.2 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 76.19999999999999x140x55.5 mm (3x5.512x2.185 in), outer ring 30 mm wide, C 72.8 kN, C0 53 kN, Pu 2.16 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,400 r/min; mass 2200 g. Static-first planning: the 0.955 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 76.19999999999999 mm shaft, not the 72.8 kN L10 value. Bore-to-OD planning: OD 140 over bore 76.19999999999999 is a 1.837x step, while bore/overall-width gives 1.373; the spherical seat in the matching Y-housing must be specified to the 140 mm OD, not to a cylindrical housing bore. Fatigue-limit check: Pu 2.16 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YAT 216-300 — most belt-driven mounted-unit loads sit comfortably under 2.967 % of C. Pitch-diameter arithmetic: dm = (76.19999999999999+140)/2 = 108.1 mm; at the 2,400 r/min limiting speed the ball set runs at dn approx 2.59x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Load balance for documentation: C0 53 kN against C 72.8 kN gives a 0.728 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Single-extension fitting note: with the inner ring extended only on the locking side, orient the open (non-extended) face toward the shaft step or housing shoulder as the drawing shows — reversed, the set screws end up unsupported by the abutment and the shortened side offers no seal land at all. Set-screw geometry on this size: the two 120 deg screws bear on the 76.19999999999999 mm shaft inside the 55.5 mm total width while the outer ring is only 30 mm wide, leaving the extended ring to carry the screw points clear of the ball track.", "applications": [ "bulk-handling conveyor drives", "heavy fan and heater units", "agricultural harvesting machinery" ], "failure_modes": [ "over-tightened screw points dimple the shaft so deeply that the bearing cannot be removed without machining", "loose screws back out into the seal/flinger gap, tearing the NBR lip and admitting abrasive dust", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 76.19999999999999 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "The 39 mm s1 dimension is the screw seating geometry inside the 25.5 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Replacement discipline: a one-side YAT insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "Catalogue ratings belong to YAT 216-300 as the grub one open execution; other order numbers of the YAT 216-300 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAT-216-300?", "a": "The catalogue envelope is 76.19999999999999x140x55.5 mm with a spherical outside surface; mass 2200 g. Ratings C 72.8/53 kN, Pu 2.16 kN, limiting speed 2,400 r/min." }, { "q": "What does the designation YAT 216-300 mean?", "a": "YAT is SKF's grub-screw insert design — a single extended inner-ring side housing the two 120 deg set screws. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -300 = 76.2 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "How do the set screws lock the 76.19999999999999 mm shaft?", "a": "Two set screws in the extended inner ring, spaced 120 deg apart, are tightened in sequence against the shaft; their points create small indentations that resist rotation and axial drift. Use the SKF mounting procedure and re-check after run-in, especially on vibrating conveyors." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." } ], "cross_ref": [ { "equiv_sku": "YAT", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAT-216-300", "YAT 216-300" ], "locale_variants": {} }, { "sku": "YAR-216-300-2F", "brand": "SKF", "manufacturer_designation": "YAR 216-300-2F", "series": "YAR2-series", "type": "insert", "d_mm": 76.19999999999999, "D_mm": 140, "B_mm": 77.8, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 72.8, "static_load_kN": 53, "fatigue_load_limit_kN": 2.16, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 2800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YAR 216-300-2F is a grub-screw insert bearing with the inner ring extended on both sides, 76.19999999999999x140x77.8 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction follows the Y-bearing principle: a capped and flinger-protected deep-groove ball insert, inner ring elongated for the screw points, outer ring convex-spherical for the housing seat. YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -300 = 76.2 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 76.19999999999999x140x77.8 mm (3x5.512x3.063 in), outer ring 30 mm wide, C 72.8 kN, C0 53 kN, Pu 2.16 kN. The catalogue publishes a single speed ceiling, the limiting speed: 2,400 r/min; mass 2800 g. Fillet discipline: the printed r_min 2 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 76.19999999999999x140 mm insert on its chamfer tilts the whole spherical seat. Grease-life arithmetic is dominated by speed: at dn approx 2.59x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Static-first planning: the 0.681 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 76.19999999999999 mm shaft, not the 72.8 kN L10 value. Envelope arithmetic: the radial section from 76.19999999999999 mm bore to 140 mm OD is 31.9 mm; dividing C 72.8 kN by that section gives 2.282 kN per section millimetre, and the 77.8 mm overall width is 2.439x the section. Speed ceiling of 2,400 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-216-300-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 31.9 mm radial section.", "applications": [ "heavy fan and heater units", "crusher and screen auxiliary shafts", "bulk-handling conveyor drives" ], "failure_modes": [ "hammering the bearing onto a tight shaft through the outer ring brinells the ball tracks before first start-up", "shaft tolerance too loose for point locking: the screws deform the soft inner ring but never reach a rigid seat", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Do not specify the 76.19999999999999 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.", "Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.", "The 47.6 mm s1 dimension is the screw seating geometry inside the 47.8 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.", "Catalogue ratings belong to YAR 216-300-2F as the grub two f execution; other order numbers of the YAR 216-300 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YAR-216-300-2F?", "a": "The catalogue envelope is 76.19999999999999x140x77.8 mm with a spherical outside surface; mass 2800 g. Ratings C 72.8/53 kN, Pu 2.16 kN, limiting speed 2,400 r/min." }, { "q": "What does the designation YAR 216-300-2F mean?", "a": "YAR is SKF's grub-screw insert design — an inner ring extended equally past the outer ring on both sides, the screws still 120 deg apart. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -300 = 76.2 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "What is the difference between YAT and YAR?", "a": "YAT has the inner ring extended on ONE side (and in this chapter is the open execution); YAR extends the inner ring symmetrically on BOTH sides and is delivered with seal/flinger packages such as -2F or -2RF. Bore, OD and ball set are shared; overall width and sealing differ." }, { "q": "Can a grub-screw insert replace an eccentric-collar one?", "a": "Not without checking shaft and housing preparation: collar units need axial space for the collar and rely on rotation-direction self-tightening, while grub screws need clean shaft spots under the points. Same envelope does not mean same mounting." } ], "cross_ref": [ { "equiv_sku": "YAR", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YAR-216-300-2F", "YAR 216-300-2F" ], "locale_variants": {} }, { "sku": "YET-203-15", "brand": "SKF", "manufacturer_designation": "YET 203/15", "series": "YEL2-series", "type": "insert", "d_mm": 15, "D_mm": 40, "B_mm": 19.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 9.56, "static_load_kN": 4.75, "fatigue_load_limit_kN": 0.2, "limiting_speed_rpm": 9500, "max_rpm": 9500, "weight_g": 120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YET 203/15 is a SKF insert bearing (Y-bearing) for a 15 mm shaft: eccentric-locking-collar insert bearing with a one-side-extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 40 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YET means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on one side. the slash tail names a non-standard metric bore directly: YET 203/15 is the 15 mm bore execution of the size series. with no -2F/-2RF suffix the order number denotes the open external execution of the YEL2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings. Envelope 15x40x19.1 mm (0.591x1.575x0.752 in), outer ring 12 mm wide, C 9.56 kN, C0 4.75 kN, Pu 0.2 kN. Mounted width B1 28.6 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 9,500 r/min; mass 120 g. Mass-to-load ratio for YET-203-15: 12.552 g of catalogue mass per rated kN of C, and 8 g per millimetre of bore — useful when comparing executions of the same 15x40 mm envelope on the drawing. Envelope arithmetic: the radial section from 15 mm bore to 40 mm OD is 12.5 mm; dividing C 9.56 kN by that section gives 0.765 kN per section millimetre, and the 19.1 mm overall width is 1.528x the section. Speed ceiling of 9,500 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Spherical-seat note in numbers: the 40 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 27.5 = 86.394 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fatigue-limit check: Pu 0.2 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YET 203/15 — most belt-driven mounted-unit loads sit comfortably under 2.092 % of C. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Collar geometry for this size: over the 12 mm outer-ring width the inner ring runs to 19.1 mm overall (28.6 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "small garden machinery and rotavators", "light drive rollers with plain commercial shafts", "lawn and turf equipment" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Overall width 28.6 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 15 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "The 9.56/4.75 kN figures belong specifically to YET 203/15; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-203-15?", "a": "Boundary dimensions: bore 15 mm, sphered OD 40 mm, overall width 19.1 mm (28.6 mm with the collar); weight 120 g. Loads: dynamic 9.56 kN, static 4.75 kN, fatigue 0.2 kN; the only published speed is the 9,500 r/min limiting value." }, { "q": "What does the designation YET 203/15 mean?", "a": "YET means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on one side. the slash tail names a non-standard metric bore directly: YET 203/15 is the 15 mm bore execution of the size series. with no -2F/-2RF suffix the order number denotes the open external execution of the YEL2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-203-15", "YET 203/15" ], "locale_variants": {} }, { "sku": "YET-203", "brand": "SKF", "manufacturer_designation": "YET 203", "series": "YEL2-series", "type": "insert", "d_mm": 17, "D_mm": 40, "B_mm": 19.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 9.56, "static_load_kN": 4.75, "fatigue_load_limit_kN": 0.2, "limiting_speed_rpm": 9500, "max_rpm": 9500, "weight_g": 110, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YET 203 is SKF's 17 mm-bore eccentric-locking-collar insert bearing with a one-side-extended inner ring in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 17x40x19.1 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the size code 203 carries the usual bore arithmetic — 17 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. this suffix-free execution is listed without the sealed external design: the 19.1 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals. Envelope 17x40x19.1 mm (0.669x1.575x0.752 in), outer ring 12 mm wide, C 9.56 kN, C0 4.75 kN, Pu 0.2 kN. Mounted width B1 28.6 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 9,500 r/min; mass 110 g. Grease-life arithmetic is dominated by speed: at dn approx 2.71x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. At the printed limiting speed of 9,500 r/min the mean diameter dm = 28.5 mm implies dn about 2.71x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Load balance for documentation: C0 4.75 kN against C 9.56 kN gives a 0.497 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Bore-to-OD planning: OD 40 over bore 17 is a 2.353x step, while bore/overall-width gives 0.89; the spherical seat in the matching Y-housing must be specified to the 40 mm OD, not to a cylindrical housing bore. Speed ceiling of 9,500 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Collar geometry for this size: over the 12 mm outer-ring width the inner ring runs to 19.1 mm overall (28.6 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "lawn and turf equipment", "small garden machinery and rotavators", "light drive rollers with plain commercial shafts" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 28.6 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "The eccentric collar is handed to running direction; fit it wrong on the 17 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Ordering discipline for the 17 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-203?", "a": "YET 203 measures 17 mm bore x 40 mm OD x 19.1 mm overall width (outer ring 12 mm wide), 0.669 x 1.575 x 0.752 in; mass about 110 g. SKF 17000 ratings: C 9.56 kN, C0 4.75 kN, Pu 0.2 kN, limiting speed 9,500 r/min." }, { "q": "What does the designation YET 203 mean?", "a": "the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the size code 203 carries the usual bore arithmetic — 17 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. this suffix-free execution is listed without the sealed external design: the 19.1 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-203", "YET 203" ], "locale_variants": {} }, { "sku": "YET-204", "brand": "SKF", "manufacturer_designation": "YET 204", "series": "YEL2-series", "type": "insert", "d_mm": 20, "D_mm": 47, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 160, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YET 204 is a SKF insert bearing (Y-bearing) for a 20 mm shaft: eccentric-locking-collar insert bearing with a one-side-extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 47 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YET means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on one side. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. with no -2F/-2RF suffix the order number denotes the open external execution of the YEL2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings. Envelope 20x47x21 mm (0.787x1.85x0.827 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. Mounted width B1 30.5 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 8,500 r/min; mass 160 g. Bore-to-OD planning: OD 47 over bore 20 is a 2.35x step, while bore/overall-width gives 0.952; the spherical seat in the matching Y-housing must be specified to the 47 mm OD, not to a cylindrical housing bore. Pitch-diameter arithmetic: dm = (20+47)/2 = 33.5 mm; at the 8,500 r/min limiting speed the ball set runs at dn approx 2.85x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Outer-vs-overall width: the outer ring is 14 mm wide inside the 21 mm total, so the extended inner ring accounts for 0.333 of the overall width (7 mm of axial projection on the locking side). Envelope arithmetic: the radial section from 20 mm bore to 47 mm OD is 13.5 mm; dividing C 12.7 kN by that section gives 0.941 kN per section millimetre, and the 21 mm overall width is 1.556x the section. Imperial procurement cross-check: 0.787 in bore, 1.85 in OD, 0.827 in overall width; the 160 g mass converts to 0.160 kg (5.6 oz) for the bill of materials. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Collar geometry for this size: over the 14 mm outer-ring width the inner ring runs to 21 mm overall (30.5 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "light drive rollers with plain commercial shafts", "small garden machinery and rotavators", "lawn and turf equipment" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 20 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 30.5 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Catalogue ratings belong to YET 204 as the ecc one open execution; other order numbers of the YET 204 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-204?", "a": "Boundary dimensions: bore 20 mm, sphered OD 47 mm, overall width 21 mm (30.5 mm with the collar); weight 160 g. Loads: dynamic 12.7 kN, static 6.55 kN, fatigue 0.28 kN; the only published speed is the 8,500 r/min limiting value." }, { "q": "What does the designation YET 204 mean?", "a": "YET means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on one side. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. with no -2F/-2RF suffix the order number denotes the open external execution of the YEL2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YET-204-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x21 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 204/VL065 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-204", "YET 204" ], "locale_variants": {} }, { "sku": "YET-204-VL065", "brand": "SKF", "manufacturer_designation": "YET 204/VL065", "series": "YEL2-series", "type": "insert", "d_mm": 20, "D_mm": 47, "B_mm": 21, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 160, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YET 204/VL065 is SKF's 20 mm-bore eccentric-locking-collar insert bearing with a one-side-extended inner ring in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 20x47x21 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. /VL065 means the inner-ring bore and side faces are zinc coated: corrosion protection on the shaft seating and abutment faces without changing the seal package or the carbon-steel outer ring. Envelope 20x47x21 mm (0.787x1.85x0.827 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. Mounted width B1 30.5 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 8,500 r/min; mass 160 g. Width accounting: B1 30.5 mm covers the bearing WITH its eccentric locking collar against 21 mm for the bearing itself and 14 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Capacity density: 12.7 kN from 0.160 kg of bearing steel is about 79.375 kN per kilogram, and per width millimetre the 21 mm unit carries 0.605 kN of dynamic capacity. At the printed limiting speed of 8,500 r/min the mean diameter dm = 33.5 mm implies dn about 2.85x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Load balance for documentation: C0 6.55 kN against C 12.7 kN gives a 0.516 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Selection figures for YET 204/VL065: C0/C is 0.516, Pu 0.28 kN is 2.205 % of the 12.7 kN dynamic rating, and the 160 g catalogue mass works out to roughly 8 g per millimetre of the 20 mm bore. Zinc-coated one-side collar note: the VL065 layer protects the inner-ring bore and abutment faces; the eccentric collar itself is uncoated, so grease the collar-back interface to keep the zinc-free face from corroding fast to the inner ring. Collar geometry for this size: over the 14 mm outer-ring width the inner ring runs to 21 mm overall (30.5 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "small garden machinery and rotavators", "lawn and turf equipment", "light drive rollers with plain commercial shafts" ], "failure_modes": [ "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 30.5 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "The eccentric collar is handed to running direction; fit it wrong on the 20 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Ordering discipline for the 20 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-204-VL065?", "a": "YET 204/VL065 measures 20 mm bore x 47 mm OD x 21 mm overall width (outer ring 14 mm wide), 0.787 x 1.85 x 0.827 in; mass about 160 g. SKF 17000 ratings: C 12.7 kN, C0 6.55 kN, Pu 0.28 kN, limiting speed 8,500 r/min." }, { "q": "What does the designation YET 204/VL065 mean?", "a": "the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. /VL065 means the inner-ring bore and side faces are zinc coated: corrosion protection on the shaft seating and abutment faces without changing the seal package or the carbon-steel outer ring." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YET-204", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x21 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 204 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-204-VL065", "YET 204/VL065" ], "locale_variants": {} }, { "sku": "YELAG-204", "brand": "SKF", "manufacturer_designation": "YELAG 204", "series": "YEL2-series", "type": "insert", "d_mm": 20, "D_mm": 47, "B_mm": 34.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YELAG 204 is a SKF insert bearing (Y-bearing) for a 20 mm shaft: eccentric-locking-collar insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 47 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution. Envelope 20x47x34.2 mm (0.787x1.85x1.346 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. Mounted width B1 43.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 1,800 r/min; mass 200 g. At the printed limiting speed of 1,800 r/min the mean diameter dm = 33.5 mm implies dn about 0.60x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Load balance for documentation: C0 6.55 kN against C 12.7 kN gives a 0.516 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Mass-to-load ratio for YELAG-204: 15.748 g of catalogue mass per rated kN of C, and 10 g per millimetre of bore — useful when comparing executions of the same 20x47 mm envelope on the drawing. Imperial procurement cross-check: 0.787 in bore, 1.85 in OD, 1.346 in overall width; the 200 g mass converts to 0.200 kg (7.1 oz) for the bill of materials. Rating split for the maintenance file: dynamic 12.7 kN (L10), static 6.55 kN (s0 shock check), fatigue 0.28 kN (adjusted life) — three separate uses for YELAG 204, none interchangeable with another. Direction rule for YELAG-204: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 20 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "small garden machinery and rotavators", "light drive rollers with plain commercial shafts", "lawn and turf equipment" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Overall width 43.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 20 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "The 12.7/6.55 kN figures belong specifically to YELAG 204; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-204?", "a": "Boundary dimensions: bore 20 mm, sphered OD 47 mm, overall width 34.2 mm (43.7 mm with the collar); weight 200 g. Loads: dynamic 12.7 kN, static 6.55 kN, fatigue 0.28 kN; the only published speed is the 1,800 r/min limiting value." }, { "q": "What does the designation YELAG 204 mean?", "a": "YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YEL-204-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x34.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 204-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-204-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x34.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 204-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-204", "YELAG 204" ], "locale_variants": {} }, { "sku": "YEL-204-2RF-VL065", "brand": "SKF", "manufacturer_designation": "YEL 204-2RF/VL065", "series": "YEL2-series", "type": "insert", "d_mm": 20, "D_mm": 47, "B_mm": 34.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YEL 204-2RF/VL065 is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 20x47x34.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. VL065 adds zinc coating exactly where the inner ring meets the shaft and abutments; the rest of the bearing follows the standard design of the YEL2 size. Envelope 20x47x34.2 mm (0.787x1.85x1.346 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. Mounted width B1 43.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 5,000 r/min; mass 200 g. Spherical-seat note in numbers: the 47 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 33.5 = 105.243 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Pitch-diameter arithmetic: dm = (20+47)/2 = 33.5 mm; at the 5,000 r/min limiting speed the ball set runs at dn approx 1.68x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. At the printed limiting speed of 5,000 r/min the mean diameter dm = 33.5 mm implies dn about 1.68x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Mass-to-load ratio for YEL-204-2RF-VL065: 15.748 g of catalogue mass per rated kN of C, and 10 g per millimetre of bore — useful when comparing executions of the same 20x47 mm envelope on the drawing. Load balance for documentation: C0 6.55 kN against C 12.7 kN gives a 0.516 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Sealed zinc-coated collar note: VL065 covers the inner-ring bore and side faces under the -2RF seal set; the galvanized bore is slightly larger after coating, so use shafts in the lower half of the SKF tolerance band to avoid a skrink-fit that prevents collar removal. Collar geometry for this size: over the 14 mm outer-ring width the inner ring runs to 34.2 mm overall (43.7 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "light drive rollers with plain commercial shafts", "lawn and turf equipment", "small garden machinery and rotavators" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 20 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 43.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Ordering discipline for the 20 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-204-2RF-VL065?", "a": "The catalogue envelope is 20x47x34.2 mm with a spherical outside surface; mass 200 g. Ratings C 12.7/6.55 kN, Pu 0.28 kN, limiting speed 5,000 r/min." }, { "q": "What does the designation YEL 204-2RF/VL065 mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. VL065 adds zinc coating exactly where the inner ring meets the shaft and abutments; the rest of the bearing follows the standard design of the YEL2 size." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YELAG-204", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x34.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 204 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-204-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x34.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 204-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-204-2RF-VL065", "YEL 204-2RF/VL065" ], "locale_variants": {} }, { "sku": "YEL-204-2F", "brand": "SKF", "manufacturer_designation": "YEL 204-2F", "series": "YEL2-series", "type": "insert", "d_mm": 20, "D_mm": 47, "B_mm": 34.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YEL 204-2F is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 20x47x34.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 20x47x34.2 mm (0.787x1.85x1.346 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. Mounted width B1 43.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 8,500 r/min; mass 200 g. Rating split for the maintenance file: dynamic 12.7 kN (L10), static 6.55 kN (s0 shock check), fatigue 0.28 kN (adjusted life) — three separate uses for YEL 204-2F, none interchangeable with another. Capacity density: 12.7 kN from 0.200 kg of bearing steel is about 63.5 kN per kilogram, and per width millimetre the 34.2 mm unit carries 0.371 kN of dynamic capacity. Outer-vs-overall width: the outer ring is 14 mm wide inside the 34.2 mm total, so the extended inner ring accounts for 0.591 of the overall width (10.1 mm of axial projection per side). Static-first planning: the 0.192 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 20 mm shaft, not the 12.7 kN L10 value. Speed ceiling of 8,500 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Collar geometry for this size: over the 14 mm outer-ring width the inner ring runs to 34.2 mm overall (43.7 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "lawn and turf equipment", "light drive rollers with plain commercial shafts", "small garden machinery and rotavators" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Overall width 43.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "The eccentric collar is handed to running direction; fit it wrong on the 20 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The 12.7/6.55 kN figures belong specifically to YEL 204-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-204-2F?", "a": "The catalogue envelope is 20x47x34.2 mm with a spherical outside surface; mass 200 g. Ratings C 12.7/6.55 kN, Pu 0.28 kN, limiting speed 8,500 r/min." }, { "q": "What does the designation YEL 204-2F mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. the size code 204 carries the usual bore arithmetic — 20 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YELAG-204", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x34.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 204 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-204-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 20x47x34.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 204-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-204-2F", "YEL 204-2F" ], "locale_variants": {} }, { "sku": "YET-205", "brand": "SKF", "manufacturer_designation": "YET 205", "series": "YEL2-series", "type": "insert", "d_mm": 25, "D_mm": 52, "B_mm": 21.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YET 205 is SKF's 25 mm-bore eccentric-locking-collar insert bearing with a one-side-extended inner ring in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 25x52x21.5 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. this suffix-free execution is listed without the sealed external design: the 21.5 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals. Envelope 25x52x21.5 mm (0.984x2.047x0.846 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. Mounted width B1 31 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 7,000 r/min; mass 200 g. Load balance for documentation: C0 7.8 kN against C 14 kN gives a 0.557 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Outer-vs-overall width: the outer ring is 15 mm wide inside the 21.5 mm total, so the extended inner ring accounts for 0.302 of the overall width (6.5 mm of axial projection on the locking side). Imperial procurement cross-check: 0.984 in bore, 2.047 in OD, 0.846 in overall width; the 200 g mass converts to 0.200 kg (7.1 oz) for the bill of materials. Pitch-diameter arithmetic: dm = (25+52)/2 = 38.5 mm; at the 7,000 r/min limiting speed the ball set runs at dn approx 2.69x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Fatigue-limit check: Pu 0.335 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YET 205 — most belt-driven mounted-unit loads sit comfortably under 2.393 % of C. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Direction rule for YET-205: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 25 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes", "tiller and cultivator rotors" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 25 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 31 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Catalogue ratings belong to YET 205 as the ecc one open execution; other order numbers of the YET 205 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-205?", "a": "YET 205 measures 25 mm bore x 52 mm OD x 21.5 mm overall width (outer ring 15 mm wide), 0.984 x 2.047 x 0.846 in; mass about 200 g. SKF 17000 ratings: C 14 kN, C0 7.8 kN, Pu 0.335 kN, limiting speed 7,000 r/min." }, { "q": "What does the designation YET 205 mean?", "a": "the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. this suffix-free execution is listed without the sealed external design: the 21.5 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YET-205-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x21.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 205/VL065 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YET-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x21.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 205-100 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-205", "YET 205" ], "locale_variants": {} }, { "sku": "YET-205-VL065", "brand": "SKF", "manufacturer_designation": "YET 205/VL065", "series": "YEL2-series", "type": "insert", "d_mm": 25, "D_mm": 52, "B_mm": 21.5, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YET 205/VL065 is a eccentric-locking-collar insert bearing with a one-side-extended inner ring, 25x52x21.5 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. VL065 adds zinc coating exactly where the inner ring meets the shaft and abutments; the rest of the bearing follows the standard design of the YEL2 size. Envelope 25x52x21.5 mm (0.984x2.047x0.846 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. Mounted width B1 31 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 7,000 r/min; mass 200 g. Grease-life arithmetic is dominated by speed: at dn approx 2.69x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Imperial procurement cross-check: 0.984 in bore, 2.047 in OD, 0.846 in overall width; the 200 g mass converts to 0.200 kg (7.1 oz) for the bill of materials. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 25x52 mm insert on its chamfer tilts the whole spherical seat. The s1 23.5 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. At the printed limiting speed of 7,000 r/min the mean diameter dm = 38.5 mm implies dn about 2.69x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Zinc-coated one-side collar note: the VL065 layer protects the inner-ring bore and abutment faces; the eccentric collar itself is uncoated, so grease the collar-back interface to keep the zinc-free face from corroding fast to the inner ring. Direction rule for YET-205-VL065: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 25 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "ventilation equipment with frequent bearing changes", "agricultural machinery PTO-driven shafts", "tiller and cultivator rotors" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 25 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 31 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Catalogue ratings belong to YET 205/VL065 as the ecc one vl065 execution; other order numbers of the YET 205 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-205-VL065?", "a": "The catalogue envelope is 25x52x21.5 mm with a spherical outside surface; mass 200 g. Ratings C 14/7.8 kN, Pu 0.335 kN, limiting speed 7,000 r/min." }, { "q": "What does the designation YET 205/VL065 mean?", "a": "reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. VL065 adds zinc coating exactly where the inner ring meets the shaft and abutments; the rest of the bearing follows the standard design of the YEL2 size." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YET-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x21.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 205 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YET-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x21.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 205-100 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-205-VL065", "YET 205/VL065" ], "locale_variants": {} }, { "sku": "YELAG-205", "brand": "SKF", "manufacturer_designation": "YELAG 205", "series": "YEL2-series", "type": "insert", "d_mm": 25, "D_mm": 52, "B_mm": 34.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 1500, "max_rpm": 1500, "weight_g": 240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YELAG 205 is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 25x52x34.9 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 25x52x34.9 mm (0.984x2.047x1.374 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. Mounted width B1 44.4 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 1,500 r/min; mass 240 g. Grease-life arithmetic is dominated by speed: at dn approx 0.58x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the AG variant caps speed so aggressively, and high-temperature mounts shorten both even when load is light. At the printed limiting speed of 1,500 r/min the mean diameter dm = 38.5 mm implies dn about 0.58x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 33.7 mm, d2 37.4 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Static-first planning: the 0.223 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 25 mm shaft, not the 14 kN L10 value. Fatigue-limit check: Pu 0.335 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YELAG 205 — most belt-driven mounted-unit loads sit comfortably under 2.393 % of C. Collar geometry for this size: over the 15 mm outer-ring width the inner ring runs to 34.9 mm overall (44.4 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "ventilation equipment with frequent bearing changes", "one-direction conveyor drives", "tiller and cultivator rotors" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 25 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 44.4 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Catalogue ratings belong to YELAG 205 as the ecc two ag execution; other order numbers of the YELAG 205 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-205?", "a": "The catalogue envelope is 25x52x34.9 mm with a spherical outside surface; mass 240 g. Ratings C 14/7.8 kN, Pu 0.335 kN, limiting speed 1,500 r/min." }, { "q": "What does the designation YELAG 205 mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YEL-205-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 205-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-205-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 205-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YELAG-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 205-100 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-205-100-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 205-100-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-205", "YELAG 205" ], "locale_variants": {} }, { "sku": "YEL-205-2RF-VL065", "brand": "SKF", "manufacturer_designation": "YEL 205-2RF/VL065", "series": "YEL2-series", "type": "insert", "d_mm": 25, "D_mm": 52, "B_mm": 34.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YEL 205-2RF/VL065 is SKF's 25 mm-bore eccentric-locking-collar insert bearing with the inner ring extended on both sides in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 25x52x34.9 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. /VL065 means the inner-ring bore and side faces are zinc coated: corrosion protection on the shaft seating and abutment faces without changing the seal package or the carbon-steel outer ring. Envelope 25x52x34.9 mm (0.984x2.047x1.374 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. Mounted width B1 44.4 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 250 g. The s1 26.9 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. At the printed limiting speed of 4,300 r/min the mean diameter dm = 38.5 mm implies dn about 1.66x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Bore-to-OD planning: OD 52 over bore 25 is a 2.08x step, while bore/overall-width gives 0.716; the spherical seat in the matching Y-housing must be specified to the 52 mm OD, not to a cylindrical housing bore. Pitch-diameter arithmetic: dm = (25+52)/2 = 38.5 mm; at the 4,300 r/min limiting speed the ball set runs at dn approx 1.66x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Width accounting: B1 44.4 mm covers the bearing WITH its eccentric locking collar against 34.9 mm for the bearing itself and 15 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Sealed zinc-coated collar note: VL065 covers the inner-ring bore and side faces under the -2RF seal set; the galvanized bore is slightly larger after coating, so use shafts in the lower half of the SKF tolerance band to avoid a skrink-fit that prevents collar removal. Direction rule for YEL-205-2RF-VL065: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 25 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "agricultural machinery PTO-driven shafts", "one-direction conveyor drives", "ventilation equipment with frequent bearing changes" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Overall width 44.4 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 25 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "The 14/7.8 kN figures belong specifically to YEL 205-2RF/VL065; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-205-2RF-VL065?", "a": "YEL 205-2RF/VL065 measures 25 mm bore x 52 mm OD x 34.9 mm overall width (outer ring 15 mm wide), 0.984 x 2.047 x 1.374 in; mass about 250 g. SKF 17000 ratings: C 14 kN, C0 7.8 kN, Pu 0.335 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YEL 205-2RF/VL065 mean?", "a": "the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. /VL065 means the inner-ring bore and side faces are zinc coated: corrosion protection on the shaft seating and abutment faces without changing the seal package or the carbon-steel outer ring." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YELAG-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 205 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-205-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 205-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YELAG-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 205-100 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-205-100-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 205-100-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-205-2RF-VL065", "YEL 205-2RF/VL065" ], "locale_variants": {} }, { "sku": "YEL-205-2F", "brand": "SKF", "manufacturer_designation": "YEL 205-2F", "series": "YEL2-series", "type": "insert", "d_mm": 25, "D_mm": 52, "B_mm": 34.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YEL 205-2F is a SKF insert bearing (Y-bearing) for a 25 mm shaft: eccentric-locking-collar insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 52 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 25x52x34.9 mm (0.984x2.047x1.374 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. Mounted width B1 44.4 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 7,000 r/min; mass 240 g. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 25x52 mm insert on its chamfer tilts the whole spherical seat. Bore-to-OD planning: OD 52 over bore 25 is a 2.08x step, while bore/overall-width gives 0.716; the spherical seat in the matching Y-housing must be specified to the 52 mm OD, not to a cylindrical housing bore. Width accounting: B1 44.4 mm covers the bearing WITH its eccentric locking collar against 34.9 mm for the bearing itself and 15 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Pitch-diameter arithmetic: dm = (25+52)/2 = 38.5 mm; at the 7,000 r/min limiting speed the ball set runs at dn approx 2.69x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Spherical-seat note in numbers: the 52 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 38.5 = 120.951 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Collar geometry for this size: over the 15 mm outer-ring width the inner ring runs to 34.9 mm overall (44.4 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "tiller and cultivator rotors", "one-direction conveyor drives", "agricultural machinery PTO-driven shafts" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Overall width 44.4 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 25 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "The 14/7.8 kN figures belong specifically to YEL 205-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-205-2F?", "a": "Boundary dimensions: bore 25 mm, sphered OD 52 mm, overall width 34.9 mm (44.4 mm with the collar); weight 240 g. Loads: dynamic 14 kN, static 7.8 kN, fatigue 0.335 kN; the only published speed is the 7,000 r/min limiting value." }, { "q": "What does the designation YEL 205-2F mean?", "a": "YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YELAG-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 205 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-205-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 205-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YELAG-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 205-100 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-205-100-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 205-100-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-205-2F", "YEL 205-2F" ], "locale_variants": {} }, { "sku": "YET-206", "brand": "SKF", "manufacturer_designation": "YET 206", "series": "YEL2-series", "type": "insert", "d_mm": 30, "D_mm": 62, "B_mm": 23.8, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 320, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YET 206 is SKF's 30 mm-bore eccentric-locking-collar insert bearing with a one-side-extended inner ring in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 30x62x23.8 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. this suffix-free execution is listed without the sealed external design: the 23.8 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals. Envelope 30x62x23.8 mm (1.181x2.441x0.937 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. Mounted width B1 35.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 320 g. Envelope arithmetic: the radial section from 30 mm bore to 62 mm OD is 16 mm; dividing C 19.5 kN by that section gives 1.219 kN per section millimetre, and the 23.8 mm overall width is 1.488x the section. The s1 26.7 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Rating split for the maintenance file: dynamic 19.5 kN (L10), static 11.2 kN (s0 shock check), fatigue 0.475 kN (adjusted life) — three separate uses for YET 206, none interchangeable with another. Bore-to-OD planning: OD 62 over bore 30 is a 2.067x step, while bore/overall-width gives 1.261; the spherical seat in the matching Y-housing must be specified to the 62 mm OD, not to a cylindrical housing bore. Speed ceiling of 6,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Collar geometry for this size: over the 18 mm outer-ring width the inner ring runs to 23.8 mm overall (35.7 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "tiller and cultivator rotors", "agricultural machinery PTO-driven shafts", "one-direction conveyor drives" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 30 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 35.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Catalogue ratings belong to YET 206 as the ecc one open execution; other order numbers of the YET 206 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-206?", "a": "YET 206 measures 30 mm bore x 62 mm OD x 23.8 mm overall width (outer ring 18 mm wide), 1.181 x 2.441 x 0.937 in; mass about 320 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YET 206 mean?", "a": "the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. this suffix-free execution is listed without the sealed external design: the 23.8 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YET-206-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x23.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 206/VL065 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YET-206-103", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x23.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 206-103 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-206", "YET 206" ], "locale_variants": {} }, { "sku": "YET-206-VL065", "brand": "SKF", "manufacturer_designation": "YET 206/VL065", "series": "YEL2-series", "type": "insert", "d_mm": 30, "D_mm": 62, "B_mm": 23.8, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 320, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YET 206/VL065 is SKF's 30 mm-bore eccentric-locking-collar insert bearing with a one-side-extended inner ring in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 30x62x23.8 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. /VL065 means the inner-ring bore and side faces are zinc coated: corrosion protection on the shaft seating and abutment faces without changing the seal package or the carbon-steel outer ring. Envelope 30x62x23.8 mm (1.181x2.441x0.937 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. Mounted width B1 35.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 320 g. Outer-vs-overall width: the outer ring is 18 mm wide inside the 23.8 mm total, so the extended inner ring accounts for 0.244 of the overall width (5.8 mm of axial projection on the locking side). Grease-life arithmetic is dominated by speed: at dn approx 2.90x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Width accounting: B1 35.7 mm covers the bearing WITH its eccentric locking collar against 23.8 mm for the bearing itself and 18 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Static-first planning: the 0.471 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 30 mm shaft, not the 19.5 kN L10 value. Bore-to-OD planning: OD 62 over bore 30 is a 2.067x step, while bore/overall-width gives 1.261; the spherical seat in the matching Y-housing must be specified to the 62 mm OD, not to a cylindrical housing bore. Zinc-coated one-side collar note: the VL065 layer protects the inner-ring bore and abutment faces; the eccentric collar itself is uncoated, so grease the collar-back interface to keep the zinc-free face from corroding fast to the inner ring. Collar geometry for this size: over the 18 mm outer-ring width the inner ring runs to 23.8 mm overall (35.7 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "one-direction conveyor drives", "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes" ], "failure_modes": [ "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 35.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "The eccentric collar is handed to running direction; fit it wrong on the 30 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Ordering discipline for the 30 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-206-VL065?", "a": "YET 206/VL065 measures 30 mm bore x 62 mm OD x 23.8 mm overall width (outer ring 18 mm wide), 1.181 x 2.441 x 0.937 in; mass about 320 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YET 206/VL065 mean?", "a": "the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. /VL065 means the inner-ring bore and side faces are zinc coated: corrosion protection on the shaft seating and abutment faces without changing the seal package or the carbon-steel outer ring." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YET-206", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x23.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 206 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YET-206-103", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x23.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 206-103 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-206-VL065", "YET 206/VL065" ], "locale_variants": {} }, { "sku": "YELAG-206", "brand": "SKF", "manufacturer_designation": "YELAG 206", "series": "YEL2-series", "type": "insert", "d_mm": 30, "D_mm": 62, "B_mm": 36.5, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 1200, "max_rpm": 1200, "weight_g": 380, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YELAG 206 is SKF's 30 mm-bore eccentric-locking-collar insert bearing with the inner ring extended on both sides in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 30x62x36.5 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant. Envelope 30x62x36.5 mm (1.181x2.441x1.437 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. Mounted width B1 48.4 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 1,200 r/min; mass 380 g. Width accounting: B1 48.4 mm covers the bearing WITH its eccentric locking collar against 36.5 mm for the bearing itself and 18 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Pitch-diameter arithmetic: dm = (30+62)/2 = 46 mm; at the 1,200 r/min limiting speed the ball set runs at dn approx 0.55x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 30x62 mm insert on its chamfer tilts the whole spherical seat. Load balance for documentation: C0 11.2 kN against C 19.5 kN gives a 0.574 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Bore-to-OD planning: OD 62 over bore 30 is a 2.067x step, while bore/overall-width gives 0.822; the spherical seat in the matching Y-housing must be specified to the 62 mm OD, not to a cylindrical housing bore. Direction rule for YELAG-206: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 30 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "one-direction conveyor drives", "tiller and cultivator rotors", "agricultural machinery PTO-driven shafts" ], "failure_modes": [ "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 30 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 48.4 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Catalogue ratings belong to YELAG 206 as the ecc two ag execution; other order numbers of the YELAG 206 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-206?", "a": "YELAG 206 measures 30 mm bore x 62 mm OD x 36.5 mm overall width (outer ring 18 mm wide), 1.181 x 2.441 x 1.437 in; mass about 380 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 1,200 r/min." }, { "q": "What does the designation YELAG 206 mean?", "a": "the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YEL-206-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 206-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-206-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 206-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YELAG-206-103", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 206-103 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-206-103-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 206-103-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-206", "YELAG 206" ], "locale_variants": {} }, { "sku": "YEL-206-2RF-VL065", "brand": "SKF", "manufacturer_designation": "YEL 206-2RF/VL065", "series": "YEL2-series", "type": "insert", "d_mm": 30, "D_mm": 62, "B_mm": 36.5, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 380, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YEL 206-2RF/VL065 is SKF's 30 mm-bore eccentric-locking-collar insert bearing with the inner ring extended on both sides in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 30x62x36.5 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. /VL065 means the inner-ring bore and side faces are zinc coated: corrosion protection on the shaft seating and abutment faces without changing the seal package or the carbon-steel outer ring. Envelope 30x62x36.5 mm (1.181x2.441x1.437 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. Mounted width B1 48.4 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 3,800 r/min; mass 380 g. Imperial procurement cross-check: 1.181 in bore, 2.441 in OD, 1.437 in overall width; the 380 g mass converts to 0.380 kg (13.4 oz) for the bill of materials. Speed ceiling of 3,800 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Bore-to-OD planning: OD 62 over bore 30 is a 2.067x step, while bore/overall-width gives 0.822; the spherical seat in the matching Y-housing must be specified to the 62 mm OD, not to a cylindrical housing bore. Pitch-diameter arithmetic: dm = (30+62)/2 = 46 mm; at the 3,800 r/min limiting speed the ball set runs at dn approx 1.75x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Width accounting: B1 48.4 mm covers the bearing WITH its eccentric locking collar against 36.5 mm for the bearing itself and 18 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Sealed zinc-coated collar note: VL065 covers the inner-ring bore and side faces under the -2RF seal set; the galvanized bore is slightly larger after coating, so use shafts in the lower half of the SKF tolerance band to avoid a skrink-fit that prevents collar removal. Collar geometry for this size: over the 18 mm outer-ring width the inner ring runs to 36.5 mm overall (48.4 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes", "tiller and cultivator rotors" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 30 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 48.4 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Catalogue ratings belong to YEL 206-2RF/VL065 as the ecc two vl065 execution; other order numbers of the YEL 206 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-206-2RF-VL065?", "a": "YEL 206-2RF/VL065 measures 30 mm bore x 62 mm OD x 36.5 mm overall width (outer ring 18 mm wide), 1.181 x 2.441 x 1.437 in; mass about 380 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 3,800 r/min." }, { "q": "What does the designation YEL 206-2RF/VL065 mean?", "a": "the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. /VL065 means the inner-ring bore and side faces are zinc coated: corrosion protection on the shaft seating and abutment faces without changing the seal package or the carbon-steel outer ring." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YELAG-206", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 206 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-206-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 206-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YELAG-206-103", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 206-103 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-206-103-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 206-103-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-206-2RF-VL065", "YEL 206-2RF/VL065" ], "locale_variants": {} }, { "sku": "YEL-206-2F", "brand": "SKF", "manufacturer_designation": "YEL 206-2F", "series": "YEL2-series", "type": "insert", "d_mm": 30, "D_mm": 62, "B_mm": 36.5, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 380, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YEL 206-2F is SKF's 30 mm-bore eccentric-locking-collar insert bearing with the inner ring extended on both sides in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 30x62x36.5 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 30x62x36.5 mm (1.181x2.441x1.437 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. Mounted width B1 48.4 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 380 g. Grease-life arithmetic is dominated by speed: at dn approx 2.90x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Rating split for the maintenance file: dynamic 19.5 kN (L10), static 11.2 kN (s0 shock check), fatigue 0.475 kN (adjusted life) — three separate uses for YEL 206-2F, none interchangeable with another. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 39.7 mm, d2 44.1 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Load balance for documentation: C0 11.2 kN against C 19.5 kN gives a 0.574 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Envelope arithmetic: the radial section from 30 mm bore to 62 mm OD is 16 mm; dividing C 19.5 kN by that section gives 1.219 kN per section millimetre, and the 36.5 mm overall width is 2.281x the section. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Collar geometry for this size: over the 18 mm outer-ring width the inner ring runs to 36.5 mm overall (48.4 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "ventilation equipment with frequent bearing changes", "one-direction conveyor drives", "tiller and cultivator rotors" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 48.4 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "The eccentric collar is handed to running direction; fit it wrong on the 30 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Ordering discipline for the 30 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-206-2F?", "a": "YEL 206-2F measures 30 mm bore x 62 mm OD x 36.5 mm overall width (outer ring 18 mm wide), 1.181 x 2.441 x 1.437 in; mass about 380 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YEL 206-2F mean?", "a": "the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YELAG-206", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 206 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-206-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 206-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YELAG-206-103", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 206-103 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-206-103-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 206-103-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-206-2F", "YEL 206-2F" ], "locale_variants": {} }, { "sku": "YET-207", "brand": "SKF", "manufacturer_designation": "YET 207", "series": "YEL2-series", "type": "insert", "d_mm": 35, "D_mm": 72, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 460, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YET 207 is a SKF insert bearing (Y-bearing) for a 35 mm shaft: eccentric-locking-collar insert bearing with a one-side-extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YET means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on one side. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. with no -2F/-2RF suffix the order number denotes the open external execution of the YEL2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings. Envelope 35x72x25.4 mm (1.378x2.835x1 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 38.9 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 460 g. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 35x72 mm insert on its chamfer tilts the whole spherical seat. Fatigue-limit check: Pu 0.655 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YET 207 — most belt-driven mounted-unit loads sit comfortably under 2.569 % of C. Spherical-seat note in numbers: the 72 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 53.5 = 168.075 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Capacity density: 25.5 kN from 0.460 kg of bearing steel is about 55.435 kN per kilogram, and per width millimetre the 25.4 mm unit carries 1.004 kN of dynamic capacity. Static-first planning: the 0.602 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 35 mm shaft, not the 25.5 kN L10 value. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Direction rule for YET-207: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 35 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "tiller and cultivator rotors", "one-direction conveyor drives", "agricultural machinery PTO-driven shafts" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 38.9 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "The eccentric collar is handed to running direction; fit it wrong on the 35 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Ordering discipline for the 35 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-207?", "a": "Boundary dimensions: bore 35 mm, sphered OD 72 mm, overall width 25.4 mm (38.9 mm with the collar); weight 460 g. Loads: dynamic 25.5 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 5,300 r/min limiting value." }, { "q": "What does the designation YET 207 mean?", "a": "YET means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on one side. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. with no -2F/-2RF suffix the order number denotes the open external execution of the YEL2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YET-207-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x25.4 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 207/VL065 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YET-207-106", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x25.4 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 207-106 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-207", "YET 207" ], "locale_variants": {} }, { "sku": "YET-207-VL065", "brand": "SKF", "manufacturer_designation": "YET 207/VL065", "series": "YEL2-series", "type": "insert", "d_mm": 35, "D_mm": 72, "B_mm": 25.4, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 460, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YET 207/VL065 is SKF's 35 mm-bore eccentric-locking-collar insert bearing with a one-side-extended inner ring in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 35x72x25.4 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. /VL065 means the inner-ring bore and side faces are zinc coated: corrosion protection on the shaft seating and abutment faces without changing the seal package or the carbon-steel outer ring. Envelope 35x72x25.4 mm (1.378x2.835x1 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 38.9 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 460 g. Width accounting: B1 38.9 mm covers the bearing WITH its eccentric locking collar against 25.4 mm for the bearing itself and 19 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Envelope arithmetic: the radial section from 35 mm bore to 72 mm OD is 18.5 mm; dividing C 25.5 kN by that section gives 1.378 kN per section millimetre, and the 25.4 mm overall width is 1.373x the section. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 35x72 mm insert on its chamfer tilts the whole spherical seat. Static-first planning: the 0.602 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 35 mm shaft, not the 25.5 kN L10 value. Capacity density: 25.5 kN from 0.460 kg of bearing steel is about 55.435 kN per kilogram, and per width millimetre the 25.4 mm unit carries 1.004 kN of dynamic capacity. Zinc-coated one-side collar note: the VL065 layer protects the inner-ring bore and abutment faces; the eccentric collar itself is uncoated, so grease the collar-back interface to keep the zinc-free face from corroding fast to the inner ring. Direction rule for YET-207-VL065: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 35 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "one-direction conveyor drives", "tiller and cultivator rotors", "agricultural machinery PTO-driven shafts" ], "failure_modes": [ "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Overall width 38.9 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "The eccentric collar is handed to running direction; fit it wrong on the 35 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The 25.5/15.3 kN figures belong specifically to YET 207/VL065; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-207-VL065?", "a": "YET 207/VL065 measures 35 mm bore x 72 mm OD x 25.4 mm overall width (outer ring 19 mm wide), 1.378 x 2.835 x 1 in; mass about 460 g. SKF 17000 ratings: C 25.5 kN, C0 15.3 kN, Pu 0.655 kN, limiting speed 5,300 r/min." }, { "q": "What does the designation YET 207/VL065 mean?", "a": "the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. /VL065 means the inner-ring bore and side faces are zinc coated: corrosion protection on the shaft seating and abutment faces without changing the seal package or the carbon-steel outer ring." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YET-207", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x25.4 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 207 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YET-207-106", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x25.4 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 207-106 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-207-VL065", "YET 207/VL065" ], "locale_variants": {} }, { "sku": "YELAG-207", "brand": "SKF", "manufacturer_designation": "YELAG 207", "series": "YEL2-series", "type": "insert", "d_mm": 35, "D_mm": 72, "B_mm": 37.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 530, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YELAG 207 is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 35x72x37.6 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 35x72x37.6 mm (1.378x2.835x1.48 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 51.1 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 1,100 r/min; mass 530 g. Imperial procurement cross-check: 1.378 in bore, 2.835 in OD, 1.48 in overall width; the 530 g mass converts to 0.530 kg (18.7 oz) for the bill of materials. Outer-vs-overall width: the outer ring is 19 mm wide inside the 37.6 mm total, so the extended inner ring accounts for 0.495 of the overall width (9.3 mm of axial projection per side). Load balance for documentation: C0 15.3 kN against C 25.5 kN gives a 0.6 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 35x72 mm insert on its chamfer tilts the whole spherical seat. Grease-life arithmetic is dominated by speed: at dn approx 0.59x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the AG variant caps speed so aggressively, and high-temperature mounts shorten both even when load is light. Direction rule for YELAG-207: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 35 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes", "tiller and cultivator rotors" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Overall width 51.1 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 35 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "The 25.5/15.3 kN figures belong specifically to YELAG 207; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-207?", "a": "The catalogue envelope is 35x72x37.6 mm with a spherical outside surface; mass 530 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 1,100 r/min." }, { "q": "What does the designation YELAG 207 mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YEL-207-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 207-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-207-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 207-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YELAG-207-106", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 207-106 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-207-106-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 207-106-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-207", "YELAG 207" ], "locale_variants": {} }, { "sku": "YEL-207-2RF-VL065", "brand": "SKF", "manufacturer_designation": "YEL 207-2RF/VL065", "series": "YEL2-series", "type": "insert", "d_mm": 35, "D_mm": 72, "B_mm": 37.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 540, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YEL 207-2RF/VL065 is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 35x72x37.6 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. VL065 adds zinc coating exactly where the inner ring meets the shaft and abutments; the rest of the bearing follows the standard design of the YEL2 size. Envelope 35x72x37.6 mm (1.378x2.835x1.48 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 51.1 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 3,200 r/min; mass 540 g. Selection figures for YEL 207-2RF/VL065: C0/C is 0.6, Pu 0.655 kN is 2.569 % of the 25.5 kN dynamic rating, and the 540 g catalogue mass works out to roughly 15.429 g per millimetre of the 35 mm bore. Capacity density: 25.5 kN from 0.540 kg of bearing steel is about 47.222 kN per kilogram, and per width millimetre the 37.6 mm unit carries 0.678 kN of dynamic capacity. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 46.1 mm, d2 51.1 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Spherical-seat note in numbers: the 72 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 53.5 = 168.075 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Imperial procurement cross-check: 1.378 in bore, 2.835 in OD, 1.48 in overall width; the 540 g mass converts to 0.540 kg (19.0 oz) for the bill of materials. Sealed zinc-coated collar note: VL065 covers the inner-ring bore and side faces under the -2RF seal set; the galvanized bore is slightly larger after coating, so use shafts in the lower half of the SKF tolerance band to avoid a skrink-fit that prevents collar removal. Collar geometry for this size: over the 19 mm outer-ring width the inner ring runs to 37.6 mm overall (51.1 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "one-direction conveyor drives", "ventilation equipment with frequent bearing changes", "agricultural machinery PTO-driven shafts" ], "failure_modes": [ "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 35 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 51.1 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Catalogue ratings belong to YEL 207-2RF/VL065 as the ecc two vl065 execution; other order numbers of the YEL 207 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-207-2RF-VL065?", "a": "The catalogue envelope is 35x72x37.6 mm with a spherical outside surface; mass 540 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 3,200 r/min." }, { "q": "What does the designation YEL 207-2RF/VL065 mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. VL065 adds zinc coating exactly where the inner ring meets the shaft and abutments; the rest of the bearing follows the standard design of the YEL2 size." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YELAG-207", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 207 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-207-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 207-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YELAG-207-106", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 207-106 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-207-106-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 207-106-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-207-2RF-VL065", "YEL 207-2RF/VL065" ], "locale_variants": {} }, { "sku": "YEL-207-2F", "brand": "SKF", "manufacturer_designation": "YEL 207-2F", "series": "YEL2-series", "type": "insert", "d_mm": 35, "D_mm": 72, "B_mm": 37.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 540, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YEL 207-2F is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 35x72x37.6 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 35x72x37.6 mm (1.378x2.835x1.48 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 51.1 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 540 g. At the printed limiting speed of 5,300 r/min the mean diameter dm = 53.5 mm implies dn about 2.84x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Load balance for documentation: C0 15.3 kN against C 25.5 kN gives a 0.6 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 35x72 mm insert on its chamfer tilts the whole spherical seat. Spherical-seat note in numbers: the 72 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 53.5 = 168.075 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. The s1 32.3 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Direction rule for YEL-207-2F: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 35 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "ventilation equipment with frequent bearing changes", "agricultural machinery PTO-driven shafts", "tiller and cultivator rotors" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 35 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 51.1 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Catalogue ratings belong to YEL 207-2F as the ecc two f execution; other order numbers of the YEL 207 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-207-2F?", "a": "The catalogue envelope is 35x72x37.6 mm with a spherical outside surface; mass 540 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 5,300 r/min." }, { "q": "What does the designation YEL 207-2F mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YELAG-207", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 207 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-207-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 207-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YELAG-207-106", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 207-106 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-207-106-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 207-106-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-207-2F", "YEL 207-2F" ], "locale_variants": {} }, { "sku": "YET-208", "brand": "SKF", "manufacturer_designation": "YET 208", "series": "YEL2-series", "type": "insert", "d_mm": 40, "D_mm": 80, "B_mm": 29.7, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YET 208 is SKF's 40 mm-bore eccentric-locking-collar insert bearing with a one-side-extended inner ring in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 40x80x29.7 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. this suffix-free execution is listed without the sealed external design: the 29.7 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals. Envelope 40x80x29.7 mm (1.575x3.15x1.169 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. Mounted width B1 43.2 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 4,800 r/min; mass 600 g. Imperial procurement cross-check: 1.575 in bore, 3.15 in OD, 1.169 in overall width; the 600 g mass converts to 0.600 kg (21.2 oz) for the bill of materials. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 40x80 mm insert on its chamfer tilts the whole spherical seat. At the printed limiting speed of 4,800 r/min the mean diameter dm = 60 mm implies dn about 2.88x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Bore-to-OD planning: OD 80 over bore 40 is a 2x step, while bore/overall-width gives 1.347; the spherical seat in the matching Y-housing must be specified to the 80 mm OD, not to a cylindrical housing bore. Spherical-seat note in numbers: the 80 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 60 = 188.496 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Collar geometry for this size: over the 21 mm outer-ring width the inner ring runs to 29.7 mm overall (43.2 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "agricultural machinery PTO-driven shafts", "tiller and cultivator rotors", "ventilation equipment with frequent bearing changes" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Overall width 43.2 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 40 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "The 30.7/19 kN figures belong specifically to YET 208; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-208?", "a": "YET 208 measures 40 mm bore x 80 mm OD x 29.7 mm overall width (outer ring 21 mm wide), 1.575 x 3.15 x 1.169 in; mass about 600 g. SKF 17000 ratings: C 30.7 kN, C0 19 kN, Pu 0.8 kN, limiting speed 4,800 r/min." }, { "q": "What does the designation YET 208 mean?", "a": "the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. this suffix-free execution is listed without the sealed external design: the 29.7 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YET-208-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x29.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 208/VL065 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-208", "YET 208" ], "locale_variants": {} }, { "sku": "YET-208-VL065", "brand": "SKF", "manufacturer_designation": "YET 208/VL065", "series": "YEL2-series", "type": "insert", "d_mm": 40, "D_mm": 80, "B_mm": 29.7, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YET 208/VL065 is a eccentric-locking-collar insert bearing with a one-side-extended inner ring, 40x80x29.7 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. VL065 adds zinc coating exactly where the inner ring meets the shaft and abutments; the rest of the bearing follows the standard design of the YEL2 size. Envelope 40x80x29.7 mm (1.575x3.15x1.169 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. Mounted width B1 43.2 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 4,800 r/min; mass 600 g. Spherical-seat note in numbers: the 80 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 60 = 188.496 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Capacity density: 30.7 kN from 0.600 kg of bearing steel is about 51.167 kN per kilogram, and per width millimetre the 29.7 mm unit carries 1.034 kN of dynamic capacity. Static-first planning: the 0.64 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 40 mm shaft, not the 30.7 kN L10 value. Bore-to-OD planning: OD 80 over bore 40 is a 2x step, while bore/overall-width gives 1.347; the spherical seat in the matching Y-housing must be specified to the 80 mm OD, not to a cylindrical housing bore. Rating split for the maintenance file: dynamic 30.7 kN (L10), static 19 kN (s0 shock check), fatigue 0.8 kN (adjusted life) — three separate uses for YET 208/VL065, none interchangeable with another. Zinc-coated one-side collar note: the VL065 layer protects the inner-ring bore and abutment faces; the eccentric collar itself is uncoated, so grease the collar-back interface to keep the zinc-free face from corroding fast to the inner ring. Direction rule for YET-208-VL065: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 40 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes", "tiller and cultivator rotors" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Overall width 43.2 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "The eccentric collar is handed to running direction; fit it wrong on the 40 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The 30.7/19 kN figures belong specifically to YET 208/VL065; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-208-VL065?", "a": "The catalogue envelope is 40x80x29.7 mm with a spherical outside surface; mass 600 g. Ratings C 30.7/19 kN, Pu 0.8 kN, limiting speed 4,800 r/min." }, { "q": "What does the designation YET 208/VL065 mean?", "a": "reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. VL065 adds zinc coating exactly where the inner ring meets the shaft and abutments; the rest of the bearing follows the standard design of the YEL2 size." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YET-208", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x29.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 208 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-208-VL065", "YET 208/VL065" ], "locale_variants": {} }, { "sku": "YELAG-208", "brand": "SKF", "manufacturer_designation": "YELAG 208", "series": "YEL2-series", "type": "insert", "d_mm": 40, "D_mm": 80, "B_mm": 42.8, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 950, "max_rpm": 950, "weight_g": 690, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YELAG 208 is a SKF insert bearing (Y-bearing) for a 40 mm shaft: eccentric-locking-collar insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 80 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution. Envelope 40x80x42.8 mm (1.575x3.15x1.685 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. Mounted width B1 56.3 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 950 r/min; mass 690 g. Outer-vs-overall width: the outer ring is 21 mm wide inside the 42.8 mm total, so the extended inner ring accounts for 0.509 of the overall width (10.9 mm of axial projection per side). Spherical-seat note in numbers: the 80 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 60 = 188.496 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Load balance for documentation: C0 19 kN against C 30.7 kN gives a 0.619 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Static-first planning: the 0.444 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 40 mm shaft, not the 30.7 kN L10 value. The s1 34.9 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Direction rule for YELAG-208: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 40 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "one-direction conveyor drives", "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes" ], "failure_modes": [ "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 40 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 56.3 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Catalogue ratings belong to YELAG 208 as the ecc two ag execution; other order numbers of the YELAG 208 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-208?", "a": "Boundary dimensions: bore 40 mm, sphered OD 80 mm, overall width 42.8 mm (56.3 mm with the collar); weight 690 g. Loads: dynamic 30.7 kN, static 19 kN, fatigue 0.8 kN; the only published speed is the 950 r/min limiting value." }, { "q": "What does the designation YELAG 208 mean?", "a": "YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YEL-208-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 208-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-208-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 208-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSPAG-208", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 208 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSP-208-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 208 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-208", "YELAG 208" ], "locale_variants": {} }, { "sku": "YEL-208-2RF-VL065", "brand": "SKF", "manufacturer_designation": "YEL 208-2RF/VL065", "series": "YEL2-series", "type": "insert", "d_mm": 40, "D_mm": 80, "B_mm": 42.8, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 710, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YEL 208-2RF/VL065 is a SKF insert bearing (Y-bearing) for a 40 mm shaft: eccentric-locking-collar insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 80 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the VL065 treatment galvanizes the bore and both side faces of the inner ring — a targeted anti-rust option for shafts and housings in damp air, used here with the printed seal execution. Envelope 40x80x42.8 mm (1.575x3.15x1.685 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. Mounted width B1 56.3 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 2,800 r/min; mass 710 g. Width accounting: B1 56.3 mm covers the bearing WITH its eccentric locking collar against 42.8 mm for the bearing itself and 21 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Bore-to-OD planning: OD 80 over bore 40 is a 2x step, while bore/overall-width gives 0.935; the spherical seat in the matching Y-housing must be specified to the 80 mm OD, not to a cylindrical housing bore. Pitch-diameter arithmetic: dm = (40+80)/2 = 60 mm; at the 2,800 r/min limiting speed the ball set runs at dn approx 1.68x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Load balance for documentation: C0 19 kN against C 30.7 kN gives a 0.619 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 40x80 mm insert on its chamfer tilts the whole spherical seat. Sealed zinc-coated collar note: VL065 covers the inner-ring bore and side faces under the -2RF seal set; the galvanized bore is slightly larger after coating, so use shafts in the lower half of the SKF tolerance band to avoid a skrink-fit that prevents collar removal. Direction rule for YEL-208-2RF-VL065: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 40 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "one-direction conveyor drives", "tiller and cultivator rotors", "agricultural machinery PTO-driven shafts" ], "failure_modes": [ "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 40 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 56.3 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Catalogue ratings belong to YEL 208-2RF/VL065 as the ecc two vl065 execution; other order numbers of the YEL 208 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-208-2RF-VL065?", "a": "Boundary dimensions: bore 40 mm, sphered OD 80 mm, overall width 42.8 mm (56.3 mm with the collar); weight 710 g. Loads: dynamic 30.7 kN, static 19 kN, fatigue 0.8 kN; the only published speed is the 2,800 r/min limiting value." }, { "q": "What does the designation YEL 208-2RF/VL065 mean?", "a": "YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the VL065 treatment galvanizes the bore and both side faces of the inner ring — a targeted anti-rust option for shafts and housings in damp air, used here with the printed seal execution." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YELAG-208", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 208 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-208-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 208-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSPAG-208", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 208 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSP-208-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 208 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-208-2RF-VL065", "YEL 208-2RF/VL065" ], "locale_variants": {} }, { "sku": "YEL-208-2F", "brand": "SKF", "manufacturer_designation": "YEL 208-2F", "series": "YEL2-series", "type": "insert", "d_mm": 40, "D_mm": 80, "B_mm": 42.8, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YEL 208-2F is a SKF insert bearing (Y-bearing) for a 40 mm shaft: eccentric-locking-collar insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 80 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 40x80x42.8 mm (1.575x3.15x1.685 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. Mounted width B1 56.3 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 4,800 r/min; mass 700 g. Pitch-diameter arithmetic: dm = (40+80)/2 = 60 mm; at the 4,800 r/min limiting speed the ball set runs at dn approx 2.88x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Speed ceiling of 4,800 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 40x80 mm insert on its chamfer tilts the whole spherical seat. Bore-to-OD planning: OD 80 over bore 40 is a 2x step, while bore/overall-width gives 0.935; the spherical seat in the matching Y-housing must be specified to the 80 mm OD, not to a cylindrical housing bore. Fatigue-limit check: Pu 0.8 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YEL 208-2F — most belt-driven mounted-unit loads sit comfortably under 2.606 % of C. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Direction rule for YEL-208-2F: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 40 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "tiller and cultivator rotors", "ventilation equipment with frequent bearing changes", "one-direction conveyor drives" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 40 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 56.3 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Ordering discipline for the 40 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-208-2F?", "a": "Boundary dimensions: bore 40 mm, sphered OD 80 mm, overall width 42.8 mm (56.3 mm with the collar); weight 700 g. Loads: dynamic 30.7 kN, static 19 kN, fatigue 0.8 kN; the only published speed is the 4,800 r/min limiting value." }, { "q": "What does the designation YEL 208-2F mean?", "a": "YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YELAG-208", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 208 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-208-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 208-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSPAG-208", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 208 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSP-208-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 208 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-208-2F", "YEL 208-2F" ], "locale_variants": {} }, { "sku": "YET-209", "brand": "SKF", "manufacturer_designation": "YET 209", "series": "YEL2-series", "type": "insert", "d_mm": 45, "D_mm": 85, "B_mm": 30.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 680, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YET 209 is a eccentric-locking-collar insert bearing with a one-side-extended inner ring, 45x85x30.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 45x85x30.2 mm (1.772x3.346x1.189 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. Mounted width B1 43.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 680 g. Pitch-diameter arithmetic: dm = (45+85)/2 = 65 mm; at the 4,300 r/min limiting speed the ball set runs at dn approx 2.79x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Outer-vs-overall width: the outer ring is 22 mm wide inside the 30.2 mm total, so the extended inner ring accounts for 0.272 of the overall width (8.2 mm of axial projection on the locking side). Bore-to-OD planning: OD 85 over bore 45 is a 1.889x step, while bore/overall-width gives 1.49; the spherical seat in the matching Y-housing must be specified to the 85 mm OD, not to a cylindrical housing bore. Mass-to-load ratio for YET-209: 20.482 g of catalogue mass per rated kN of C, and 15.111 g per millimetre of bore — useful when comparing executions of the same 45x85 mm envelope on the drawing. Fatigue-limit check: Pu 0.915 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YET 209 — most belt-driven mounted-unit loads sit comfortably under 2.756 % of C. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Direction rule for YET-209: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 45 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "tiller and cultivator rotors", "ventilation equipment with frequent bearing changes", "one-direction conveyor drives" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Overall width 43.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "The eccentric collar is handed to running direction; fit it wrong on the 45 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The 33.2/21.6 kN figures belong specifically to YET 209; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-209?", "a": "The catalogue envelope is 45x85x30.2 mm with a spherical outside surface; mass 680 g. Ratings C 33.2/21.6 kN, Pu 0.915 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YET 209 mean?", "a": "reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-209", "YET 209" ], "locale_variants": {} }, { "sku": "YELAG-209", "brand": "SKF", "manufacturer_designation": "YELAG 209", "series": "YEL2-series", "type": "insert", "d_mm": 45, "D_mm": 85, "B_mm": 42.8, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 850, "max_rpm": 850, "weight_g": 780, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YELAG 209 is a SKF insert bearing (Y-bearing) for a 45 mm shaft: eccentric-locking-collar insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 85 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution. Envelope 45x85x42.8 mm (1.772x3.346x1.685 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. Mounted width B1 56.3 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 850 r/min; mass 780 g. Load balance for documentation: C0 21.6 kN against C 33.2 kN gives a 0.651 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Rating split for the maintenance file: dynamic 33.2 kN (L10), static 21.6 kN (s0 shock check), fatigue 0.915 kN (adjusted life) — three separate uses for YELAG 209, none interchangeable with another. Bore-to-OD planning: OD 85 over bore 45 is a 1.889x step, while bore/overall-width gives 1.051; the spherical seat in the matching Y-housing must be specified to the 85 mm OD, not to a cylindrical housing bore. Envelope arithmetic: the radial section from 45 mm bore to 85 mm OD is 20 mm; dividing C 33.2 kN by that section gives 1.66 kN per section millimetre, and the 42.8 mm overall width is 2.14x the section. Speed ceiling of 850 r/min is the catalogue mechanical limit for THIS execution; the AG agricultural derate is deliberate, so real fan duty is planned well below it. Direction rule for YELAG-209: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 45 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "agricultural machinery PTO-driven shafts", "one-direction conveyor drives", "ventilation equipment with frequent bearing changes" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Overall width 56.3 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "The eccentric collar is handed to running direction; fit it wrong on the 45 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The 33.2/21.6 kN figures belong specifically to YELAG 209; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-209?", "a": "Boundary dimensions: bore 45 mm, sphered OD 85 mm, overall width 42.8 mm (56.3 mm with the collar); weight 780 g. Loads: dynamic 33.2 kN, static 21.6 kN, fatigue 0.915 kN; the only published speed is the 850 r/min limiting value." }, { "q": "What does the designation YELAG 209 mean?", "a": "YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YEL-209-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 45x85x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 209-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-209", "YELAG 209" ], "locale_variants": {} }, { "sku": "YEL-209-2F", "brand": "SKF", "manufacturer_designation": "YEL 209-2F", "series": "YEL2-series", "type": "insert", "d_mm": 45, "D_mm": 85, "B_mm": 42.8, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 790, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YEL 209-2F is SKF's 45 mm-bore eccentric-locking-collar insert bearing with the inner ring extended on both sides in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 45x85x42.8 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 45x85x42.8 mm (1.772x3.346x1.685 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. Mounted width B1 56.3 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 790 g. At the printed limiting speed of 4,300 r/min the mean diameter dm = 65 mm implies dn about 2.79x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Bore-to-OD planning: OD 85 over bore 45 is a 1.889x step, while bore/overall-width gives 1.051; the spherical seat in the matching Y-housing must be specified to the 85 mm OD, not to a cylindrical housing bore. The s1 34.9 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Static-first planning: the 0.505 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 45 mm shaft, not the 33.2 kN L10 value. Envelope arithmetic: the radial section from 45 mm bore to 85 mm OD is 20 mm; dividing C 33.2 kN by that section gives 1.66 kN per section millimetre, and the 42.8 mm overall width is 2.14x the section. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Direction rule for YEL-209-2F: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 45 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "ventilation equipment with frequent bearing changes", "tiller and cultivator rotors", "one-direction conveyor drives" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 56.3 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "The eccentric collar is handed to running direction; fit it wrong on the 45 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Ordering discipline for the 45 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-209-2F?", "a": "YEL 209-2F measures 45 mm bore x 85 mm OD x 42.8 mm overall width (outer ring 22 mm wide), 1.772 x 3.346 x 1.685 in; mass about 790 g. SKF 17000 ratings: C 33.2 kN, C0 21.6 kN, Pu 0.915 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YEL 209-2F mean?", "a": "the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YELAG-209", "equiv_brand": "SKF", "level": "full", "note": "Same 45x85x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 209 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-209-2F", "YEL 209-2F" ], "locale_variants": {} }, { "sku": "YET-210", "brand": "SKF", "manufacturer_designation": "YET 210", "series": "YEL2-series", "type": "insert", "d_mm": 50, "D_mm": 90, "B_mm": 30.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 740, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YET 210 is a eccentric-locking-collar insert bearing with a one-side-extended inner ring, 50x90x30.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 50x90x30.2 mm (1.969x3.543x1.189 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. Mounted width B1 43.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 4,000 r/min; mass 740 g. Speed ceiling of 4,000 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 62.5 mm, d2 67.2 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Width accounting: B1 43.7 mm covers the bearing WITH its eccentric locking collar against 30.2 mm for the bearing itself and 22 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. The s1 32.7 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Grease-life arithmetic is dominated by speed: at dn approx 2.80x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Collar geometry for this size: over the 22 mm outer-ring width the inner ring runs to 30.2 mm overall (43.7 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "one-direction conveyor drives", "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes" ], "failure_modes": [ "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Overall width 43.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "The eccentric collar is handed to running direction; fit it wrong on the 50 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The 35.1/23.2 kN figures belong specifically to YET 210; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-210?", "a": "The catalogue envelope is 50x90x30.2 mm with a spherical outside surface; mass 740 g. Ratings C 35.1/23.2 kN, Pu 0.98 kN, limiting speed 4,000 r/min." }, { "q": "What does the designation YET 210 mean?", "a": "reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-210", "YET 210" ], "locale_variants": {} }, { "sku": "YELAG-210", "brand": "SKF", "manufacturer_designation": "YELAG 210", "series": "YEL2-series", "type": "insert", "d_mm": 50, "D_mm": 90, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 800, "max_rpm": 800, "weight_g": 900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YELAG 210 is SKF's 50 mm-bore eccentric-locking-collar insert bearing with the inner ring extended on both sides in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 50x90x49.2 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant. Envelope 50x90x49.2 mm (1.969x3.543x1.937 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. Mounted width B1 62.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 800 r/min; mass 900 g. At the printed limiting speed of 800 r/min the mean diameter dm = 70 mm implies dn about 0.56x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Speed ceiling of 800 r/min is the catalogue mechanical limit for THIS execution; the AG agricultural derate is deliberate, so real fan duty is planned well below it. Selection figures for YELAG 210: C0/C is 0.661, Pu 0.98 kN is 2.792 % of the 35.1 kN dynamic rating, and the 900 g catalogue mass works out to roughly 18 g per millimetre of the 50 mm bore. Spherical-seat note in numbers: the 90 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 70 = 219.911 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Outer-vs-overall width: the outer ring is 22 mm wide inside the 49.2 mm total, so the extended inner ring accounts for 0.553 of the overall width (13.6 mm of axial projection per side). Collar geometry for this size: over the 22 mm outer-ring width the inner ring runs to 49.2 mm overall (62.7 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "ventilation equipment with frequent bearing changes", "tiller and cultivator rotors", "one-direction conveyor drives" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Overall width 62.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 50 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "The 35.1/23.2 kN figures belong specifically to YELAG 210; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-210?", "a": "YELAG 210 measures 50 mm bore x 90 mm OD x 49.2 mm overall width (outer ring 22 mm wide), 1.969 x 3.543 x 1.937 in; mass about 900 g. SKF 17000 ratings: C 35.1 kN, C0 23.2 kN, Pu 0.98 kN, limiting speed 800 r/min." }, { "q": "What does the designation YELAG 210 mean?", "a": "the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YEL-210-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 210-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-210", "YELAG 210" ], "locale_variants": {} }, { "sku": "YEL-210-2F", "brand": "SKF", "manufacturer_designation": "YEL 210-2F", "series": "YEL2-series", "type": "insert", "d_mm": 50, "D_mm": 90, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 920, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YEL 210-2F is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 50x90x49.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 50x90x49.2 mm (1.969x3.543x1.937 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. Mounted width B1 62.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 4,000 r/min; mass 920 g. Rating split for the maintenance file: dynamic 35.1 kN (L10), static 23.2 kN (s0 shock check), fatigue 0.98 kN (adjusted life) — three separate uses for YEL 210-2F, none interchangeable with another. Static-first planning: the 0.472 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 50 mm shaft, not the 35.1 kN L10 value. Envelope arithmetic: the radial section from 50 mm bore to 90 mm OD is 20 mm; dividing C 35.1 kN by that section gives 1.755 kN per section millimetre, and the 49.2 mm overall width is 2.46x the section. Load balance for documentation: C0 23.2 kN against C 35.1 kN gives a 0.661 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 50x90 mm insert on its chamfer tilts the whole spherical seat. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Direction rule for YEL-210-2F: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 50 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "ventilation equipment with frequent bearing changes", "agricultural machinery PTO-driven shafts", "tiller and cultivator rotors" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Overall width 62.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 50 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "The 35.1/23.2 kN figures belong specifically to YEL 210-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-210-2F?", "a": "The catalogue envelope is 50x90x49.2 mm with a spherical outside surface; mass 920 g. Ratings C 35.1/23.2 kN, Pu 0.98 kN, limiting speed 4,000 r/min." }, { "q": "What does the designation YEL 210-2F mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YELAG-210", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 210 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-210-2F", "YEL 210-2F" ], "locale_variants": {} }, { "sku": "YET-211", "brand": "SKF", "manufacturer_designation": "YET 211", "series": "YEL2-series", "type": "insert", "d_mm": 55, "D_mm": 100, "B_mm": 32.6, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 1050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YET 211 is a eccentric-locking-collar insert bearing with a one-side-extended inner ring, 55x100x32.6 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. the size code 211 carries the usual bore arithmetic — 55 mm (code 11 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 55x100x32.6 mm (2.165x3.937x1.283 in), outer ring 25 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. Mounted width B1 48.4 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 3,600 r/min; mass 1050 g. Capacity density: 43.6 kN from 1.050 kg of bearing steel is about 41.524 kN per kilogram, and per width millimetre the 32.6 mm unit carries 1.337 kN of dynamic capacity. Spherical-seat note in numbers: the 100 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 77.5 = 243.473 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Load balance for documentation: C0 29 kN against C 43.6 kN gives a 0.665 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Static-first planning: the 0.89 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 55 mm shaft, not the 43.6 kN L10 value. Grease-life arithmetic is dominated by speed: at dn approx 2.79x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Direction rule for YET-211: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 55 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "one-direction conveyor drives", "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes" ], "failure_modes": [ "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 55 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 48.4 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Catalogue ratings belong to YET 211 as the ecc one open execution; other order numbers of the YET 211 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-211?", "a": "The catalogue envelope is 55x100x32.6 mm with a spherical outside surface; mass 1050 g. Ratings C 43.6/29 kN, Pu 1.25 kN, limiting speed 3,600 r/min." }, { "q": "What does the designation YET 211 mean?", "a": "reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. the size code 211 carries the usual bore arithmetic — 55 mm (code 11 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-211", "YET 211" ], "locale_variants": {} }, { "sku": "YEL-211-2F", "brand": "SKF", "manufacturer_designation": "YEL 211-2F", "series": "YEL2-series", "type": "insert", "d_mm": 55, "D_mm": 100, "B_mm": 55.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YEL 211-2F is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 55x100x55.6 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. the size code 211 carries the usual bore arithmetic — 55 mm (code 11 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 55x100x55.6 mm (2.165x3.937x2.189 in), outer ring 25 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. Mounted width B1 71.4 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 3,600 r/min; mass 1300 g. Selection figures for YEL 211-2F: C0/C is 0.665, Pu 1.25 kN is 2.867 % of the 43.6 kN dynamic rating, and the 1300 g catalogue mass works out to roughly 23.636 g per millimetre of the 55 mm bore. Fatigue-limit check: Pu 1.25 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YEL 211-2F — most belt-driven mounted-unit loads sit comfortably under 2.867 % of C. The s1 43.6 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Rating split for the maintenance file: dynamic 43.6 kN (L10), static 29 kN (s0 shock check), fatigue 1.25 kN (adjusted life) — three separate uses for YEL 211-2F, none interchangeable with another. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 55x100 mm insert on its chamfer tilts the whole spherical seat. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Collar geometry for this size: over the 25 mm outer-ring width the inner ring runs to 55.6 mm overall (71.4 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "one-direction conveyor drives", "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes" ], "failure_modes": [ "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Overall width 71.4 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 55 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "The 43.6/29 kN figures belong specifically to YEL 211-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-211-2F?", "a": "The catalogue envelope is 55x100x55.6 mm with a spherical outside surface; mass 1300 g. Ratings C 43.6/29 kN, Pu 1.25 kN, limiting speed 3,600 r/min." }, { "q": "What does the designation YEL 211-2F mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. the size code 211 carries the usual bore arithmetic — 55 mm (code 11 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YAR-211-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 55x100x55.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 211-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-211-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 55x100x55.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 211-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-211-2F", "YEL 211-2F" ], "locale_variants": {} }, { "sku": "YET-212", "brand": "SKF", "manufacturer_designation": "YET 212", "series": "YEL2-series", "type": "insert", "d_mm": 60, "D_mm": 110, "B_mm": 36.7, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 36, "fatigue_load_limit_kN": 1.53, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YET 212 is a SKF insert bearing (Y-bearing) for a 60 mm shaft: eccentric-locking-collar insert bearing with a one-side-extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 110 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YET means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on one side. the size code 212 carries the usual bore arithmetic — 60 mm (code 12 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. with no -2F/-2RF suffix the order number denotes the open external execution of the YEL2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings. Envelope 60x110x36.7 mm (2.362x4.331x1.445 in), outer ring 26 mm wide, C 52.7 kN, C0 36 kN, Pu 1.53 kN. Mounted width B1 52.6 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 3,400 r/min; mass 1350 g. Load balance for documentation: C0 36 kN against C 52.7 kN gives a 0.683 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Selection figures for YET 212: C0/C is 0.683, Pu 1.53 kN is 2.903 % of the 52.7 kN dynamic rating, and the 1350 g catalogue mass works out to roughly 22.5 g per millimetre of the 60 mm bore. Bore-to-OD planning: OD 110 over bore 60 is a 1.833x step, while bore/overall-width gives 1.635; the spherical seat in the matching Y-housing must be specified to the 110 mm OD, not to a cylindrical housing bore. Fatigue-limit check: Pu 1.53 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YET 212 — most belt-driven mounted-unit loads sit comfortably under 2.903 % of C. Mass-to-load ratio for YET-212: 25.617 g of catalogue mass per rated kN of C, and 22.5 g per millimetre of bore — useful when comparing executions of the same 60x110 mm envelope on the drawing. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Direction rule for YET-212: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 60 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "heavy agricultural and harvesting equipment", "one-direction bulk conveyor shafts", "forestry and chipper drives" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 60 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 52.6 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Ordering discipline for the 60 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-212?", "a": "Boundary dimensions: bore 60 mm, sphered OD 110 mm, overall width 36.7 mm (52.6 mm with the collar); weight 1350 g. Loads: dynamic 52.7 kN, static 36 kN, fatigue 1.53 kN; the only published speed is the 3,400 r/min limiting value." }, { "q": "What does the designation YET 212 mean?", "a": "YET means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on one side. the size code 212 carries the usual bore arithmetic — 60 mm (code 12 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. with no -2F/-2RF suffix the order number denotes the open external execution of the YEL2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-212", "YET 212" ], "locale_variants": {} }, { "sku": "YEL-212-2F", "brand": "SKF", "manufacturer_designation": "YEL 212-2F", "series": "YEL2-series", "type": "insert", "d_mm": 60, "D_mm": 110, "B_mm": 61.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 36, "fatigue_load_limit_kN": 1.53, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YEL 212-2F is SKF's 60 mm-bore eccentric-locking-collar insert bearing with the inner ring extended on both sides in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 60x110x61.9 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the size code 212 carries the usual bore arithmetic — 60 mm (code 12 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 60x110x61.9 mm (2.362x4.331x2.437 in), outer ring 26 mm wide, C 52.7 kN, C0 36 kN, Pu 1.53 kN. Mounted width B1 77.8 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 3,400 r/min; mass 1700 g. Fatigue-limit check: Pu 1.53 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YEL 212-2F — most belt-driven mounted-unit loads sit comfortably under 2.903 % of C. Bore-to-OD planning: OD 110 over bore 60 is a 1.833x step, while bore/overall-width gives 0.969; the spherical seat in the matching Y-housing must be specified to the 110 mm OD, not to a cylindrical housing bore. The s1 46.8 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Static-first planning: the 0.582 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 60 mm shaft, not the 52.7 kN L10 value. Speed ceiling of 3,400 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Direction rule for YEL-212-2F: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 60 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "heavy agricultural and harvesting equipment", "one-direction bulk conveyor shafts", "forestry and chipper drives" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 60 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 77.8 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Catalogue ratings belong to YEL 212-2F as the ecc two f execution; other order numbers of the YEL 212 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-212-2F?", "a": "YEL 212-2F measures 60 mm bore x 110 mm OD x 61.9 mm overall width (outer ring 26 mm wide), 2.362 x 4.331 x 2.437 in; mass about 1700 g. SKF 17000 ratings: C 52.7 kN, C0 36 kN, Pu 1.53 kN, limiting speed 3,400 r/min." }, { "q": "What does the designation YEL 212-2F mean?", "a": "the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the size code 212 carries the usual bore arithmetic — 60 mm (code 12 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YEL", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-212-2F", "YEL 212-2F" ], "locale_variants": {} }, { "sku": "YET-203-008", "brand": "SKF", "manufacturer_designation": "YET 203-008", "series": "YEL2-series", "type": "insert", "d_mm": 12.7, "D_mm": 40, "B_mm": 19.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 9.56, "static_load_kN": 4.75, "fatigue_load_limit_kN": 0.2, "limiting_speed_rpm": 9500, "max_rpm": 9500, "weight_g": 130, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YET 203-008 is a SKF insert bearing (Y-bearing) for a 12.7 mm (0.5 in) shaft: eccentric-locking-collar insert bearing with a one-side-extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 40 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YET means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on one side. inch bore code -008 decodes as 0\" +8/16, i.e. 12.7 mm; the metric coded size YET 203 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YEL2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings. Envelope 12.7x40x19.1 mm (0.5x1.575x0.752 in), outer ring 12 mm wide, C 9.56 kN, C0 4.75 kN, Pu 0.2 kN. Mounted width B1 28.6 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 9,500 r/min; mass 130 g. Mass-to-load ratio for YET-203-008: 13.598 g of catalogue mass per rated kN of C, and 10.236 g per millimetre of bore — useful when comparing executions of the same 12.7x40 mm envelope on the drawing. Width accounting: B1 28.6 mm covers the bearing WITH its eccentric locking collar against 19.1 mm for the bearing itself and 12 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Envelope arithmetic: the radial section from 12.7 mm bore to 40 mm OD is 13.65 mm; dividing C 9.56 kN by that section gives 0.7 kN per section millimetre, and the 19.1 mm overall width is 1.399x the section. Load balance for documentation: C0 4.75 kN against C 9.56 kN gives a 0.497 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Rating split for the maintenance file: dynamic 9.56 kN (L10), static 4.75 kN (s0 shock check), fatigue 0.2 kN (adjusted life) — three separate uses for YET 203-008, none interchangeable with another. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Collar geometry for this size: over the 12 mm outer-ring width the inner ring runs to 19.1 mm overall (28.6 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "light drive rollers with plain commercial shafts", "small garden machinery and rotavators", "lawn and turf equipment" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 12.7 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 28.6 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Catalogue ratings belong to YET 203-008 as the ecc one open execution; other order numbers of the YET 203-008 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-203-008?", "a": "Boundary dimensions: bore 12.7 mm, sphered OD 40 mm, overall width 19.1 mm (28.6 mm with the collar); weight 130 g. Loads: dynamic 9.56 kN, static 4.75 kN, fatigue 0.2 kN; the only published speed is the 9,500 r/min limiting value." }, { "q": "What does the designation YET 203-008 mean?", "a": "YET means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on one side. inch bore code -008 decodes as 0\" +8/16, i.e. 12.7 mm; the metric coded size YET 203 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YEL2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-203-008", "YET 203-008" ], "locale_variants": {} }, { "sku": "YET-204-012", "brand": "SKF", "manufacturer_designation": "YET 204-012", "series": "YEL2-series", "type": "insert", "d_mm": 19.049999999999997, "D_mm": 47, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 170, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YET 204-012 is SKF's 19.049999999999997 mm-bore eccentric-locking-collar insert bearing with a one-side-extended inner ring in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 19.049999999999997x47x21 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the three-digit -012 tail codes the bore in inches for inch-shaft bearings: 0 whole inch 12/16 in = 19.05 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 21 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals. Envelope 19.049999999999997x47x21 mm (0.75x1.85x0.827 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. Mounted width B1 30.5 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 8,500 r/min; mass 170 g. Selection figures for YET 204-012: C0/C is 0.516, Pu 0.28 kN is 2.205 % of the 12.7 kN dynamic rating, and the 170 g catalogue mass works out to roughly 8.924 g per millimetre of the 19.049999999999997 mm bore. The s1 23.5 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Spherical-seat note in numbers: the 47 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 33.025 = 103.751 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Load balance for documentation: C0 6.55 kN against C 12.7 kN gives a 0.516 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Static-first planning: the 0.312 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 19.049999999999997 mm shaft, not the 12.7 kN L10 value. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Direction rule for YET-204-012: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 19.049999999999997 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "lawn and turf equipment", "light drive rollers with plain commercial shafts", "small garden machinery and rotavators" ], "failure_modes": [ "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Overall width 30.5 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 19.049999999999997 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "The 12.7/6.55 kN figures belong specifically to YET 204-012; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-204-012?", "a": "YET 204-012 measures 19.049999999999997 mm bore x 47 mm OD x 21 mm overall width (outer ring 14 mm wide), 0.75 x 1.85 x 0.827 in; mass about 170 g. SKF 17000 ratings: C 12.7 kN, C0 6.55 kN, Pu 0.28 kN, limiting speed 8,500 r/min." }, { "q": "What does the designation YET 204-012 mean?", "a": "the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the three-digit -012 tail codes the bore in inches for inch-shaft bearings: 0 whole inch 12/16 in = 19.05 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 21 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-204-012", "YET 204-012" ], "locale_variants": {} }, { "sku": "YEL-204-012-2F", "brand": "SKF", "manufacturer_designation": "YEL 204-012-2F", "series": "YEL2-series", "type": "insert", "d_mm": 19.049999999999997, "D_mm": 47, "B_mm": 34.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 210, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YEL 204-012-2F is SKF's 19.049999999999997 mm-bore eccentric-locking-collar insert bearing with the inner ring extended on both sides in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 19.049999999999997x47x34.2 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the three-digit -012 tail codes the bore in inches for inch-shaft bearings: 0 whole inch 12/16 in = 19.05 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 19.049999999999997x47x34.2 mm (0.75x1.85x1.346 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. Mounted width B1 43.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 8,500 r/min; mass 210 g. Static-first planning: the 0.192 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 19.049999999999997 mm shaft, not the 12.7 kN L10 value. Grease-life arithmetic is dominated by speed: at dn approx 2.81x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Pitch-diameter arithmetic: dm = (19.049999999999997+47)/2 = 33.025 mm; at the 8,500 r/min limiting speed the ball set runs at dn approx 2.81x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Bore-to-OD planning: OD 47 over bore 19.049999999999997 is a 2.467x step, while bore/overall-width gives 0.557; the spherical seat in the matching Y-housing must be specified to the 47 mm OD, not to a cylindrical housing bore. Selection figures for YEL 204-012-2F: C0/C is 0.516, Pu 0.28 kN is 2.205 % of the 12.7 kN dynamic rating, and the 210 g catalogue mass works out to roughly 11.024 g per millimetre of the 19.049999999999997 mm bore. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Direction rule for YEL-204-012-2F: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 19.049999999999997 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "small garden machinery and rotavators", "lawn and turf equipment", "light drive rollers with plain commercial shafts" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 19.049999999999997 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 43.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Catalogue ratings belong to YEL 204-012-2F as the ecc two f execution; other order numbers of the YEL 204-012 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-204-012-2F?", "a": "YEL 204-012-2F measures 19.049999999999997 mm bore x 47 mm OD x 34.2 mm overall width (outer ring 14 mm wide), 0.75 x 1.85 x 1.346 in; mass about 210 g. SKF 17000 ratings: C 12.7 kN, C0 6.55 kN, Pu 0.28 kN, limiting speed 8,500 r/min." }, { "q": "What does the designation YEL 204-012-2F mean?", "a": "the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the three-digit -012 tail codes the bore in inches for inch-shaft bearings: 0 whole inch 12/16 in = 19.05 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YEL", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-204-012-2F", "YEL 204-012-2F" ], "locale_variants": {} }, { "sku": "YET-205-100", "brand": "SKF", "manufacturer_designation": "YET 205-100", "series": "YEL2-series", "type": "insert", "d_mm": 25.4, "D_mm": 52, "B_mm": 21.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YET 205-100 is a eccentric-locking-collar insert bearing with a one-side-extended inner ring, 25.4x52x21.5 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -100 = 25.4 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 25.4x52x21.5 mm (1x2.047x0.846 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. Mounted width B1 31 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 7,000 r/min; mass 190 g. The s1 23.5 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Rating split for the maintenance file: dynamic 14 kN (L10), static 7.8 kN (s0 shock check), fatigue 0.335 kN (adjusted life) — three separate uses for YET 205-100, none interchangeable with another. Envelope arithmetic: the radial section from 25.4 mm bore to 52 mm OD is 13.3 mm; dividing C 14 kN by that section gives 1.053 kN per section millimetre, and the 21.5 mm overall width is 1.617x the section. Pitch-diameter arithmetic: dm = (25.4+52)/2 = 38.7 mm; at the 7,000 r/min limiting speed the ball set runs at dn approx 2.71x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Speed ceiling of 7,000 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Direction rule for YET-205-100: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 25.4 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "agricultural machinery PTO-driven shafts", "one-direction conveyor drives", "ventilation equipment with frequent bearing changes" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Overall width 31 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "The eccentric collar is handed to running direction; fit it wrong on the 25.4 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The 14/7.8 kN figures belong specifically to YET 205-100; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-205-100?", "a": "The catalogue envelope is 25.4x52x21.5 mm with a spherical outside surface; mass 190 g. Ratings C 14/7.8 kN, Pu 0.335 kN, limiting speed 7,000 r/min." }, { "q": "What does the designation YET 205-100 mean?", "a": "reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -100 = 25.4 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YET-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x21.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 205 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YET-205-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x21.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 205/VL065 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-205-100", "YET 205-100" ], "locale_variants": {} }, { "sku": "YELAG-205-100", "brand": "SKF", "manufacturer_designation": "YELAG 205-100", "series": "YEL2-series", "type": "insert", "d_mm": 25.4, "D_mm": 52, "B_mm": 34.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 1500, "max_rpm": 1500, "weight_g": 230, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YELAG 205-100 is a SKF insert bearing (Y-bearing) for a 25.4 mm (1 in) shaft: eccentric-locking-collar insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 52 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -100 decodes as 1\", i.e. 25.4 mm; the metric coded size YELAG 205 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution. Envelope 25.4x52x34.9 mm (1x2.047x1.374 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. Mounted width B1 44.4 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 1,500 r/min; mass 230 g. Imperial procurement cross-check: 1 in bore, 2.047 in OD, 1.374 in overall width; the 230 g mass converts to 0.230 kg (8.1 oz) for the bill of materials. Selection figures for YELAG 205-100: C0/C is 0.557, Pu 0.335 kN is 2.393 % of the 14 kN dynamic rating, and the 230 g catalogue mass works out to roughly 9.055 g per millimetre of the 25.4 mm bore. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 25.4x52 mm insert on its chamfer tilts the whole spherical seat. At the printed limiting speed of 1,500 r/min the mean diameter dm = 38.7 mm implies dn about 0.58x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Pitch-diameter arithmetic: dm = (25.4+52)/2 = 38.7 mm; at the 1,500 r/min limiting speed the ball set runs at dn approx 0.58x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Direction rule for YELAG-205-100: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 25.4 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes", "tiller and cultivator rotors" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Overall width 44.4 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "The eccentric collar is handed to running direction; fit it wrong on the 25.4 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The 14/7.8 kN figures belong specifically to YELAG 205-100; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-205-100?", "a": "Boundary dimensions: bore 25.4 mm, sphered OD 52 mm, overall width 34.9 mm (44.4 mm with the collar); weight 230 g. Loads: dynamic 14 kN, static 7.8 kN, fatigue 0.335 kN; the only published speed is the 1,500 r/min limiting value." }, { "q": "What does the designation YELAG 205-100 mean?", "a": "YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -100 decodes as 1\", i.e. 25.4 mm; the metric coded size YELAG 205 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YELAG-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 205 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-205-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 205-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-205-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 205-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-205-100-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 205-100-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-205-100", "YELAG 205-100" ], "locale_variants": {} }, { "sku": "YEL-205-100-2F", "brand": "SKF", "manufacturer_designation": "YEL 205-100-2F", "series": "YEL2-series", "type": "insert", "d_mm": 25.4, "D_mm": 52, "B_mm": 34.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YEL 205-100-2F is a SKF insert bearing (Y-bearing) for a 25.4 mm (1 in) shaft: eccentric-locking-collar insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 52 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -100 decodes as 1\", i.e. 25.4 mm; the metric coded size YEL 205 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 25.4x52x34.9 mm (1x2.047x1.374 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. Mounted width B1 44.4 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 7,000 r/min; mass 240 g. Bore-to-OD planning: OD 52 over bore 25.4 is a 2.047x step, while bore/overall-width gives 0.728; the spherical seat in the matching Y-housing must be specified to the 52 mm OD, not to a cylindrical housing bore. Static-first planning: the 0.223 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 25.4 mm shaft, not the 14 kN L10 value. Rating split for the maintenance file: dynamic 14 kN (L10), static 7.8 kN (s0 shock check), fatigue 0.335 kN (adjusted life) — three separate uses for YEL 205-100-2F, none interchangeable with another. Speed ceiling of 7,000 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Spherical-seat note in numbers: the 52 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 38.7 = 121.58 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Collar geometry for this size: over the 15 mm outer-ring width the inner ring runs to 34.9 mm overall (44.4 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "tiller and cultivator rotors", "agricultural machinery PTO-driven shafts", "one-direction conveyor drives" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 25.4 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 44.4 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Catalogue ratings belong to YEL 205-100-2F as the ecc two f execution; other order numbers of the YEL 205-100 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-205-100-2F?", "a": "Boundary dimensions: bore 25.4 mm, sphered OD 52 mm, overall width 34.9 mm (44.4 mm with the collar); weight 240 g. Loads: dynamic 14 kN, static 7.8 kN, fatigue 0.335 kN; the only published speed is the 7,000 r/min limiting value." }, { "q": "What does the designation YEL 205-100-2F mean?", "a": "YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -100 decodes as 1\", i.e. 25.4 mm; the metric coded size YEL 205 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YELAG-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 205 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-205-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 205-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-205-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 205-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YELAG-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x34.9 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 205-100 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-205-100-2F", "YEL 205-100-2F" ], "locale_variants": {} }, { "sku": "YET-206-102", "brand": "SKF", "manufacturer_designation": "YET 206-102", "series": "YEL2-series", "type": "insert", "d_mm": 28.575, "D_mm": 62, "B_mm": 23.8, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 340, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YET 206-102 is a eccentric-locking-collar insert bearing with a one-side-extended inner ring, 28.575x62x23.8 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -102 = 28.575 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 28.575x62x23.8 mm (1.125x2.441x0.937 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. Mounted width B1 35.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 340 g. The s1 26.7 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Load balance for documentation: C0 11.2 kN against C 19.5 kN gives a 0.574 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Outer-vs-overall width: the outer ring is 18 mm wide inside the 23.8 mm total, so the extended inner ring accounts for 0.244 of the overall width (5.8 mm of axial projection on the locking side). Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 28.575x62 mm insert on its chamfer tilts the whole spherical seat. Envelope arithmetic: the radial section from 28.575 mm bore to 62 mm OD is 16.712 mm; dividing C 19.5 kN by that section gives 1.167 kN per section millimetre, and the 23.8 mm overall width is 1.424x the section. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Collar geometry for this size: over the 18 mm outer-ring width the inner ring runs to 23.8 mm overall (35.7 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes", "tiller and cultivator rotors" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 28.575 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 35.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Ordering discipline for the 28.575 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-206-102?", "a": "The catalogue envelope is 28.575x62x23.8 mm with a spherical outside surface; mass 340 g. Ratings C 19.5/11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YET 206-102 mean?", "a": "reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -102 = 28.575 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-206-102", "YET 206-102" ], "locale_variants": {} }, { "sku": "YELAG-206-102", "brand": "SKF", "manufacturer_designation": "YELAG 206-102", "series": "YEL2-series", "type": "insert", "d_mm": 28.575, "D_mm": 62, "B_mm": 36.5, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 1200, "max_rpm": 1200, "weight_g": 400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YELAG 206-102 is SKF's 28.575 mm-bore eccentric-locking-collar insert bearing with the inner ring extended on both sides in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 28.575x62x36.5 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the three-digit -102 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 2/16 in = 28.575 mm (first digit whole inches, next two sixteenths of an inch). AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant. Envelope 28.575x62x36.5 mm (1.125x2.441x1.437 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. Mounted width B1 48.4 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 1,200 r/min; mass 400 g. Pitch-diameter arithmetic: dm = (28.575+62)/2 = 45.288 mm; at the 1,200 r/min limiting speed the ball set runs at dn approx 0.54x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Capacity density: 19.5 kN from 0.400 kg of bearing steel is about 48.75 kN per kilogram, and per width millimetre the 36.5 mm unit carries 0.534 kN of dynamic capacity. Spherical-seat note in numbers: the 62 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 45.288 = 142.276 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fatigue-limit check: Pu 0.475 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YELAG 206-102 — most belt-driven mounted-unit loads sit comfortably under 2.436 % of C. Mass-to-load ratio for YELAG-206-102: 20.513 g of catalogue mass per rated kN of C, and 13.998 g per millimetre of bore — useful when comparing executions of the same 28.575x62 mm envelope on the drawing. Collar geometry for this size: over the 18 mm outer-ring width the inner ring runs to 36.5 mm overall (48.4 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "tiller and cultivator rotors", "one-direction conveyor drives", "agricultural machinery PTO-driven shafts" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Overall width 48.4 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 28.575 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "The 19.5/11.2 kN figures belong specifically to YELAG 206-102; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-206-102?", "a": "YELAG 206-102 measures 28.575 mm bore x 62 mm OD x 36.5 mm overall width (outer ring 18 mm wide), 1.125 x 2.441 x 1.437 in; mass about 400 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 1,200 r/min." }, { "q": "What does the designation YELAG 206-102 mean?", "a": "the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the three-digit -102 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 2/16 in = 28.575 mm (first digit whole inches, next two sixteenths of an inch). AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YEL-206-102-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 28.575x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 206-102-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-206-102", "YELAG 206-102" ], "locale_variants": {} }, { "sku": "YEL-206-102-2F", "brand": "SKF", "manufacturer_designation": "YEL 206-102-2F", "series": "YEL2-series", "type": "insert", "d_mm": 28.575, "D_mm": 62, "B_mm": 36.5, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 410, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YEL 206-102-2F is a SKF insert bearing (Y-bearing) for a 28.575 mm (1.125 in) shaft: eccentric-locking-collar insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 62 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -102 decodes as 1\" +2/16, i.e. 28.575 mm; the metric coded size YEL 206 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 28.575x62x36.5 mm (1.125x2.441x1.437 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. Mounted width B1 48.4 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 410 g. Static-first planning: the 0.307 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 28.575 mm shaft, not the 19.5 kN L10 value. At the printed limiting speed of 6,300 r/min the mean diameter dm = 45.288 mm implies dn about 2.85x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Mass-to-load ratio for YEL-206-102-2F: 21.026 g of catalogue mass per rated kN of C, and 14.348 g per millimetre of bore — useful when comparing executions of the same 28.575x62 mm envelope on the drawing. Width accounting: B1 48.4 mm covers the bearing WITH its eccentric locking collar against 36.5 mm for the bearing itself and 18 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Load balance for documentation: C0 11.2 kN against C 19.5 kN gives a 0.574 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Direction rule for YEL-206-102-2F: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 28.575 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "agricultural machinery PTO-driven shafts", "one-direction conveyor drives", "ventilation equipment with frequent bearing changes" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 28.575 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 48.4 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Ordering discipline for the 28.575 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-206-102-2F?", "a": "Boundary dimensions: bore 28.575 mm, sphered OD 62 mm, overall width 36.5 mm (48.4 mm with the collar); weight 410 g. Loads: dynamic 19.5 kN, static 11.2 kN, fatigue 0.475 kN; the only published speed is the 6,300 r/min limiting value." }, { "q": "What does the designation YEL 206-102-2F mean?", "a": "YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -102 decodes as 1\" +2/16, i.e. 28.575 mm; the metric coded size YEL 206 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YELAG-206-102", "equiv_brand": "SKF", "level": "full", "note": "Same 28.575x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 206-102 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-206-102-2F", "YEL 206-102-2F" ], "locale_variants": {} }, { "sku": "YET-206-103", "brand": "SKF", "manufacturer_designation": "YET 206-103", "series": "YEL2-series", "type": "insert", "d_mm": 30.162499999999998, "D_mm": 62, "B_mm": 23.8, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 320, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YET 206-103 is SKF's 30.162499999999998 mm-bore eccentric-locking-collar insert bearing with a one-side-extended inner ring in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 30.162499999999998x62x23.8 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the three-digit -103 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 3/16 in = 30.162 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 23.8 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals. Envelope 30.162499999999998x62x23.8 mm (1.188x2.441x0.937 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. Mounted width B1 35.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 320 g. The s1 26.7 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 39.7 mm, d2 44.1 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Pitch-diameter arithmetic: dm = (30.162499999999998+62)/2 = 46.081 mm; at the 6,300 r/min limiting speed the ball set runs at dn approx 2.90x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Selection figures for YET 206-103: C0/C is 0.574, Pu 0.475 kN is 2.436 % of the 19.5 kN dynamic rating, and the 320 g catalogue mass works out to roughly 10.609 g per millimetre of the 30.162499999999998 mm bore. Imperial procurement cross-check: 1.188 in bore, 2.441 in OD, 0.937 in overall width; the 320 g mass converts to 0.320 kg (11.3 oz) for the bill of materials. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Direction rule for YET-206-103: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 30.162499999999998 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "agricultural machinery PTO-driven shafts", "one-direction conveyor drives", "ventilation equipment with frequent bearing changes" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 30.162499999999998 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 35.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Catalogue ratings belong to YET 206-103 as the ecc one open execution; other order numbers of the YET 206-103 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-206-103?", "a": "YET 206-103 measures 30.162499999999998 mm bore x 62 mm OD x 23.8 mm overall width (outer ring 18 mm wide), 1.188 x 2.441 x 0.937 in; mass about 320 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YET 206-103 mean?", "a": "the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the three-digit -103 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 3/16 in = 30.162 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 23.8 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YET-206", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x23.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 206 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YET-206-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x23.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 206/VL065 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-206-103", "YET 206-103" ], "locale_variants": {} }, { "sku": "YELAG-206-103", "brand": "SKF", "manufacturer_designation": "YELAG 206-103", "series": "YEL2-series", "type": "insert", "d_mm": 30.162499999999998, "D_mm": 62, "B_mm": 36.5, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 1200, "max_rpm": 1200, "weight_g": 370, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YELAG 206-103 is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 30.162499999999998x62x36.5 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -103 = 30.162 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 30.162499999999998x62x36.5 mm (1.188x2.441x1.437 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. Mounted width B1 48.4 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 1,200 r/min; mass 370 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 39.7 mm, d2 44.1 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Outer-vs-overall width: the outer ring is 18 mm wide inside the 36.5 mm total, so the extended inner ring accounts for 0.507 of the overall width (9.25 mm of axial projection per side). Imperial procurement cross-check: 1.188 in bore, 2.441 in OD, 1.437 in overall width; the 370 g mass converts to 0.370 kg (13.1 oz) for the bill of materials. Selection figures for YELAG 206-103: C0/C is 0.574, Pu 0.475 kN is 2.436 % of the 19.5 kN dynamic rating, and the 370 g catalogue mass works out to roughly 12.267 g per millimetre of the 30.162499999999998 mm bore. Envelope arithmetic: the radial section from 30.162499999999998 mm bore to 62 mm OD is 15.919 mm; dividing C 19.5 kN by that section gives 1.225 kN per section millimetre, and the 36.5 mm overall width is 2.293x the section. Collar geometry for this size: over the 18 mm outer-ring width the inner ring runs to 36.5 mm overall (48.4 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "ventilation equipment with frequent bearing changes", "tiller and cultivator rotors", "one-direction conveyor drives" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 48.4 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "The eccentric collar is handed to running direction; fit it wrong on the 30.162499999999998 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Ordering discipline for the 30.162499999999998 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-206-103?", "a": "The catalogue envelope is 30.162499999999998x62x36.5 mm with a spherical outside surface; mass 370 g. Ratings C 19.5/11.2 kN, Pu 0.475 kN, limiting speed 1,200 r/min." }, { "q": "What does the designation YELAG 206-103 mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -103 = 30.162 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YELAG-206", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 206 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-206-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 206-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-206-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 206-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-206-103-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 206-103-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-206-103", "YELAG 206-103" ], "locale_variants": {} }, { "sku": "YEL-206-103-2F", "brand": "SKF", "manufacturer_designation": "YEL 206-103-2F", "series": "YEL2-series", "type": "insert", "d_mm": 30.162499999999998, "D_mm": 62, "B_mm": 36.5, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 380, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YEL 206-103-2F is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 30.162499999999998x62x36.5 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -103 = 30.162 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 30.162499999999998x62x36.5 mm (1.188x2.441x1.437 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. Mounted width B1 48.4 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 380 g. Load balance for documentation: C0 11.2 kN against C 19.5 kN gives a 0.574 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Selection figures for YEL 206-103-2F: C0/C is 0.574, Pu 0.475 kN is 2.436 % of the 19.5 kN dynamic rating, and the 380 g catalogue mass works out to roughly 12.598 g per millimetre of the 30.162499999999998 mm bore. Mass-to-load ratio for YEL-206-103-2F: 19.487 g of catalogue mass per rated kN of C, and 12.598 g per millimetre of bore — useful when comparing executions of the same 30.162499999999998x62 mm envelope on the drawing. Bore-to-OD planning: OD 62 over bore 30.162499999999998 is a 2.056x step, while bore/overall-width gives 0.826; the spherical seat in the matching Y-housing must be specified to the 62 mm OD, not to a cylindrical housing bore. Speed ceiling of 6,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Collar geometry for this size: over the 18 mm outer-ring width the inner ring runs to 36.5 mm overall (48.4 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes", "tiller and cultivator rotors" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 30.162499999999998 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 48.4 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Catalogue ratings belong to YEL 206-103-2F as the ecc two f execution; other order numbers of the YEL 206-103 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-206-103-2F?", "a": "The catalogue envelope is 30.162499999999998x62x36.5 mm with a spherical outside surface; mass 380 g. Ratings C 19.5/11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YEL 206-103-2F mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -103 = 30.162 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YELAG-206", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 206 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-206-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 206-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-206-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 206-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YELAG-206-103", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x36.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 206-103 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-206-103-2F", "YEL 206-103-2F" ], "locale_variants": {} }, { "sku": "YET-206-104", "brand": "SKF", "manufacturer_designation": "YET 206-104", "series": "YEL2-series", "type": "insert", "d_mm": 31.75, "D_mm": 62, "B_mm": 23.8, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YET 206-104 is SKF's 31.75 mm-bore eccentric-locking-collar insert bearing with a one-side-extended inner ring in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 31.75x62x23.8 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the three-digit -104 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 4/16 in = 31.75 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 23.8 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals. Envelope 31.75x62x23.8 mm (1.25x2.441x0.937 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. Mounted width B1 35.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 300 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 39.7 mm, d2 44.1 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 31.75x62 mm insert on its chamfer tilts the whole spherical seat. Spherical-seat note in numbers: the 62 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 46.875 = 147.262 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Static-first planning: the 0.471 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 31.75 mm shaft, not the 19.5 kN L10 value. Capacity density: 19.5 kN from 0.300 kg of bearing steel is about 65 kN per kilogram, and per width millimetre the 23.8 mm unit carries 0.819 kN of dynamic capacity. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Direction rule for YET-206-104: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 31.75 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "ventilation equipment with frequent bearing changes", "tiller and cultivator rotors", "one-direction conveyor drives" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 31.75 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 35.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Ordering discipline for the 31.75 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-206-104?", "a": "YET 206-104 measures 31.75 mm bore x 62 mm OD x 23.8 mm overall width (outer ring 18 mm wide), 1.25 x 2.441 x 0.937 in; mass about 300 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YET 206-104 mean?", "a": "the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the three-digit -104 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 4/16 in = 31.75 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 23.8 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-206-104", "YET 206-104" ], "locale_variants": {} }, { "sku": "YET-207-104", "brand": "SKF", "manufacturer_designation": "YET 207-104", "series": "YEL2-series", "type": "insert", "d_mm": 31.75, "D_mm": 72, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 510, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YET 207-104 is a eccentric-locking-collar insert bearing with a one-side-extended inner ring, 31.75x72x25.4 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -104 = 31.75 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 31.75x72x25.4 mm (1.25x2.835x1 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 38.9 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 510 g. Mass-to-load ratio for YET-207-104: 20 g of catalogue mass per rated kN of C, and 16.063 g per millimetre of bore — useful when comparing executions of the same 31.75x72 mm envelope on the drawing. Capacity density: 25.5 kN from 0.510 kg of bearing steel is about 50 kN per kilogram, and per width millimetre the 25.4 mm unit carries 1.004 kN of dynamic capacity. Envelope arithmetic: the radial section from 31.75 mm bore to 72 mm OD is 20.125 mm; dividing C 25.5 kN by that section gives 1.267 kN per section millimetre, and the 25.4 mm overall width is 1.262x the section. Rating split for the maintenance file: dynamic 25.5 kN (L10), static 15.3 kN (s0 shock check), fatigue 0.655 kN (adjusted life) — three separate uses for YET 207-104, none interchangeable with another. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 31.75x72 mm insert on its chamfer tilts the whole spherical seat. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Direction rule for YET-207-104: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 31.75 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "tiller and cultivator rotors", "ventilation equipment with frequent bearing changes", "one-direction conveyor drives" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 31.75 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 38.9 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Catalogue ratings belong to YET 207-104 as the ecc one open execution; other order numbers of the YET 207-104 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-207-104?", "a": "The catalogue envelope is 31.75x72x25.4 mm with a spherical outside surface; mass 510 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 5,300 r/min." }, { "q": "What does the designation YET 207-104 mean?", "a": "reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -104 = 31.75 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-207-104", "YET 207-104" ], "locale_variants": {} }, { "sku": "YELAG-207-104", "brand": "SKF", "manufacturer_designation": "YELAG 207-104", "series": "YEL2-series", "type": "insert", "d_mm": 31.75, "D_mm": 72, "B_mm": 37.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YELAG 207-104 is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 31.75x72x37.6 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -104 = 31.75 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 31.75x72x37.6 mm (1.25x2.835x1.48 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 51.1 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 1,100 r/min; mass 600 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 46.1 mm, d2 51.1 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Fatigue-limit check: Pu 0.655 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YELAG 207-104 — most belt-driven mounted-unit loads sit comfortably under 2.569 % of C. Rating split for the maintenance file: dynamic 25.5 kN (L10), static 15.3 kN (s0 shock check), fatigue 0.655 kN (adjusted life) — three separate uses for YELAG 207-104, none interchangeable with another. The s1 32.3 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Envelope arithmetic: the radial section from 31.75 mm bore to 72 mm OD is 20.125 mm; dividing C 25.5 kN by that section gives 1.267 kN per section millimetre, and the 37.6 mm overall width is 1.868x the section. Collar geometry for this size: over the 19 mm outer-ring width the inner ring runs to 37.6 mm overall (51.1 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "ventilation equipment with frequent bearing changes", "one-direction conveyor drives", "tiller and cultivator rotors" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 31.75 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 51.1 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Catalogue ratings belong to YELAG 207-104 as the ecc two ag execution; other order numbers of the YELAG 207-104 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-207-104?", "a": "The catalogue envelope is 31.75x72x37.6 mm with a spherical outside surface; mass 600 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 1,100 r/min." }, { "q": "What does the designation YELAG 207-104 mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -104 = 31.75 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YEL-207-104-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 207-104-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-207-104", "YELAG 207-104" ], "locale_variants": {} }, { "sku": "YEL-207-104-2F", "brand": "SKF", "manufacturer_designation": "YEL 207-104-2F", "series": "YEL2-series", "type": "insert", "d_mm": 31.75, "D_mm": 72, "B_mm": 37.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 610, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YEL 207-104-2F is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 31.75x72x37.6 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -104 = 31.75 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 31.75x72x37.6 mm (1.25x2.835x1.48 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 51.1 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 610 g. Load balance for documentation: C0 15.3 kN against C 25.5 kN gives a 0.6 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Bore-to-OD planning: OD 72 over bore 31.75 is a 2.268x step, while bore/overall-width gives 0.844; the spherical seat in the matching Y-housing must be specified to the 72 mm OD, not to a cylindrical housing bore. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 46.1 mm, d2 51.1 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Mass-to-load ratio for YEL-207-104-2F: 23.922 g of catalogue mass per rated kN of C, and 19.213 g per millimetre of bore — useful when comparing executions of the same 31.75x72 mm envelope on the drawing. Spherical-seat note in numbers: the 72 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 51.875 = 162.97 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Collar geometry for this size: over the 19 mm outer-ring width the inner ring runs to 37.6 mm overall (51.1 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "agricultural machinery PTO-driven shafts", "tiller and cultivator rotors", "ventilation equipment with frequent bearing changes" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 31.75 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 51.1 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Ordering discipline for the 31.75 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-207-104-2F?", "a": "The catalogue envelope is 31.75x72x37.6 mm with a spherical outside surface; mass 610 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 5,300 r/min." }, { "q": "What does the designation YEL 207-104-2F mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -104 = 31.75 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YELAG-207-104", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 207-104 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-207-104-2F", "YEL 207-104-2F" ], "locale_variants": {} }, { "sku": "YET-207-105", "brand": "SKF", "manufacturer_designation": "YET 207-105", "series": "YEL2-series", "type": "insert", "d_mm": 33.3375, "D_mm": 72, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 490, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YET 207-105 is a eccentric-locking-collar insert bearing with a one-side-extended inner ring, 33.3375x72x25.4 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -105 = 33.337 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 33.3375x72x25.4 mm (1.313x2.835x1 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 38.9 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 490 g. Envelope arithmetic: the radial section from 33.3375 mm bore to 72 mm OD is 19.331 mm; dividing C 25.5 kN by that section gives 1.319 kN per section millimetre, and the 25.4 mm overall width is 1.314x the section. Bore-to-OD planning: OD 72 over bore 33.3375 is a 2.16x step, while bore/overall-width gives 1.313; the spherical seat in the matching Y-housing must be specified to the 72 mm OD, not to a cylindrical housing bore. Outer-vs-overall width: the outer ring is 19 mm wide inside the 25.4 mm total, so the extended inner ring accounts for 0.252 of the overall width (6.4 mm of axial projection on the locking side). Spherical-seat note in numbers: the 72 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 52.669 = 165.465 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fatigue-limit check: Pu 0.655 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YET 207-105 — most belt-driven mounted-unit loads sit comfortably under 2.569 % of C. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Collar geometry for this size: over the 19 mm outer-ring width the inner ring runs to 25.4 mm overall (38.9 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "tiller and cultivator rotors", "one-direction conveyor drives", "agricultural machinery PTO-driven shafts" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 33.3375 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 38.9 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Catalogue ratings belong to YET 207-105 as the ecc one open execution; other order numbers of the YET 207-105 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-207-105?", "a": "The catalogue envelope is 33.3375x72x25.4 mm with a spherical outside surface; mass 490 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 5,300 r/min." }, { "q": "What does the designation YET 207-105 mean?", "a": "reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -105 = 33.337 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-207-105", "YET 207-105" ], "locale_variants": {} }, { "sku": "YET-207-106", "brand": "SKF", "manufacturer_designation": "YET 207-106", "series": "YEL2-series", "type": "insert", "d_mm": 34.925, "D_mm": 72, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 460, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YET 207-106 is a SKF insert bearing (Y-bearing) for a 34.925 mm (1.375 in) shaft: eccentric-locking-collar insert bearing with a one-side-extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YET means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on one side. inch bore code -106 decodes as 1\" +6/16, i.e. 34.925 mm; the metric coded size YET 207 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YEL2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings. Envelope 34.925x72x25.4 mm (1.375x2.835x1 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 38.9 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 460 g. Outer-vs-overall width: the outer ring is 19 mm wide inside the 25.4 mm total, so the extended inner ring accounts for 0.252 of the overall width (6.4 mm of axial projection on the locking side). Rating split for the maintenance file: dynamic 25.5 kN (L10), static 15.3 kN (s0 shock check), fatigue 0.655 kN (adjusted life) — three separate uses for YET 207-106, none interchangeable with another. Speed ceiling of 5,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Imperial procurement cross-check: 1.375 in bore, 2.835 in OD, 1 in overall width; the 460 g mass converts to 0.460 kg (16.2 oz) for the bill of materials. Grease-life arithmetic is dominated by speed: at dn approx 2.83x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Collar geometry for this size: over the 19 mm outer-ring width the inner ring runs to 25.4 mm overall (38.9 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "one-direction conveyor drives", "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes" ], "failure_modes": [ "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 38.9 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "The eccentric collar is handed to running direction; fit it wrong on the 34.925 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Ordering discipline for the 34.925 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-207-106?", "a": "Boundary dimensions: bore 34.925 mm, sphered OD 72 mm, overall width 25.4 mm (38.9 mm with the collar); weight 460 g. Loads: dynamic 25.5 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 5,300 r/min limiting value." }, { "q": "What does the designation YET 207-106 mean?", "a": "YET means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on one side. inch bore code -106 decodes as 1\" +6/16, i.e. 34.925 mm; the metric coded size YET 207 shares the same envelope but its bore is the metric value, not this one. with no -2F/-2RF suffix the order number denotes the open external execution of the YEL2 size — add external exclusion at the housing and plan relubrication intervals for dusty or wet surroundings." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YET-207", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x25.4 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 207 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YET-207-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x25.4 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YET 207/VL065 is the eccentric collar locking, one-side-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-207-106", "YET 207-106" ], "locale_variants": {} }, { "sku": "YELAG-207-106", "brand": "SKF", "manufacturer_designation": "YELAG 207-106", "series": "YEL2-series", "type": "insert", "d_mm": 34.925, "D_mm": 72, "B_mm": 37.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 540, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YELAG 207-106 is a SKF insert bearing (Y-bearing) for a 34.925 mm (1.375 in) shaft: eccentric-locking-collar insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -106 decodes as 1\" +6/16, i.e. 34.925 mm; the metric coded size YELAG 207 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution. Envelope 34.925x72x37.6 mm (1.375x2.835x1.48 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 51.1 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 1,100 r/min; mass 540 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 46.1 mm, d2 51.1 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Width accounting: B1 51.1 mm covers the bearing WITH its eccentric locking collar against 37.6 mm for the bearing itself and 19 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Speed ceiling of 1,100 r/min is the catalogue mechanical limit for THIS execution; the AG agricultural derate is deliberate, so real fan duty is planned well below it. Static-first planning: the 0.407 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 34.925 mm shaft, not the 25.5 kN L10 value. Selection figures for YELAG 207-106: C0/C is 0.6, Pu 0.655 kN is 2.569 % of the 25.5 kN dynamic rating, and the 540 g catalogue mass works out to roughly 15.462 g per millimetre of the 34.925 mm bore. Collar geometry for this size: over the 19 mm outer-ring width the inner ring runs to 37.6 mm overall (51.1 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "ventilation equipment with frequent bearing changes", "tiller and cultivator rotors", "one-direction conveyor drives" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 34.925 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 51.1 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Ordering discipline for the 34.925 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-207-106?", "a": "Boundary dimensions: bore 34.925 mm, sphered OD 72 mm, overall width 37.6 mm (51.1 mm with the collar); weight 540 g. Loads: dynamic 25.5 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 1,100 r/min limiting value." }, { "q": "What does the designation YELAG 207-106 mean?", "a": "YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -106 decodes as 1\" +6/16, i.e. 34.925 mm; the metric coded size YELAG 207 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YELAG-207", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 207 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-207-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 207-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-207-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 207-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-207-106-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 207-106-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-207-106", "YELAG 207-106" ], "locale_variants": {} }, { "sku": "YEL-207-106-2F", "brand": "SKF", "manufacturer_designation": "YEL 207-106-2F", "series": "YEL2-series", "type": "insert", "d_mm": 34.925, "D_mm": 72, "B_mm": 37.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YEL 207-106-2F is SKF's 34.925 mm-bore eccentric-locking-collar insert bearing with the inner ring extended on both sides in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 34.925x72x37.6 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the three-digit -106 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 6/16 in = 34.925 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 34.925x72x37.6 mm (1.375x2.835x1.48 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 51.1 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 550 g. Spherical-seat note in numbers: the 72 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 53.462 = 167.956 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Imperial procurement cross-check: 1.375 in bore, 2.835 in OD, 1.48 in overall width; the 550 g mass converts to 0.550 kg (19.4 oz) for the bill of materials. Width accounting: B1 51.1 mm covers the bearing WITH its eccentric locking collar against 37.6 mm for the bearing itself and 19 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 34.925x72 mm insert on its chamfer tilts the whole spherical seat. Mass-to-load ratio for YEL-207-106-2F: 21.569 g of catalogue mass per rated kN of C, and 15.748 g per millimetre of bore — useful when comparing executions of the same 34.925x72 mm envelope on the drawing. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Collar geometry for this size: over the 19 mm outer-ring width the inner ring runs to 37.6 mm overall (51.1 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes", "tiller and cultivator rotors" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 51.1 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "The eccentric collar is handed to running direction; fit it wrong on the 34.925 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Ordering discipline for the 34.925 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-207-106-2F?", "a": "YEL 207-106-2F measures 34.925 mm bore x 72 mm OD x 37.6 mm overall width (outer ring 19 mm wide), 1.375 x 2.835 x 1.48 in; mass about 550 g. SKF 17000 ratings: C 25.5 kN, C0 15.3 kN, Pu 0.655 kN, limiting speed 5,300 r/min." }, { "q": "What does the designation YEL 207-106-2F mean?", "a": "the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the three-digit -106 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 6/16 in = 34.925 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YELAG-207", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 207 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-207-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 207-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YEL-207-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 207-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YELAG-207-106", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 207-106 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-207-106-2F", "YEL 207-106-2F" ], "locale_variants": {} }, { "sku": "YET-207-107", "brand": "SKF", "manufacturer_designation": "YET 207-107", "series": "YEL2-series", "type": "insert", "d_mm": 36.512499999999996, "D_mm": 72, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YET 207-107 is SKF's 36.512499999999996 mm-bore eccentric-locking-collar insert bearing with a one-side-extended inner ring in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 36.512499999999996x72x25.4 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the three-digit -107 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 7/16 in = 36.512 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 25.4 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals. Envelope 36.512499999999996x72x25.4 mm (1.438x2.835x1 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 38.9 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 440 g. Grease-life arithmetic is dominated by speed: at dn approx 2.88x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Static-first planning: the 0.602 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 36.512499999999996 mm shaft, not the 25.5 kN L10 value. Envelope arithmetic: the radial section from 36.512499999999996 mm bore to 72 mm OD is 17.744 mm; dividing C 25.5 kN by that section gives 1.437 kN per section millimetre, and the 25.4 mm overall width is 1.431x the section. Load balance for documentation: C0 15.3 kN against C 25.5 kN gives a 0.6 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Bore-to-OD planning: OD 72 over bore 36.512499999999996 is a 1.972x step, while bore/overall-width gives 1.438; the spherical seat in the matching Y-housing must be specified to the 72 mm OD, not to a cylindrical housing bore. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Direction rule for YET-207-107: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 36.512499999999996 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "ventilation equipment with frequent bearing changes", "agricultural machinery PTO-driven shafts", "tiller and cultivator rotors" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 36.512499999999996 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 38.9 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Catalogue ratings belong to YET 207-107 as the ecc one open execution; other order numbers of the YET 207-107 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-207-107?", "a": "YET 207-107 measures 36.512499999999996 mm bore x 72 mm OD x 25.4 mm overall width (outer ring 19 mm wide), 1.438 x 2.835 x 1 in; mass about 440 g. SKF 17000 ratings: C 25.5 kN, C0 15.3 kN, Pu 0.655 kN, limiting speed 5,300 r/min." }, { "q": "What does the designation YET 207-107 mean?", "a": "the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the three-digit -107 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 7/16 in = 36.512 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 25.4 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-207-107", "YET 207-107" ], "locale_variants": {} }, { "sku": "YELAG-207-107", "brand": "SKF", "manufacturer_designation": "YELAG 207-107", "series": "YEL2-series", "type": "insert", "d_mm": 36.512499999999996, "D_mm": 72, "B_mm": 37.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YELAG 207-107 is SKF's 36.512499999999996 mm-bore eccentric-locking-collar insert bearing with the inner ring extended on both sides in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 36.512499999999996x72x37.6 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the three-digit -107 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 7/16 in = 36.512 mm (first digit whole inches, next two sixteenths of an inch). AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant. Envelope 36.512499999999996x72x37.6 mm (1.438x2.835x1.48 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 51.1 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 1,100 r/min; mass 500 g. Speed ceiling of 1,100 r/min is the catalogue mechanical limit for THIS execution; the AG agricultural derate is deliberate, so real fan duty is planned well below it. Pitch-diameter arithmetic: dm = (36.512499999999996+72)/2 = 54.256 mm; at the 1,100 r/min limiting speed the ball set runs at dn approx 0.60x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Mass-to-load ratio for YELAG-207-107: 19.608 g of catalogue mass per rated kN of C, and 13.694 g per millimetre of bore — useful when comparing executions of the same 36.512499999999996x72 mm envelope on the drawing. Static-first planning: the 0.407 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 36.512499999999996 mm shaft, not the 25.5 kN L10 value. Width accounting: B1 51.1 mm covers the bearing WITH its eccentric locking collar against 37.6 mm for the bearing itself and 19 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Direction rule for YELAG-207-107: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 36.512499999999996 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "one-direction conveyor drives", "tiller and cultivator rotors", "agricultural machinery PTO-driven shafts" ], "failure_modes": [ "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Overall width 51.1 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "The eccentric collar is handed to running direction; fit it wrong on the 36.512499999999996 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The 25.5/15.3 kN figures belong specifically to YELAG 207-107; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-207-107?", "a": "YELAG 207-107 measures 36.512499999999996 mm bore x 72 mm OD x 37.6 mm overall width (outer ring 19 mm wide), 1.438 x 2.835 x 1.48 in; mass about 500 g. SKF 17000 ratings: C 25.5 kN, C0 15.3 kN, Pu 0.655 kN, limiting speed 1,100 r/min." }, { "q": "What does the designation YELAG 207-107 mean?", "a": "the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the three-digit -107 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 7/16 in = 36.512 mm (first digit whole inches, next two sixteenths of an inch). AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YEL-207-107-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 36.512499999999996x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 207-107-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-207-107", "YELAG 207-107" ], "locale_variants": {} }, { "sku": "YEL-207-107-2F", "brand": "SKF", "manufacturer_designation": "YEL 207-107-2F", "series": "YEL2-series", "type": "insert", "d_mm": 36.512499999999996, "D_mm": 72, "B_mm": 37.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 510, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YEL 207-107-2F is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 36.512499999999996x72x37.6 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -107 = 36.512 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 36.512499999999996x72x37.6 mm (1.438x2.835x1.48 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 51.1 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 510 g. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 36.512499999999996x72 mm insert on its chamfer tilts the whole spherical seat. At the printed limiting speed of 5,300 r/min the mean diameter dm = 54.256 mm implies dn about 2.88x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Imperial procurement cross-check: 1.438 in bore, 2.835 in OD, 1.48 in overall width; the 510 g mass converts to 0.510 kg (18.0 oz) for the bill of materials. Bore-to-OD planning: OD 72 over bore 36.512499999999996 is a 1.972x step, while bore/overall-width gives 0.971; the spherical seat in the matching Y-housing must be specified to the 72 mm OD, not to a cylindrical housing bore. Capacity density: 25.5 kN from 0.510 kg of bearing steel is about 50 kN per kilogram, and per width millimetre the 37.6 mm unit carries 0.678 kN of dynamic capacity. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Direction rule for YEL-207-107-2F: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 36.512499999999996 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "tiller and cultivator rotors", "one-direction conveyor drives", "agricultural machinery PTO-driven shafts" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 36.512499999999996 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 51.1 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Catalogue ratings belong to YEL 207-107-2F as the ecc two f execution; other order numbers of the YEL 207-107 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-207-107-2F?", "a": "The catalogue envelope is 36.512499999999996x72x37.6 mm with a spherical outside surface; mass 510 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 5,300 r/min." }, { "q": "What does the designation YEL 207-107-2F mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -107 = 36.512 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YELAG-207-107", "equiv_brand": "SKF", "level": "full", "note": "Same 36.512499999999996x72x37.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 207-107 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-207-107-2F", "YEL 207-107-2F" ], "locale_variants": {} }, { "sku": "YET-208-108", "brand": "SKF", "manufacturer_designation": "YET 208-108", "series": "YEL2-series", "type": "insert", "d_mm": 38.099999999999994, "D_mm": 80, "B_mm": 29.7, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 640, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YET 208-108 is a eccentric-locking-collar insert bearing with a one-side-extended inner ring, 38.099999999999994x80x29.7 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -108 = 38.1 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 38.099999999999994x80x29.7 mm (1.5x3.15x1.169 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. Mounted width B1 43.2 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 4,800 r/min; mass 640 g. Selection figures for YET 208-108: C0/C is 0.619, Pu 0.8 kN is 2.606 % of the 30.7 kN dynamic rating, and the 640 g catalogue mass works out to roughly 16.798 g per millimetre of the 38.099999999999994 mm bore. Load balance for documentation: C0 19 kN against C 30.7 kN gives a 0.619 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Imperial procurement cross-check: 1.5 in bore, 3.15 in OD, 1.169 in overall width; the 640 g mass converts to 0.640 kg (22.6 oz) for the bill of materials. Static-first planning: the 0.64 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 38.099999999999994 mm shaft, not the 30.7 kN L10 value. Grease-life arithmetic is dominated by speed: at dn approx 2.83x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Direction rule for YET-208-108: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 38.099999999999994 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "one-direction conveyor drives", "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes" ], "failure_modes": [ "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 38.099999999999994 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 43.2 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Ordering discipline for the 38.099999999999994 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-208-108?", "a": "The catalogue envelope is 38.099999999999994x80x29.7 mm with a spherical outside surface; mass 640 g. Ratings C 30.7/19 kN, Pu 0.8 kN, limiting speed 4,800 r/min." }, { "q": "What does the designation YET 208-108 mean?", "a": "reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -108 = 38.1 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-208-108", "YET 208-108" ], "locale_variants": {} }, { "sku": "YELAG-208-108", "brand": "SKF", "manufacturer_designation": "YELAG 208-108", "series": "YEL2-series", "type": "insert", "d_mm": 38.099999999999994, "D_mm": 80, "B_mm": 42.8, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 950, "max_rpm": 950, "weight_g": 740, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YELAG 208-108 is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 38.099999999999994x80x42.8 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -108 = 38.1 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 38.099999999999994x80x42.8 mm (1.5x3.15x1.685 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. Mounted width B1 56.3 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 950 r/min; mass 740 g. Envelope arithmetic: the radial section from 38.099999999999994 mm bore to 80 mm OD is 20.95 mm; dividing C 30.7 kN by that section gives 1.465 kN per section millimetre, and the 42.8 mm overall width is 2.043x the section. Bore-to-OD planning: OD 80 over bore 38.099999999999994 is a 2.1x step, while bore/overall-width gives 0.89; the spherical seat in the matching Y-housing must be specified to the 80 mm OD, not to a cylindrical housing bore. Outer-vs-overall width: the outer ring is 21 mm wide inside the 42.8 mm total, so the extended inner ring accounts for 0.509 of the overall width (10.9 mm of axial projection per side). Spherical-seat note in numbers: the 80 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 59.05 = 185.511 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fatigue-limit check: Pu 0.8 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YELAG 208-108 — most belt-driven mounted-unit loads sit comfortably under 2.606 % of C. Collar geometry for this size: over the 21 mm outer-ring width the inner ring runs to 42.8 mm overall (56.3 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "tiller and cultivator rotors", "one-direction conveyor drives", "agricultural machinery PTO-driven shafts" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 56.3 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "The eccentric collar is handed to running direction; fit it wrong on the 38.099999999999994 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Ordering discipline for the 38.099999999999994 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-208-108?", "a": "The catalogue envelope is 38.099999999999994x80x42.8 mm with a spherical outside surface; mass 740 g. Ratings C 30.7/19 kN, Pu 0.8 kN, limiting speed 950 r/min." }, { "q": "What does the designation YELAG 208-108 mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -108 = 38.1 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YEL-208-108-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 208-108-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSPAG-208-108", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 208-108 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSP-208-108-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 208-108 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-208-108", "YELAG 208-108" ], "locale_variants": {} }, { "sku": "YEL-208-108-2F", "brand": "SKF", "manufacturer_designation": "YEL 208-108-2F", "series": "YEL2-series", "type": "insert", "d_mm": 38.099999999999994, "D_mm": 80, "B_mm": 42.8, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 760, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YEL 208-108-2F is SKF's 38.099999999999994 mm-bore eccentric-locking-collar insert bearing with the inner ring extended on both sides in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 38.099999999999994x80x42.8 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the three-digit -108 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 8/16 in = 38.1 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 38.099999999999994x80x42.8 mm (1.5x3.15x1.685 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. Mounted width B1 56.3 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 4,800 r/min; mass 760 g. Spherical-seat note in numbers: the 80 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 59.05 = 185.511 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 51.8 mm, d2 56.5 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Bore-to-OD planning: OD 80 over bore 38.099999999999994 is a 2.1x step, while bore/overall-width gives 0.89; the spherical seat in the matching Y-housing must be specified to the 80 mm OD, not to a cylindrical housing bore. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 38.099999999999994x80 mm insert on its chamfer tilts the whole spherical seat. Speed ceiling of 4,800 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Direction rule for YEL-208-108-2F: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 38.099999999999994 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "agricultural machinery PTO-driven shafts", "one-direction conveyor drives", "ventilation equipment with frequent bearing changes" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 56.3 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "The eccentric collar is handed to running direction; fit it wrong on the 38.099999999999994 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Ordering discipline for the 38.099999999999994 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-208-108-2F?", "a": "YEL 208-108-2F measures 38.099999999999994 mm bore x 80 mm OD x 42.8 mm overall width (outer ring 21 mm wide), 1.5 x 3.15 x 1.685 in; mass about 760 g. SKF 17000 ratings: C 30.7 kN, C0 19 kN, Pu 0.8 kN, limiting speed 4,800 r/min." }, { "q": "What does the designation YEL 208-108-2F mean?", "a": "the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the three-digit -108 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 8/16 in = 38.1 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YELAG-208-108", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 208-108 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSPAG-208-108", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 208-108 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSP-208-108-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 208-108 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-208-108-2F", "YEL 208-108-2F" ], "locale_variants": {} }, { "sku": "YET-209-111", "brand": "SKF", "manufacturer_designation": "YET 209-111", "series": "YEL2-series", "type": "insert", "d_mm": 42.8625, "D_mm": 85, "B_mm": 30.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 730, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YET 209-111 is SKF's 42.8625 mm-bore eccentric-locking-collar insert bearing with a one-side-extended inner ring in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 42.8625x85x30.2 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the three-digit -111 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 11/16 in = 42.862 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 30.2 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals. Envelope 42.8625x85x30.2 mm (1.688x3.346x1.189 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. Mounted width B1 43.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 730 g. The s1 32.7 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Width accounting: B1 43.7 mm covers the bearing WITH its eccentric locking collar against 30.2 mm for the bearing itself and 22 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Bore-to-OD planning: OD 85 over bore 42.8625 is a 1.983x step, while bore/overall-width gives 1.419; the spherical seat in the matching Y-housing must be specified to the 85 mm OD, not to a cylindrical housing bore. Rating split for the maintenance file: dynamic 33.2 kN (L10), static 21.6 kN (s0 shock check), fatigue 0.915 kN (adjusted life) — three separate uses for YET 209-111, none interchangeable with another. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 42.8625x85 mm insert on its chamfer tilts the whole spherical seat. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Direction rule for YET-209-111: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 42.8625 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes", "tiller and cultivator rotors" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 42.8625 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 43.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Ordering discipline for the 42.8625 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-209-111?", "a": "YET 209-111 measures 42.8625 mm bore x 85 mm OD x 30.2 mm overall width (outer ring 22 mm wide), 1.688 x 3.346 x 1.189 in; mass about 730 g. SKF 17000 ratings: C 33.2 kN, C0 21.6 kN, Pu 0.915 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YET 209-111 mean?", "a": "the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the three-digit -111 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 11/16 in = 42.862 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 30.2 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-209-111", "YET 209-111" ], "locale_variants": {} }, { "sku": "YELAG-209-111", "brand": "SKF", "manufacturer_designation": "YELAG 209-111", "series": "YEL2-series", "type": "insert", "d_mm": 42.8625, "D_mm": 85, "B_mm": 42.8, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 850, "max_rpm": 850, "weight_g": 840, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YELAG 209-111 is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 42.8625x85x42.8 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -111 = 42.862 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 42.8625x85x42.8 mm (1.688x3.346x1.685 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. Mounted width B1 56.3 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 850 r/min; mass 840 g. Mass-to-load ratio for YELAG-209-111: 25.301 g of catalogue mass per rated kN of C, and 19.598 g per millimetre of bore — useful when comparing executions of the same 42.8625x85 mm envelope on the drawing. Grease-life arithmetic is dominated by speed: at dn approx 0.54x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the AG variant caps speed so aggressively, and high-temperature mounts shorten both even when load is light. Load balance for documentation: C0 21.6 kN against C 33.2 kN gives a 0.651 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 42.8625x85 mm insert on its chamfer tilts the whole spherical seat. Capacity density: 33.2 kN from 0.840 kg of bearing steel is about 39.524 kN per kilogram, and per width millimetre the 42.8 mm unit carries 0.776 kN of dynamic capacity. Direction rule for YELAG-209-111: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 42.8625 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "tiller and cultivator rotors", "one-direction conveyor drives", "agricultural machinery PTO-driven shafts" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 56.3 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "The eccentric collar is handed to running direction; fit it wrong on the 42.8625 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Ordering discipline for the 42.8625 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-209-111?", "a": "The catalogue envelope is 42.8625x85x42.8 mm with a spherical outside surface; mass 840 g. Ratings C 33.2/21.6 kN, Pu 0.915 kN, limiting speed 850 r/min." }, { "q": "What does the designation YELAG 209-111 mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -111 = 42.862 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YEL-209-111-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 42.8625x85x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 209-111-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-209-111", "YELAG 209-111" ], "locale_variants": {} }, { "sku": "YEL-209-111-2F", "brand": "SKF", "manufacturer_designation": "YEL 209-111-2F", "series": "YEL2-series", "type": "insert", "d_mm": 42.8625, "D_mm": 85, "B_mm": 42.8, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 860, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YEL 209-111-2F is SKF's 42.8625 mm-bore eccentric-locking-collar insert bearing with the inner ring extended on both sides in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 42.8625x85x42.8 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the three-digit -111 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 11/16 in = 42.862 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 42.8625x85x42.8 mm (1.688x3.346x1.685 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. Mounted width B1 56.3 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 860 g. Capacity density: 33.2 kN from 0.860 kg of bearing steel is about 38.605 kN per kilogram, and per width millimetre the 42.8 mm unit carries 0.776 kN of dynamic capacity. Bore-to-OD planning: OD 85 over bore 42.8625 is a 1.983x step, while bore/overall-width gives 1.001; the spherical seat in the matching Y-housing must be specified to the 85 mm OD, not to a cylindrical housing bore. Envelope arithmetic: the radial section from 42.8625 mm bore to 85 mm OD is 21.069 mm; dividing C 33.2 kN by that section gives 1.576 kN per section millimetre, and the 42.8 mm overall width is 2.031x the section. Spherical-seat note in numbers: the 85 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 63.931 = 200.845 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Outer-vs-overall width: the outer ring is 22 mm wide inside the 42.8 mm total, so the extended inner ring accounts for 0.486 of the overall width (10.4 mm of axial projection per side). Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Direction rule for YEL-209-111-2F: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 42.8625 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "one-direction conveyor drives", "tiller and cultivator rotors", "agricultural machinery PTO-driven shafts" ], "failure_modes": [ "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The eccentric collar is handed to running direction; fit it wrong on the 42.8625 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 56.3 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Catalogue ratings belong to YEL 209-111-2F as the ecc two f execution; other order numbers of the YEL 209-111 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-209-111-2F?", "a": "YEL 209-111-2F measures 42.8625 mm bore x 85 mm OD x 42.8 mm overall width (outer ring 22 mm wide), 1.688 x 3.346 x 1.685 in; mass about 860 g. SKF 17000 ratings: C 33.2 kN, C0 21.6 kN, Pu 0.915 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YEL 209-111-2F mean?", "a": "the YEL prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended both sides. the three-digit -111 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 11/16 in = 42.862 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YELAG-209-111", "equiv_brand": "SKF", "level": "full", "note": "Same 42.8625x85x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 209-111 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-209-111-2F", "YEL 209-111-2F" ], "locale_variants": {} }, { "sku": "YET-209-112", "brand": "SKF", "manufacturer_designation": "YET 209-112", "series": "YEL2-series", "type": "insert", "d_mm": 44.449999999999996, "D_mm": 85, "B_mm": 30.2, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 690, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YET 209-112 is SKF's 44.449999999999996 mm-bore eccentric-locking-collar insert bearing with a one-side-extended inner ring in the YEL2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 44.449999999999996x85x30.2 mm. The deep-groove ball set is built into an extended inner ring carrying a separate eccentric locking collar; turning the collar against its eccentric seat pinches the shaft, and the sphered outer ring self-aligns in the housing. the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the three-digit -112 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 12/16 in = 44.45 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 30.2 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals. Envelope 44.449999999999996x85x30.2 mm (1.75x3.346x1.189 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. Mounted width B1 43.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 690 g. Pitch-diameter arithmetic: dm = (44.449999999999996+85)/2 = 64.725 mm; at the 4,300 r/min limiting speed the ball set runs at dn approx 2.78x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. The s1 32.7 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Rating split for the maintenance file: dynamic 33.2 kN (L10), static 21.6 kN (s0 shock check), fatigue 0.915 kN (adjusted life) — three separate uses for YET 209-112, none interchangeable with another. Envelope arithmetic: the radial section from 44.449999999999996 mm bore to 85 mm OD is 20.275 mm; dividing C 33.2 kN by that section gives 1.637 kN per section millimetre, and the 30.2 mm overall width is 1.49x the section. Mass-to-load ratio for YET-209-112: 20.783 g of catalogue mass per rated kN of C, and 15.523 g per millimetre of bore — useful when comparing executions of the same 44.449999999999996x85 mm envelope on the drawing. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Collar geometry for this size: over the 22 mm outer-ring width the inner ring runs to 30.2 mm overall (43.7 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "tiller and cultivator rotors", "agricultural machinery PTO-driven shafts", "one-direction conveyor drives" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 43.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "The eccentric collar is handed to running direction; fit it wrong on the 44.449999999999996 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Ordering discipline for the 44.449999999999996 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-209-112?", "a": "YET 209-112 measures 44.449999999999996 mm bore x 85 mm OD x 30.2 mm overall width (outer ring 22 mm wide), 1.75 x 3.346 x 1.189 in; mass about 690 g. SKF 17000 ratings: C 33.2 kN, C0 21.6 kN, Pu 0.915 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YET 209-112 mean?", "a": "the YET prefix identifies the eccentric-locking-collar design: a separate eccentric collar turns against a matching eccentric on the extended inner ring to pinch the shaft, extended one side. the three-digit -112 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 12/16 in = 44.45 mm (first digit whole inches, next two sixteenths of an inch). this suffix-free execution is listed without the sealed external design: the 30.2 mm width is the one-side-extended inner ring alone, so protection depends on the housing seals and the relubrication routine rather than bearing-mounted contact seals." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-209-112", "YET 209-112" ], "locale_variants": {} }, { "sku": "YELAG-209-112", "brand": "SKF", "manufacturer_designation": "YELAG 209-112", "series": "YEL2-series", "type": "insert", "d_mm": 44.449999999999996, "D_mm": 85, "B_mm": 42.8, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 850, "max_rpm": 850, "weight_g": 800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YELAG 209-112 is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 44.449999999999996x85x42.8 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -112 = 44.45 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 44.449999999999996x85x42.8 mm (1.75x3.346x1.685 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. Mounted width B1 56.3 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 850 r/min; mass 800 g. Imperial procurement cross-check: 1.75 in bore, 3.346 in OD, 1.685 in overall width; the 800 g mass converts to 0.800 kg (28.2 oz) for the bill of materials. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 44.449999999999996x85 mm insert on its chamfer tilts the whole spherical seat. Fatigue-limit check: Pu 0.915 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YELAG 209-112 — most belt-driven mounted-unit loads sit comfortably under 2.756 % of C. Static-first planning: the 0.505 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 44.449999999999996 mm shaft, not the 33.2 kN L10 value. Grease-life arithmetic is dominated by speed: at dn approx 0.55x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the AG variant caps speed so aggressively, and high-temperature mounts shorten both even when load is light. Collar geometry for this size: over the 22 mm outer-ring width the inner ring runs to 42.8 mm overall (56.3 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "agricultural machinery PTO-driven shafts", "tiller and cultivator rotors", "ventilation equipment with frequent bearing changes" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Overall width 56.3 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "The eccentric collar is handed to running direction; fit it wrong on the 44.449999999999996 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The 33.2/21.6 kN figures belong specifically to YELAG 209-112; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-209-112?", "a": "The catalogue envelope is 44.449999999999996x85x42.8 mm with a spherical outside surface; mass 800 g. Ratings C 33.2/21.6 kN, Pu 0.915 kN, limiting speed 850 r/min." }, { "q": "What does the designation YELAG 209-112 mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -112 = 44.45 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." } ], "cross_ref": [ { "equiv_sku": "YEL-209-112-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 44.449999999999996x85x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 209-112-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-209-112", "YELAG 209-112" ], "locale_variants": {} }, { "sku": "YEL-209-112-2F", "brand": "SKF", "manufacturer_designation": "YEL 209-112-2F", "series": "YEL2-series", "type": "insert", "d_mm": 44.449999999999996, "D_mm": 85, "B_mm": 42.8, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 810, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YEL 209-112-2F is a eccentric-locking-collar insert bearing with the inner ring extended on both sides, 44.449999999999996x85x42.8 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -112 = 44.45 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 44.449999999999996x85x42.8 mm (1.75x3.346x1.685 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. Mounted width B1 56.3 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 810 g. Rating split for the maintenance file: dynamic 33.2 kN (L10), static 21.6 kN (s0 shock check), fatigue 0.915 kN (adjusted life) — three separate uses for YEL 209-112-2F, none interchangeable with another. At the printed limiting speed of 4,300 r/min the mean diameter dm = 64.725 mm implies dn about 2.78x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. The s1 34.9 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Pitch-diameter arithmetic: dm = (44.449999999999996+85)/2 = 64.725 mm; at the 4,300 r/min limiting speed the ball set runs at dn approx 2.78x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Width accounting: B1 56.3 mm covers the bearing WITH its eccentric locking collar against 42.8 mm for the bearing itself and 22 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Collar geometry for this size: over the 22 mm outer-ring width the inner ring runs to 42.8 mm overall (56.3 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "ventilation equipment with frequent bearing changes", "one-direction conveyor drives", "tiller and cultivator rotors" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 44.449999999999996 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 56.3 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Ordering discipline for the 44.449999999999996 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-209-112-2F?", "a": "The catalogue envelope is 44.449999999999996x85x42.8 mm with a spherical outside surface; mass 810 g. Ratings C 33.2/21.6 kN, Pu 0.915 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YEL 209-112-2F mean?", "a": "reading YEL: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended symmetrically both sides. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -112 = 44.45 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YELAG-209-112", "equiv_brand": "SKF", "level": "full", "note": "Same 44.449999999999996x85x42.8 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 209-112 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-209-112-2F", "YEL 209-112-2F" ], "locale_variants": {} }, { "sku": "YELAG-210-115", "brand": "SKF", "manufacturer_designation": "YELAG 210-115", "series": "YEL2-series", "type": "insert", "d_mm": 49.2125, "D_mm": 90, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 800, "max_rpm": 800, "weight_g": 940, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YELAG 210-115 is a SKF insert bearing (Y-bearing) for a 49.2125 mm (1.938 in) shaft: eccentric-locking-collar insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 90 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -115 decodes as 1\" +15/16, i.e. 49.212 mm; the metric coded size YELAG 210 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution. Envelope 49.2125x90x49.2 mm (1.938x3.543x1.937 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. Mounted width B1 62.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 800 r/min; mass 940 g. Bore-to-OD planning: OD 90 over bore 49.2125 is a 1.829x step, while bore/overall-width gives 1; the spherical seat in the matching Y-housing must be specified to the 90 mm OD, not to a cylindrical housing bore. Speed ceiling of 800 r/min is the catalogue mechanical limit for THIS execution; the AG agricultural derate is deliberate, so real fan duty is planned well below it. Pitch-diameter arithmetic: dm = (49.2125+90)/2 = 69.606 mm; at the 800 r/min limiting speed the ball set runs at dn approx 0.56x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Fatigue-limit check: Pu 0.98 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YELAG 210-115 — most belt-driven mounted-unit loads sit comfortably under 2.792 % of C. Mass-to-load ratio for YELAG-210-115: 26.781 g of catalogue mass per rated kN of C, and 19.101 g per millimetre of bore — useful when comparing executions of the same 49.2125x90 mm envelope on the drawing. Direction rule for YELAG-210-115: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 49.2125 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "tiller and cultivator rotors", "ventilation equipment with frequent bearing changes", "one-direction conveyor drives" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Overall width 62.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 49.2125 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "The 35.1/23.2 kN figures belong specifically to YELAG 210-115; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YELAG-210-115?", "a": "Boundary dimensions: bore 49.2125 mm, sphered OD 90 mm, overall width 49.2 mm (62.7 mm with the collar); weight 940 g. Loads: dynamic 35.1 kN, static 23.2 kN, fatigue 0.98 kN; the only published speed is the 800 r/min limiting value." }, { "q": "What does the designation YELAG 210-115 mean?", "a": "YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -115 decodes as 1\" +15/16, i.e. 49.212 mm; the metric coded size YELAG 210 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YEL-210-115-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 210-115-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YELAG-210-115", "YELAG 210-115" ], "locale_variants": {} }, { "sku": "YEL-210-115-2F", "brand": "SKF", "manufacturer_designation": "YEL 210-115-2F", "series": "YEL2-series", "type": "insert", "d_mm": 49.2125, "D_mm": 90, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YEL 210-115-2F is a SKF insert bearing (Y-bearing) for a 49.2125 mm (1.938 in) shaft: eccentric-locking-collar insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 90 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -115 decodes as 1\" +15/16, i.e. 49.212 mm; the metric coded size YEL 210 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 49.2125x90x49.2 mm (1.938x3.543x1.937 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. Mounted width B1 62.7 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 4,000 r/min; mass 950 g. Pitch-diameter arithmetic: dm = (49.2125+90)/2 = 69.606 mm; at the 4,000 r/min limiting speed the ball set runs at dn approx 2.78x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. The s1 38.1 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Fatigue-limit check: Pu 0.98 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YEL 210-115-2F — most belt-driven mounted-unit loads sit comfortably under 2.792 % of C. Envelope arithmetic: the radial section from 49.2125 mm bore to 90 mm OD is 20.394 mm; dividing C 35.1 kN by that section gives 1.721 kN per section millimetre, and the 49.2 mm overall width is 2.413x the section. Outer-vs-overall width: the outer ring is 22 mm wide inside the 49.2 mm total, so the extended inner ring accounts for 0.553 of the overall width (13.6 mm of axial projection per side). Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Collar geometry for this size: over the 22 mm outer-ring width the inner ring runs to 49.2 mm overall (62.7 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "tiller and cultivator rotors", "agricultural machinery PTO-driven shafts", "one-direction conveyor drives" ], "failure_modes": [ "collar set screw not locked into its recess: the collar unwinds and the bearing walks off its seat", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Overall width 62.7 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 49.2125 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "The 35.1/23.2 kN figures belong specifically to YEL 210-115-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-210-115-2F?", "a": "Boundary dimensions: bore 49.2125 mm, sphered OD 90 mm, overall width 49.2 mm (62.7 mm with the collar); weight 950 g. Loads: dynamic 35.1 kN, static 23.2 kN, fatigue 0.98 kN; the only published speed is the 4,000 r/min limiting value." }, { "q": "What does the designation YEL 210-115-2F mean?", "a": "YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -115 decodes as 1\" +15/16, i.e. 49.212 mm; the metric coded size YEL 210 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YELAG-210-115", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x49.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 210-115 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-210-115-2F", "YEL 210-115-2F" ], "locale_variants": {} }, { "sku": "YEL-211-200-2F", "brand": "SKF", "manufacturer_designation": "YEL 211-200-2F", "series": "YEL2-series", "type": "insert", "d_mm": 50.8, "D_mm": 100, "B_mm": 55.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 1500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YEL 211-200-2F is a SKF insert bearing (Y-bearing) for a 50.8 mm (2 in) shaft: eccentric-locking-collar insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 100 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -200 decodes as 2\", i.e. 50.8 mm; the metric coded size YEL 211 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 50.8x100x55.6 mm (2x3.937x2.189 in), outer ring 25 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. Mounted width B1 71.4 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 3,600 r/min; mass 1500 g. Static-first planning: the 0.522 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 50.8 mm shaft, not the 43.6 kN L10 value. The s1 43.6 mm dimension is printed for the locking zone — the set-screw/collar seating reference — and it is verified at mounting, not recoverable from d/D/B alone. Selection figures for YEL 211-200-2F: C0/C is 0.665, Pu 1.25 kN is 2.867 % of the 43.6 kN dynamic rating, and the 1500 g catalogue mass works out to roughly 29.528 g per millimetre of the 50.8 mm bore. Envelope arithmetic: the radial section from 50.8 mm bore to 100 mm OD is 24.6 mm; dividing C 43.6 kN by that section gives 1.772 kN per section millimetre, and the 55.6 mm overall width is 2.26x the section. Bore-to-OD planning: OD 100 over bore 50.8 is a 1.969x step, while bore/overall-width gives 0.914; the spherical seat in the matching Y-housing must be specified to the 100 mm OD, not to a cylindrical housing bore. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Collar geometry for this size: over the 25 mm outer-ring width the inner ring runs to 55.6 mm overall (71.4 mm including the eccentric collar width), giving the collar its eccentric seating face clear of the seal.", "applications": [ "agricultural machinery PTO-driven shafts", "ventilation equipment with frequent bearing changes", "tiller and cultivator rotors" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "Overall width 71.4 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "The eccentric collar is handed to running direction; fit it wrong on the 50.8 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Ordering discipline for the 50.8 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-211-200-2F?", "a": "Boundary dimensions: bore 50.8 mm, sphered OD 100 mm, overall width 55.6 mm (71.4 mm with the collar); weight 1500 g. Loads: dynamic 43.6 kN, static 29 kN, fatigue 1.25 kN; the only published speed is the 3,600 r/min limiting value." }, { "q": "What does the designation YEL 211-200-2F mean?", "a": "YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -200 decodes as 2\", i.e. 50.8 mm; the metric coded size YEL 211 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YAR-211-200-2RF", "equiv_brand": "SKF", "level": "full", "note": "Same 50.8x100x55.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 211-200-2RF is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YAR-211-200-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 50.8x100x55.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 211-200-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-211-200-2F", "YEL 211-200-2F" ], "locale_variants": {} }, { "sku": "YEL-211-203-2F", "brand": "SKF", "manufacturer_designation": "YEL 211-203-2F", "series": "YEL2-series", "type": "insert", "d_mm": 55.5625, "D_mm": 100, "B_mm": 55.6, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 1250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YEL 211-203-2F is a SKF insert bearing (Y-bearing) for a 55.5625 mm (2.188 in) shaft: eccentric-locking-collar insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 100 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -203 decodes as 2\" +3/16, i.e. 55.563 mm; the metric coded size YEL 211 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 55.5625x100x55.6 mm (2.188x3.937x2.189 in), outer ring 25 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. Mounted width B1 71.4 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 3,600 r/min; mass 1250 g. Spherical-seat note in numbers: the 100 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 77.781 = 244.356 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Outer-vs-overall width: the outer ring is 25 mm wide inside the 55.6 mm total, so the extended inner ring accounts for 0.55 of the overall width (15.3 mm of axial projection per side). Imperial procurement cross-check: 2.188 in bore, 3.937 in OD, 2.189 in overall width; the 1250 g mass converts to 1.250 kg (44.1 oz) for the bill of materials. Pitch-diameter arithmetic: dm = (55.5625+100)/2 = 77.781 mm; at the 3,600 r/min limiting speed the ball set runs at dn approx 2.80x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. At the printed limiting speed of 3,600 r/min the mean diameter dm = 77.781 mm implies dn about 2.80x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Direction rule for YEL-211-203-2F: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 55.5625 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "heavy agricultural and harvesting equipment", "one-direction bulk conveyor shafts", "forestry and chipper drives" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 55.5625 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 71.4 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Ordering discipline for the 55.5625 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-211-203-2F?", "a": "Boundary dimensions: bore 55.5625 mm, sphered OD 100 mm, overall width 55.6 mm (71.4 mm with the collar); weight 1250 g. Loads: dynamic 43.6 kN, static 29 kN, fatigue 1.25 kN; the only published speed is the 3,600 r/min limiting value." }, { "q": "What does the designation YEL 211-203-2F mean?", "a": "YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -203 decodes as 2\" +3/16, i.e. 55.563 mm; the metric coded size YEL 211 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." }, { "q": "How does the eccentric locking collar work?", "a": "The collar has an eccentric bore matching an eccentric on the inner ring extension. After sliding it on, turn it in the shaft's running direction until it grips, then tighten the collar's own set screw into its recess. Rotation then self-tightens rather than loosens the lock." } ], "cross_ref": [ { "equiv_sku": "YAR-211-203-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 55.5625x100x55.6 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YAR 211-203-2F is the grub-screw locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-211-203-2F", "YEL 211-203-2F" ], "locale_variants": {} }, { "sku": "YET-212-207", "brand": "SKF", "manufacturer_designation": "YET 212-207", "series": "YEL2-series", "type": "insert", "d_mm": 61.912499999999994, "D_mm": 110, "B_mm": 36.7, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 36, "fatigue_load_limit_kN": 1.53, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YET 212-207 is a eccentric-locking-collar insert bearing with a one-side-extended inner ring, 61.912499999999994x110x36.7 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction pairs capped deep-groove geometry with a one-piece eccentric locking collar and a convex outer ring — quick to mount on plain commercial shafts and tolerant of initial static misalignment. reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -207 = 61.912 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units. Envelope 61.912499999999994x110x36.7 mm (2.438x4.331x1.445 in), outer ring 26 mm wide, C 52.7 kN, C0 36 kN, Pu 1.53 kN. Mounted width B1 52.6 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 3,400 r/min; mass 1250 g. Static-first planning: the 0.981 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 61.912499999999994 mm shaft, not the 52.7 kN L10 value. At the printed limiting speed of 3,400 r/min the mean diameter dm = 85.956 mm implies dn about 2.92x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Mass-to-load ratio for YET-212-207: 23.719 g of catalogue mass per rated kN of C, and 20.19 g per millimetre of bore — useful when comparing executions of the same 61.912499999999994x110 mm envelope on the drawing. Width accounting: B1 52.6 mm covers the bearing WITH its eccentric locking collar against 36.7 mm for the bearing itself and 26 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Load balance for documentation: C0 36 kN against C 52.7 kN gives a 0.683 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. One-side collar note: the eccentric collar mounts on the extended side only and must turn in the shaft rotation direction to self-tighten; on reversing drives this design can loosen by design intent — choose grub-screw or ConCentra locking for true bidirectional shafts. Direction rule for YET-212-207: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 61.912499999999994 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "heavy agricultural and harvesting equipment", "forestry and chipper drives", "one-direction bulk conveyor shafts" ], "failure_modes": [ "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "eccentric collar mounted against rotation direction works loose and spins, fretting the shaft", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 61.912499999999994 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "Overall width 52.6 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YET collar.", "Ordering discipline for the 61.912499999999994 mm size: the chapter lists several executions side by side (YEL2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YET-212-207?", "a": "The catalogue envelope is 61.912499999999994x110x36.7 mm with a spherical outside surface; mass 1250 g. Ratings C 52.7/36 kN, Pu 1.53 kN, limiting speed 3,400 r/min." }, { "q": "What does the designation YET 212-207 mean?", "a": "reading YET: an eccentric locking collar does the shaft clamping (popular where shaft tolerance and quick removal matter), inner ring extended on one side. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -207 = 61.912 mm, which is why this row sits beside, not on, the metric bore size. the bare designation means no factory seal package: unlike the -2F executions this bearing relies on enclosure by the Y-housing and its own re-greasing path, which is why it is normally specified inside well-sealed plummer and flange units." }, { "q": "Why is the collar sometimes wider than the bearing (B1)?", "a": "The B1 dimension includes the eccentric collar's axial width, so the housing needs that extra space beside the bearing. Draw housings to B1, not B, when replacing a grub-screw unit with a collar unit." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." } ], "cross_ref": [ { "equiv_sku": "YET", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YET-212-207", "YET 212-207" ], "locale_variants": {} }, { "sku": "YEL-212-207-2F", "brand": "SKF", "manufacturer_designation": "YEL 212-207-2F", "series": "YEL2-series", "type": "insert", "d_mm": 61.912499999999994, "D_mm": 110, "B_mm": 61.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 36, "fatigue_load_limit_kN": 1.53, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YEL2 series order number YEL 212-207-2F is a SKF insert bearing (Y-bearing) for a 61.912499999999994 mm (2.438 in) shaft: eccentric-locking-collar insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 110 mm. Inside sits a sealed ball insert with an eccentric collar on the extended ring: collar bite locks the shaft, the contact seals retain the life grease, and the spherical OD floats in the Y-housing. YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -207 decodes as 2\" +7/16, i.e. 61.912 mm; the metric coded size YEL 212 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 61.912499999999994x110x61.9 mm (2.438x4.331x2.437 in), outer ring 26 mm wide, C 52.7 kN, C0 36 kN, Pu 1.53 kN. Mounted width B1 77.8 mm includes the eccentric collar. The catalogue publishes a single speed ceiling, the limiting speed: 3,400 r/min; mass 1600 g. Fatigue-limit check: Pu 1.53 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YEL 212-207-2F — most belt-driven mounted-unit loads sit comfortably under 2.903 % of C. Spherical-seat note in numbers: the 110 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 85.956 = 270.039 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Bore-to-OD planning: OD 110 over bore 61.912499999999994 is a 1.777x step, while bore/overall-width gives 1; the spherical seat in the matching Y-housing must be specified to the 110 mm OD, not to a cylindrical housing bore. Imperial procurement cross-check: 2.438 in bore, 4.331 in OD, 2.437 in overall width; the 1600 g mass converts to 1.600 kg (56.4 oz) for the bill of materials. Mass-to-load ratio for YEL-212-207-2F: 30.361 g of catalogue mass per rated kN of C, and 25.843 g per millimetre of bore — useful when comparing executions of the same 61.912499999999994x110 mm envelope on the drawing. Two-side sealed collar note: after driving the eccentric collar tight, lock the collar set screw against its recess and verify the collar cannot be turned by hand; a collar that was merely pressed on without the eccentric bite spins on the shaft and frets it within hours. Direction rule for YEL-212-207-2F: the eccentric collar self-tightens in the shaft's running direction, so mark rotation at mounting; the 61.912499999999994 mm shaft must be free of burrs under the collar or the eccentric cannot bed flat.", "applications": [ "heavy agricultural and harvesting equipment", "forestry and chipper drives", "one-direction bulk conveyor shafts" ], "failure_modes": [ "burr or paint under the eccentric faces prevents full bite, leaving an eccentric preload that runs hot", "collar forced on a reversing application repeatedly loads and unloads the eccentric, fretting both parts", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Overall width 77.8 mm includes collar space — a housing sized for a grub-screw insert of the same OD can be too narrow axially for the YEL collar.", "Never pin or weld the eccentric collar: the controlled eccentric friction is the locking principle, and pinning turns a demountable insert into a shaft-replacement job.", "The eccentric collar is handed to running direction; fit it wrong on the 61.912499999999994 mm shaft and self-tightening becomes self-loosening. Mark the shaft rotation before stripping any YEL2 collar unit.", "The 52.7/36 kN figures belong specifically to YEL 212-207-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YEL-212-207-2F?", "a": "Boundary dimensions: bore 61.912499999999994 mm, sphered OD 110 mm, overall width 61.9 mm (77.8 mm with the collar); weight 1600 g. Loads: dynamic 52.7 kN, static 36 kN, fatigue 1.53 kN; the only published speed is the 3,400 r/min limiting value." }, { "q": "What does the designation YEL 212-207-2F mean?", "a": "YEL means collar locking instead of grub screws — fit the eccentric collar, turn it in the rotation direction until it grips, then lock the collar's own setscrew; the inner ring is extended on both sides. inch bore code -207 decodes as 2\" +7/16, i.e. 61.912 mm; the metric coded size YEL 212 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "What is the difference between YET and YEL?", "a": "YET has the inner ring extended on one side; YEL extends it on both sides. Both lock with the eccentric collar and share bore/OD geometry; the sealed -2F executions sit in the YEL listings." }, { "q": "Can eccentric-collar bearings run in both directions?", "a": "They are intended for one predominant running direction; true reversing drives can unwind the eccentric. For bidirectional or vibrating shafts choose grub-screw or SKF ConCentra (YSP) locking." } ], "cross_ref": [ { "equiv_sku": "YEL", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YEL-212-207-2F", "YEL 212-207-2F" ], "locale_variants": {} }, { "sku": "YSPAG-205", "brand": "SKF", "manufacturer_designation": "YSPAG 205", "series": "YSP2-series", "type": "insert", "d_mm": 25, "D_mm": 52, "B_mm": 33.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 1500, "max_rpm": 1500, "weight_g": 180, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSPAG 205 is SKF's 25 mm-bore SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring in the YSP2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 25x52x33.2 mm. The ConCentra principle replaces point or eccentric clamping: a stepped sleeve between shaft and inner ring is driven axially to contract uniformly, concentric with the sphered-OD sealed ball insert. the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant. Envelope 25x52x33.2 mm (0.984x2.047x1.307 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,500 r/min; mass 180 g. Capacity density: 14 kN from 0.180 kg of bearing steel is about 77.778 kN per kilogram, and per width millimetre the 33.2 mm unit carries 0.422 kN of dynamic capacity. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 33.7 mm, d2 41.7 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Spherical-seat note in numbers: the 52 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 38.5 = 120.951 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Envelope arithmetic: the radial section from 25 mm bore to 52 mm OD is 13.5 mm; dividing C 14 kN by that section gives 1.037 kN per section millimetre, and the 33.2 mm overall width is 2.459x the section. Outer-vs-overall width: the outer ring is 15 mm wide inside the 33.2 mm total, so the extended inner ring accounts for 0.548 of the overall width (9.1 mm of axial projection per side). Sleeve geometry: the ConCentra stepped sleeve occupies the symmetric extension up to the 33.2 mm overall width while the sphered outer ring stays 15 mm wide — uniform sleeve contraction is why run-out stays low at 25 mm bore.", "applications": [ "vibrating conveyors and sieves where screws loosen", "high-speed textile and processing rollers", "fan and blower positions sensitive to imbalance" ], "failure_modes": [ "stepped sleeve driven crooked scores the shaft and leaves one clamping arc unloaded", "undersized/over-toleranced shaft never reaches full sleeve grip despite correct drive-up", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 25 mm shaft.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 33.2 mm-wide sleeve causes a local unclamped arc that later frets.", "Ordering discipline for the 25 mm size: the chapter lists several executions side by side (YSP2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSPAG-205?", "a": "YSPAG 205 measures 25 mm bore x 52 mm OD x 33.2 mm overall width (outer ring 15 mm wide), 0.984 x 2.047 x 1.307 in; mass about 180 g. SKF 17000 ratings: C 14 kN, C0 7.8 kN, Pu 0.335 kN, limiting speed 1,500 r/min." }, { "q": "What does the designation YSPAG 205 mean?", "a": "the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." }, { "q": "When should I choose YSP over YAR or YEL?", "a": "Choose ConCentra for high run-out accuracy, vibrating or reversing shafts, and shafts that must not be marked: fans, vibrating conveyors, sieves and balanced rotors. It needs the correct sleeve and drive procedure rather than simple screw tightening." } ], "cross_ref": [ { "equiv_sku": "YSP-205-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x33.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 205 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSPAG-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x33.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 205-100 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSP-205-100-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x33.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 205-100 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSPAG-205", "YSPAG 205" ], "locale_variants": {} }, { "sku": "YSP-205-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 205 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 25, "D_mm": 52, "B_mm": 33.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSP 205 SB-2F is SKF's 25 mm-bore SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring in the YSP2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 25x52x33.2 mm. The ConCentra principle replaces point or eccentric clamping: a stepped sleeve between shaft and inner ring is driven axially to contract uniformly, concentric with the sphered-OD sealed ball insert. the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 25x52x33.2 mm (0.984x2.047x1.307 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 7,000 r/min; mass 190 g. Grease-life arithmetic is dominated by speed: at dn approx 2.69x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Imperial procurement cross-check: 0.984 in bore, 2.047 in OD, 1.307 in overall width; the 190 g mass converts to 0.190 kg (6.7 oz) for the bill of materials. Bore-to-OD planning: OD 52 over bore 25 is a 2.08x step, while bore/overall-width gives 0.753; the spherical seat in the matching Y-housing must be specified to the 52 mm OD, not to a cylindrical housing bore. Spherical-seat note in numbers: the 52 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 38.5 = 120.951 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fatigue-limit check: Pu 0.335 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YSP 205 SB-2F — most belt-driven mounted-unit loads sit comfortably under 2.393 % of C. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Reuse note for YSP-205-SB-2F: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 25 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "fan and blower positions sensitive to imbalance", "high-speed textile and processing rollers", "food and packaging conveyors" ], "failure_modes": [ "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "undersized/over-toleranced shaft never reaches full sleeve grip despite correct drive-up", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 25 mm shaft.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 33.2 mm-wide sleeve causes a local unclamped arc that later frets.", "Catalogue ratings belong to YSP 205 SB-2F as the concentra two f execution; other order numbers of the YSP 205 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-205-SB-2F?", "a": "YSP 205 SB-2F measures 25 mm bore x 52 mm OD x 33.2 mm overall width (outer ring 15 mm wide), 0.984 x 2.047 x 1.307 in; mass about 190 g. SKF 17000 ratings: C 14 kN, C0 7.8 kN, Pu 0.335 kN, limiting speed 7,000 r/min." }, { "q": "What does the designation YSP 205 SB-2F mean?", "a": "the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the size code 205 carries the usual bore arithmetic — 25 mm — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "When should I choose YSP over YAR or YEL?", "a": "Choose ConCentra for high run-out accuracy, vibrating or reversing shafts, and shafts that must not be marked: fans, vibrating conveyors, sieves and balanced rotors. It needs the correct sleeve and drive procedure rather than simple screw tightening." }, { "q": "What does SB mean in YSP 205 SB-2F?", "a": "SB identifies the ConCentra ball bearing with a shortened inner ring; the overall width is shorter than the non-SB ConCentra design while keeping the concentric sleeve lock and the -2F seal/flinger package." } ], "cross_ref": [ { "equiv_sku": "YSPAG-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x33.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 205 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSPAG-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x33.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 205-100 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSP-205-100-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25x52x33.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 205-100 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-205-SB-2F", "YSP 205 SB-2F" ], "locale_variants": {} }, { "sku": "YSPAG-206", "brand": "SKF", "manufacturer_designation": "YSPAG 206", "series": "YSP2-series", "type": "insert", "d_mm": 30, "D_mm": 62, "B_mm": 37.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 1200, "max_rpm": 1200, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSPAG 206 is a SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, 30x62x37.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction is a sealed deep-groove insert, a symmetrically extended inner ring and the stepped ConCentra sleeve — uniform grip, minimal run-out, no shaft damage from screw points or an eccentric mass. reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 30x62x37.2 mm (1.181x2.441x1.465 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,200 r/min; mass 300 g. Imperial procurement cross-check: 1.181 in bore, 2.441 in OD, 1.465 in overall width; the 300 g mass converts to 0.300 kg (10.6 oz) for the bill of materials. Fillet discipline: the printed minimum-fillet limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 30x62 mm insert on its chamfer tilts the whole spherical seat. Grease-life arithmetic is dominated by speed: at dn approx 0.55x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the AG variant caps speed so aggressively, and high-temperature mounts shorten both even when load is light. Mass-to-load ratio for YSPAG-206: 15.385 g of catalogue mass per rated kN of C, and 10 g per millimetre of bore — useful when comparing executions of the same 30x62 mm envelope on the drawing. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 39.7 mm, d2 48 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Sleeve geometry: the ConCentra stepped sleeve occupies the symmetric extension up to the 37.2 mm overall width while the sphered outer ring stays 18 mm wide — uniform sleeve contraction is why run-out stays low at 30 mm bore.", "applications": [ "high-speed textile and processing rollers", "food and packaging conveyors", "fan and blower positions sensitive to imbalance" ], "failure_modes": [ "undersized/over-toleranced shaft never reaches full sleeve grip despite correct drive-up", "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 30 mm shaft.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 37.2 mm-wide sleeve causes a local unclamped arc that later frets.", "Catalogue ratings belong to YSPAG 206 as the concentra two ag execution; other order numbers of the YSPAG 206 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSPAG-206?", "a": "The catalogue envelope is 30x62x37.2 mm with a spherical outside surface; mass 300 g. Ratings C 19.5/11.2 kN, Pu 0.475 kN, limiting speed 1,200 r/min." }, { "q": "What does the designation YSPAG 206 mean?", "a": "reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." } ], "cross_ref": [ { "equiv_sku": "YSP-206-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x37.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 206 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSPAG-206-103", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x37.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 206-103 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSP-206-103-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x37.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 206-103 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSPAG-206", "YSPAG 206" ], "locale_variants": {} }, { "sku": "YSP-206-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 206 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 30, "D_mm": 62, "B_mm": 37.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 310, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSP 206 SB-2F is a SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, 30x62x37.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction is a sealed deep-groove insert, a symmetrically extended inner ring and the stepped ConCentra sleeve — uniform grip, minimal run-out, no shaft damage from screw points or an eccentric mass. reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 30x62x37.2 mm (1.181x2.441x1.465 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 310 g. The s1 23.2 mm dimension is printed for the locking zone — the pre-drive position of the ConCentra stepped sleeve — and it is verified at mounting, not recoverable from d/D/B alone. Grease-life arithmetic is dominated by speed: at dn approx 2.90x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Envelope arithmetic: the radial section from 30 mm bore to 62 mm OD is 16 mm; dividing C 19.5 kN by that section gives 1.219 kN per section millimetre, and the 37.2 mm overall width is 2.325x the section. Selection figures for YSP 206 SB-2F: C0/C is 0.574, Pu 0.475 kN is 2.436 % of the 19.5 kN dynamic rating, and the 310 g catalogue mass works out to roughly 10.333 g per millimetre of the 30 mm bore. Imperial procurement cross-check: 1.181 in bore, 2.441 in OD, 1.465 in overall width; the 310 g mass converts to 0.310 kg (10.9 oz) for the bill of materials. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Reuse note for YSP-206-SB-2F: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 30 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "high-speed textile and processing rollers", "vibrating conveyors and sieves where screws loosen", "fan and blower positions sensitive to imbalance" ], "failure_modes": [ "undersized/over-toleranced shaft never reaches full sleeve grip despite correct drive-up", "stepped sleeve driven crooked scores the shaft and leaves one clamping arc unloaded", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 30 mm shaft.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 37.2 mm-wide sleeve causes a local unclamped arc that later frets.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "Catalogue ratings belong to YSP 206 SB-2F as the concentra two f execution; other order numbers of the YSP 206 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-206-SB-2F?", "a": "The catalogue envelope is 30x62x37.2 mm with a spherical outside surface; mass 310 g. Ratings C 19.5/11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YSP 206 SB-2F mean?", "a": "reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. the size code 206 carries the usual bore arithmetic — 30 mm (code 06 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." }, { "q": "When should I choose YSP over YAR or YEL?", "a": "Choose ConCentra for high run-out accuracy, vibrating or reversing shafts, and shafts that must not be marked: fans, vibrating conveyors, sieves and balanced rotors. It needs the correct sleeve and drive procedure rather than simple screw tightening." } ], "cross_ref": [ { "equiv_sku": "YSPAG-206", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x37.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 206 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSPAG-206-103", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x37.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 206-103 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSP-206-103-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30x62x37.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 206-103 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.162499999999998 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-206-SB-2F", "YSP 206 SB-2F" ], "locale_variants": {} }, { "sku": "YSPAG-207", "brand": "SKF", "manufacturer_designation": "YSPAG 207", "series": "YSP2-series", "type": "insert", "d_mm": 35, "D_mm": 72, "B_mm": 39.7, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSPAG 207 is a SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, 35x72x39.7 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction is a sealed deep-groove insert, a symmetrically extended inner ring and the stepped ConCentra sleeve — uniform grip, minimal run-out, no shaft damage from screw points or an eccentric mass. reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 35x72x39.7 mm (1.378x2.835x1.563 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,100 r/min; mass 440 g. Outer-vs-overall width: the outer ring is 19 mm wide inside the 39.7 mm total, so the extended inner ring accounts for 0.521 of the overall width (10.35 mm of axial projection per side). Capacity density: 25.5 kN from 0.440 kg of bearing steel is about 57.955 kN per kilogram, and per width millimetre the 39.7 mm unit carries 0.642 kN of dynamic capacity. Fatigue-limit check: Pu 0.655 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YSPAG 207 — most belt-driven mounted-unit loads sit comfortably under 2.569 % of C. The s1 24.5 mm dimension is printed for the locking zone — the pre-drive position of the ConCentra stepped sleeve — and it is verified at mounting, not recoverable from d/D/B alone. Static-first planning: the 0.385 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 35 mm shaft, not the 25.5 kN L10 value. Sleeve geometry: the ConCentra stepped sleeve occupies the symmetric extension up to the 39.7 mm overall width while the sphered outer ring stays 19 mm wide — uniform sleeve contraction is why run-out stays low at 35 mm bore.", "applications": [ "vibrating conveyors and sieves where screws loosen", "fan and blower positions sensitive to imbalance", "high-speed textile and processing rollers" ], "failure_modes": [ "stepped sleeve driven crooked scores the shaft and leaves one clamping arc unloaded", "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 39.7 mm-wide sleeve causes a local unclamped arc that later frets.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 35 mm shaft.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The 25.5/15.3 kN figures belong specifically to YSPAG 207; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSPAG-207?", "a": "The catalogue envelope is 35x72x39.7 mm with a spherical outside surface; mass 440 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 1,100 r/min." }, { "q": "What does the designation YSPAG 207 mean?", "a": "reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "What does SB mean in YSPAG 207?", "a": "SB identifies the ConCentra ball bearing with a shortened inner ring; the overall width is shorter than the non-SB ConCentra design while keeping the concentric sleeve lock and the -2F seal/flinger package." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." } ], "cross_ref": [ { "equiv_sku": "YSP-207-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x39.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 207 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSPAG-207-106", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x39.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 207-106 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSP-207-106-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x39.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 207-106 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSPAG-207", "YSPAG 207" ], "locale_variants": {} }, { "sku": "YSP-207-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 207 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 35, "D_mm": 72, "B_mm": 39.7, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSP 207 SB-2F is a SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, 35x72x39.7 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction is a sealed deep-groove insert, a symmetrically extended inner ring and the stepped ConCentra sleeve — uniform grip, minimal run-out, no shaft damage from screw points or an eccentric mass. reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 35x72x39.7 mm (1.378x2.835x1.563 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 450 g. Grease-life arithmetic is dominated by speed: at dn approx 2.84x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Bore-to-OD planning: OD 72 over bore 35 is a 2.057x step, while bore/overall-width gives 0.882; the spherical seat in the matching Y-housing must be specified to the 72 mm OD, not to a cylindrical housing bore. Imperial procurement cross-check: 1.378 in bore, 2.835 in OD, 1.563 in overall width; the 450 g mass converts to 0.450 kg (15.9 oz) for the bill of materials. Mass-to-load ratio for YSP-207-SB-2F: 17.647 g of catalogue mass per rated kN of C, and 12.857 g per millimetre of bore — useful when comparing executions of the same 35x72 mm envelope on the drawing. Selection figures for YSP 207 SB-2F: C0/C is 0.6, Pu 0.655 kN is 2.569 % of the 25.5 kN dynamic rating, and the 450 g catalogue mass works out to roughly 12.857 g per millimetre of the 35 mm bore. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Reuse note for YSP-207-SB-2F: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 35 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "fan and blower positions sensitive to imbalance", "food and packaging conveyors", "vibrating conveyors and sieves where screws loosen" ], "failure_modes": [ "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 39.7 mm-wide sleeve causes a local unclamped arc that later frets.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 35 mm shaft.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The 25.5/15.3 kN figures belong specifically to YSP 207 SB-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-207-SB-2F?", "a": "The catalogue envelope is 35x72x39.7 mm with a spherical outside surface; mass 450 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 5,300 r/min." }, { "q": "What does the designation YSP 207 SB-2F mean?", "a": "reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. the size code 207 carries the usual bore arithmetic — 35 mm (code 07 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." } ], "cross_ref": [ { "equiv_sku": "YSPAG-207", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x39.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 207 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSPAG-207-106", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x39.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 207-106 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSP-207-106-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 35x72x39.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 207-106 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 35 mm vs 34.925 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-207-SB-2F", "YSP 207 SB-2F" ], "locale_variants": {} }, { "sku": "YSPAG-208", "brand": "SKF", "manufacturer_designation": "YSPAG 208", "series": "YSP2-series", "type": "insert", "d_mm": 40, "D_mm": 80, "B_mm": 43.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 950, "max_rpm": 950, "weight_g": 580, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSPAG 208 is a SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, 40x80x43.1 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction is a sealed deep-groove insert, a symmetrically extended inner ring and the stepped ConCentra sleeve — uniform grip, minimal run-out, no shaft damage from screw points or an eccentric mass. reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 40x80x43.1 mm (1.575x3.15x1.697 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 950 r/min; mass 580 g. Fatigue-limit check: Pu 0.8 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YSPAG 208 — most belt-driven mounted-unit loads sit comfortably under 2.606 % of C. Load balance for documentation: C0 19 kN against C 30.7 kN gives a 0.619 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Pitch-diameter arithmetic: dm = (40+80)/2 = 60 mm; at the 950 r/min limiting speed the ball set runs at dn approx 0.57x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. The s1 26.2 mm dimension is printed for the locking zone — the pre-drive position of the ConCentra stepped sleeve — and it is verified at mounting, not recoverable from d/D/B alone. At the printed limiting speed of 950 r/min the mean diameter dm = 60 mm implies dn about 0.57x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Reuse note for YSPAG-208: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 40 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "fan and blower positions sensitive to imbalance", "high-speed textile and processing rollers", "food and packaging conveyors" ], "failure_modes": [ "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "undersized/over-toleranced shaft never reaches full sleeve grip despite correct drive-up", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 40 mm shaft.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 43.1 mm-wide sleeve causes a local unclamped arc that later frets.", "Ordering discipline for the 40 mm size: the chapter lists several executions side by side (YSP2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSPAG-208?", "a": "The catalogue envelope is 40x80x43.1 mm with a spherical outside surface; mass 580 g. Ratings C 30.7/19 kN, Pu 0.8 kN, limiting speed 950 r/min." }, { "q": "What does the designation YSPAG 208 mean?", "a": "reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "When should I choose YSP over YAR or YEL?", "a": "Choose ConCentra for high run-out accuracy, vibrating or reversing shafts, and shafts that must not be marked: fans, vibrating conveyors, sieves and balanced rotors. It needs the correct sleeve and drive procedure rather than simple screw tightening." }, { "q": "What does SB mean in YSPAG 208?", "a": "SB identifies the ConCentra ball bearing with a shortened inner ring; the overall width is shorter than the non-SB ConCentra design while keeping the concentric sleeve lock and the -2F seal/flinger package." } ], "cross_ref": [ { "equiv_sku": "YELAG-208", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x43.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 208 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-208-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x43.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 208-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-208-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x43.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 208-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSP-208-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x43.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 208 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSPAG-208", "YSPAG 208" ], "locale_variants": {} }, { "sku": "YSP-208-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 208 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 40, "D_mm": 80, "B_mm": 43.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 590, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSP 208 SB-2F is a SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, 40x80x43.1 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction is a sealed deep-groove insert, a symmetrically extended inner ring and the stepped ConCentra sleeve — uniform grip, minimal run-out, no shaft damage from screw points or an eccentric mass. reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 40x80x43.1 mm (1.575x3.15x1.697 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,800 r/min; mass 590 g. Capacity density: 30.7 kN from 0.590 kg of bearing steel is about 52.034 kN per kilogram, and per width millimetre the 43.1 mm unit carries 0.712 kN of dynamic capacity. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 51.8 mm, d2 62 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Spherical-seat note in numbers: the 80 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 60 = 188.496 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Static-first planning: the 0.441 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 40 mm shaft, not the 30.7 kN L10 value. Grease-life arithmetic is dominated by speed: at dn approx 2.88x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Sleeve geometry: the ConCentra stepped sleeve occupies the symmetric extension up to the 43.1 mm overall width while the sphered outer ring stays 21 mm wide — uniform sleeve contraction is why run-out stays low at 40 mm bore.", "applications": [ "vibrating conveyors and sieves where screws loosen", "fan and blower positions sensitive to imbalance", "high-speed textile and processing rollers" ], "failure_modes": [ "stepped sleeve driven crooked scores the shaft and leaves one clamping arc unloaded", "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 43.1 mm-wide sleeve causes a local unclamped arc that later frets.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 40 mm shaft.", "Ordering discipline for the 40 mm size: the chapter lists several executions side by side (YSP2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-208-SB-2F?", "a": "The catalogue envelope is 40x80x43.1 mm with a spherical outside surface; mass 590 g. Ratings C 30.7/19 kN, Pu 0.8 kN, limiting speed 4,800 r/min." }, { "q": "What does the designation YSP 208 SB-2F mean?", "a": "reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. the size code 208 carries the usual bore arithmetic — 40 mm (code 08 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "What does SB mean in YSP 208 SB-2F?", "a": "SB identifies the ConCentra ball bearing with a shortened inner ring; the overall width is shorter than the non-SB ConCentra design while keeping the concentric sleeve lock and the -2F seal/flinger package." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." } ], "cross_ref": [ { "equiv_sku": "YELAG-208", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x43.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 208 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-208-2RF-VL065", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x43.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 208-2RF/VL065 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-208-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x43.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 208-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSPAG-208", "equiv_brand": "SKF", "level": "full", "note": "Same 40x80x43.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 208 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-208-SB-2F", "YSP 208 SB-2F" ], "locale_variants": {} }, { "sku": "YSPAG-209", "brand": "SKF", "manufacturer_designation": "YSPAG 209", "series": "YSP2-series", "type": "insert", "d_mm": 45, "D_mm": 85, "B_mm": 44.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 850, "max_rpm": 850, "weight_g": 640, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSPAG 209 is a SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, 45x85x44.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction is a sealed deep-groove insert, a symmetrically extended inner ring and the stepped ConCentra sleeve — uniform grip, minimal run-out, no shaft damage from screw points or an eccentric mass. reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 45x85x44.2 mm (1.772x3.346x1.74 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 850 r/min; mass 640 g. Fatigue-limit check: Pu 0.915 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YSPAG 209 — most belt-driven mounted-unit loads sit comfortably under 2.756 % of C. Rating split for the maintenance file: dynamic 33.2 kN (L10), static 21.6 kN (s0 shock check), fatigue 0.915 kN (adjusted life) — three separate uses for YSPAG 209, none interchangeable with another. Grease-life arithmetic is dominated by speed: at dn approx 0.55x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the AG variant caps speed so aggressively, and high-temperature mounts shorten both even when load is light. The s1 26.7 mm dimension is printed for the locking zone — the pre-drive position of the ConCentra stepped sleeve — and it is verified at mounting, not recoverable from d/D/B alone. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 56.8 mm, d2 67 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Sleeve geometry: the ConCentra stepped sleeve occupies the symmetric extension up to the 44.2 mm overall width while the sphered outer ring stays 22 mm wide — uniform sleeve contraction is why run-out stays low at 45 mm bore.", "applications": [ "fan and blower positions sensitive to imbalance", "vibrating conveyors and sieves where screws loosen", "food and packaging conveyors" ], "failure_modes": [ "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "stepped sleeve driven crooked scores the shaft and leaves one clamping arc unloaded", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 44.2 mm-wide sleeve causes a local unclamped arc that later frets.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 45 mm shaft.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The 33.2/21.6 kN figures belong specifically to YSPAG 209; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSPAG-209?", "a": "The catalogue envelope is 45x85x44.2 mm with a spherical outside surface; mass 640 g. Ratings C 33.2/21.6 kN, Pu 0.915 kN, limiting speed 850 r/min." }, { "q": "What does the designation YSPAG 209 mean?", "a": "reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." }, { "q": "When should I choose YSP over YAR or YEL?", "a": "Choose ConCentra for high run-out accuracy, vibrating or reversing shafts, and shafts that must not be marked: fans, vibrating conveyors, sieves and balanced rotors. It needs the correct sleeve and drive procedure rather than simple screw tightening." } ], "cross_ref": [ { "equiv_sku": "YSP-209-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 45x85x44.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 209 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSPAG-209", "YSPAG 209" ], "locale_variants": {} }, { "sku": "YSP-209-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 209 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 45, "D_mm": 85, "B_mm": 44.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 660, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSP2 series order number YSP 209 SB-2F is a SKF insert bearing (Y-bearing) for a 45 mm shaft: SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 85 mm. Inside is a capped ball insert whose extended inner ring tapers onto a multi-step locking sleeve; the sleeve grips the shaft around its full circumference and the spherical outer ring pivots in the housing. YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 45x85x44.2 mm (1.772x3.346x1.74 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 660 g. Load balance for documentation: C0 21.6 kN against C 33.2 kN gives a 0.651 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Static-first planning: the 0.489 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 45 mm shaft, not the 33.2 kN L10 value. Speed ceiling of 4,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Envelope arithmetic: the radial section from 45 mm bore to 85 mm OD is 20 mm; dividing C 33.2 kN by that section gives 1.66 kN per section millimetre, and the 44.2 mm overall width is 2.21x the section. Pitch-diameter arithmetic: dm = (45+85)/2 = 65 mm; at the 4,300 r/min limiting speed the ball set runs at dn approx 2.79x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Sleeve geometry: the ConCentra stepped sleeve occupies the symmetric extension up to the 44.2 mm overall width while the sphered outer ring stays 22 mm wide — uniform sleeve contraction is why run-out stays low at 45 mm bore.", "applications": [ "high-speed textile and processing rollers", "fan and blower positions sensitive to imbalance", "food and packaging conveyors" ], "failure_modes": [ "undersized/over-toleranced shaft never reaches full sleeve grip despite correct drive-up", "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 45 mm shaft.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 44.2 mm-wide sleeve causes a local unclamped arc that later frets.", "Catalogue ratings belong to YSP 209 SB-2F as the concentra two f execution; other order numbers of the YSP 209 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-209-SB-2F?", "a": "Boundary dimensions: bore 45 mm, sphered OD 85 mm, overall width 44.2 mm; weight 660 g. Loads: dynamic 33.2 kN, static 21.6 kN, fatigue 0.915 kN; the only published speed is the 4,300 r/min limiting value." }, { "q": "What does the designation YSP 209 SB-2F mean?", "a": "YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. the size code 209 carries the usual bore arithmetic — 45 mm (code 09 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "When should I choose YSP over YAR or YEL?", "a": "Choose ConCentra for high run-out accuracy, vibrating or reversing shafts, and shafts that must not be marked: fans, vibrating conveyors, sieves and balanced rotors. It needs the correct sleeve and drive procedure rather than simple screw tightening." }, { "q": "What does SB mean in YSP 209 SB-2F?", "a": "SB identifies the ConCentra ball bearing with a shortened inner ring; the overall width is shorter than the non-SB ConCentra design while keeping the concentric sleeve lock and the -2F seal/flinger package." } ], "cross_ref": [ { "equiv_sku": "YSPAG-209", "equiv_brand": "SKF", "level": "full", "note": "Same 45x85x44.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 209 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-209-SB-2F", "YSP 209 SB-2F" ], "locale_variants": {} }, { "sku": "YSPAG-210", "brand": "SKF", "manufacturer_designation": "YSPAG 210", "series": "YSP2-series", "type": "insert", "d_mm": 50, "D_mm": 90, "B_mm": 46.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 800, "max_rpm": 800, "weight_g": 720, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSPAG 210 is SKF's 50 mm-bore SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring in the YSP2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 50x90x46.2 mm. The ConCentra principle replaces point or eccentric clamping: a stepped sleeve between shaft and inner ring is driven axially to contract uniformly, concentric with the sphered-OD sealed ball insert. the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant. Envelope 50x90x46.2 mm (1.969x3.543x1.819 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 800 r/min; mass 720 g. Capacity density: 35.1 kN from 0.720 kg of bearing steel is about 48.75 kN per kilogram, and per width millimetre the 46.2 mm unit carries 0.76 kN of dynamic capacity. Rating split for the maintenance file: dynamic 35.1 kN (L10), static 23.2 kN (s0 shock check), fatigue 0.98 kN (adjusted life) — three separate uses for YSPAG 210, none interchangeable with another. Imperial procurement cross-check: 1.969 in bore, 3.543 in OD, 1.819 in overall width; the 720 g mass converts to 0.720 kg (25.4 oz) for the bill of materials. Speed ceiling of 800 r/min is the catalogue mechanical limit for THIS execution; the AG agricultural derate is deliberate, so real fan duty is planned well below it. Spherical-seat note in numbers: the 90 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 70 = 219.911 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Sleeve geometry: the ConCentra stepped sleeve occupies the symmetric extension up to the 46.2 mm overall width while the sphered outer ring stays 22 mm wide — uniform sleeve contraction is why run-out stays low at 50 mm bore.", "applications": [ "vibrating conveyors and sieves where screws loosen", "fan and blower positions sensitive to imbalance", "high-speed textile and processing rollers" ], "failure_modes": [ "stepped sleeve driven crooked scores the shaft and leaves one clamping arc unloaded", "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 46.2 mm-wide sleeve causes a local unclamped arc that later frets.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 50 mm shaft.", "Ordering discipline for the 50 mm size: the chapter lists several executions side by side (YSP2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSPAG-210?", "a": "YSPAG 210 measures 50 mm bore x 90 mm OD x 46.2 mm overall width (outer ring 22 mm wide), 1.969 x 3.543 x 1.819 in; mass about 720 g. SKF 17000 ratings: C 35.1 kN, C0 23.2 kN, Pu 0.98 kN, limiting speed 800 r/min." }, { "q": "What does the designation YSPAG 210 mean?", "a": "the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant." }, { "q": "What does SB mean in YSPAG 210?", "a": "SB identifies the ConCentra ball bearing with a shortened inner ring; the overall width is shorter than the non-SB ConCentra design while keeping the concentric sleeve lock and the -2F seal/flinger package." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." } ], "cross_ref": [ { "equiv_sku": "YSP-210-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x46.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 210 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSPAG-210", "YSPAG 210" ], "locale_variants": {} }, { "sku": "YSP-210-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 210 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 50, "D_mm": 90, "B_mm": 46.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 740, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSP2 series order number YSP 210 SB-2F is a SKF insert bearing (Y-bearing) for a 50 mm shaft: SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 90 mm. Inside is a capped ball insert whose extended inner ring tapers onto a multi-step locking sleeve; the sleeve grips the shaft around its full circumference and the spherical outer ring pivots in the housing. YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 50x90x46.2 mm (1.969x3.543x1.819 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,000 r/min; mass 740 g. Rating split for the maintenance file: dynamic 35.1 kN (L10), static 23.2 kN (s0 shock check), fatigue 0.98 kN (adjusted life) — three separate uses for YSP 210 SB-2F, none interchangeable with another. Pitch-diameter arithmetic: dm = (50+90)/2 = 70 mm; at the 4,000 r/min limiting speed the ball set runs at dn approx 2.80x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Static-first planning: the 0.502 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 50 mm shaft, not the 35.1 kN L10 value. The s1 27.7 mm dimension is printed for the locking zone — the pre-drive position of the ConCentra stepped sleeve — and it is verified at mounting, not recoverable from d/D/B alone. Envelope arithmetic: the radial section from 50 mm bore to 90 mm OD is 20 mm; dividing C 35.1 kN by that section gives 1.755 kN per section millimetre, and the 46.2 mm overall width is 2.31x the section. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Reuse note for YSP-210-SB-2F: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 50 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "fan and blower positions sensitive to imbalance", "food and packaging conveyors", "vibrating conveyors and sieves where screws loosen" ], "failure_modes": [ "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 46.2 mm-wide sleeve causes a local unclamped arc that later frets.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 50 mm shaft.", "The 35.1/23.2 kN figures belong specifically to YSP 210 SB-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-210-SB-2F?", "a": "Boundary dimensions: bore 50 mm, sphered OD 90 mm, overall width 46.2 mm; weight 740 g. Loads: dynamic 35.1 kN, static 23.2 kN, fatigue 0.98 kN; the only published speed is the 4,000 r/min limiting value." }, { "q": "What does the designation YSP 210 SB-2F mean?", "a": "YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. the size code 210 carries the usual bore arithmetic — 50 mm (code 10 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." } ], "cross_ref": [ { "equiv_sku": "YSPAG-210", "equiv_brand": "SKF", "level": "full", "note": "Same 50x90x46.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 210 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-210-SB-2F", "YSP 210 SB-2F" ], "locale_variants": {} }, { "sku": "YSP-211-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 211 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 55, "D_mm": 100, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 980, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSP2 series order number YSP 211 SB-2F is a SKF insert bearing (Y-bearing) for a 55 mm shaft: SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 100 mm. Inside is a capped ball insert whose extended inner ring tapers onto a multi-step locking sleeve; the sleeve grips the shaft around its full circumference and the spherical outer ring pivots in the housing. YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. the size code 211 carries the usual bore arithmetic — 55 mm (code 11 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 55x100x49.2 mm (2.165x3.937x1.937 in), outer ring 25 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,600 r/min; mass 980 g. Width accounting on this execution: 49.2 mm overall and 25 mm outer-ring width leave the housing designer 24.2 mm of inner-ring projection to accommodate the locking arrangement. Fatigue-limit check: Pu 1.25 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YSP 211 SB-2F — most belt-driven mounted-unit loads sit comfortably under 2.867 % of C. Outer-vs-overall width: the outer ring is 25 mm wide inside the 49.2 mm total, so the extended inner ring accounts for 0.492 of the overall width (12.1 mm of axial projection per side). Spherical-seat note in numbers: the 100 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 77.5 = 243.473 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Rating split for the maintenance file: dynamic 43.6 kN (L10), static 29 kN (s0 shock check), fatigue 1.25 kN (adjusted life) — three separate uses for YSP 211 SB-2F, none interchangeable with another. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Sleeve geometry: the ConCentra stepped sleeve occupies the symmetric extension up to the 49.2 mm overall width while the sphered outer ring stays 25 mm wide — uniform sleeve contraction is why run-out stays low at 55 mm bore.", "applications": [ "vibrating conveyors and sieves where screws loosen", "high-speed textile and processing rollers", "fan and blower positions sensitive to imbalance" ], "failure_modes": [ "stepped sleeve driven crooked scores the shaft and leaves one clamping arc unloaded", "undersized/over-toleranced shaft never reaches full sleeve grip despite correct drive-up", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 49.2 mm-wide sleeve causes a local unclamped arc that later frets.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 55 mm shaft.", "The 43.6/29 kN figures belong specifically to YSP 211 SB-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-211-SB-2F?", "a": "Boundary dimensions: bore 55 mm, sphered OD 100 mm, overall width 49.2 mm; weight 980 g. Loads: dynamic 43.6 kN, static 29 kN, fatigue 1.25 kN; the only published speed is the 3,600 r/min limiting value." }, { "q": "What does the designation YSP 211 SB-2F mean?", "a": "YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. the size code 211 carries the usual bore arithmetic — 55 mm (code 11 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." }, { "q": "When should I choose YSP over YAR or YEL?", "a": "Choose ConCentra for high run-out accuracy, vibrating or reversing shafts, and shafts that must not be marked: fans, vibrating conveyors, sieves and balanced rotors. It needs the correct sleeve and drive procedure rather than simple screw tightening." } ], "cross_ref": [ { "equiv_sku": "YSP", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-211-SB-2F", "YSP 211 SB-2F" ], "locale_variants": {} }, { "sku": "YSP-212-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 212 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 60, "D_mm": 110, "B_mm": 51.7, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 36, "fatigue_load_limit_kN": 1.53, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSP2 series order number YSP 212 SB-2F is a SKF insert bearing (Y-bearing) for a 60 mm shaft: SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 110 mm. Inside is a capped ball insert whose extended inner ring tapers onto a multi-step locking sleeve; the sleeve grips the shaft around its full circumference and the spherical outer ring pivots in the housing. YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. the size code 212 carries the usual bore arithmetic — 60 mm (code 12 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 60x110x51.7 mm (2.362x4.331x2.035 in), outer ring 26 mm wide, C 52.7 kN, C0 36 kN, Pu 1.53 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,400 r/min; mass 1250 g. Bore-to-OD planning: OD 110 over bore 60 is a 1.833x step, while bore/overall-width gives 1.161; the spherical seat in the matching Y-housing must be specified to the 110 mm OD, not to a cylindrical housing bore. The s1 30.5 mm dimension is printed for the locking zone — the pre-drive position of the ConCentra stepped sleeve — and it is verified at mounting, not recoverable from d/D/B alone. At the printed limiting speed of 3,400 r/min the mean diameter dm = 85 mm implies dn about 2.89x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Fillet discipline: the printed minimum-fillet limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 60x110 mm insert on its chamfer tilts the whole spherical seat. Speed ceiling of 3,400 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Sleeve geometry: the ConCentra stepped sleeve occupies the symmetric extension up to the 51.7 mm overall width while the sphered outer ring stays 26 mm wide — uniform sleeve contraction is why run-out stays low at 60 mm bore.", "applications": [ "heavily vibrating screen and feeder shafts", "large fan positions with dynamic balancing requirements", "process-industry roller beds" ], "failure_modes": [ "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "undersized/over-toleranced shaft never reaches full sleeve grip despite correct drive-up", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 60 mm shaft.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 51.7 mm-wide sleeve causes a local unclamped arc that later frets.", "Ordering discipline for the 60 mm size: the chapter lists several executions side by side (YSP2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-212-SB-2F?", "a": "Boundary dimensions: bore 60 mm, sphered OD 110 mm, overall width 51.7 mm; weight 1250 g. Loads: dynamic 52.7 kN, static 36 kN, fatigue 1.53 kN; the only published speed is the 3,400 r/min limiting value." }, { "q": "What does the designation YSP 212 SB-2F mean?", "a": "YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. the size code 212 carries the usual bore arithmetic — 60 mm (code 12 x 5) — while the leading 2 marks the ISO 15 diameter series 2 sphered-OD envelope. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "When should I choose YSP over YAR or YEL?", "a": "Choose ConCentra for high run-out accuracy, vibrating or reversing shafts, and shafts that must not be marked: fans, vibrating conveyors, sieves and balanced rotors. It needs the correct sleeve and drive procedure rather than simple screw tightening." }, { "q": "What does SB mean in YSP 212 SB-2F?", "a": "SB identifies the ConCentra ball bearing with a shortened inner ring; the overall width is shorter than the non-SB ConCentra design while keeping the concentric sleeve lock and the -2F seal/flinger package." } ], "cross_ref": [ { "equiv_sku": "YSP", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-212-SB-2F", "YSP 212 SB-2F" ], "locale_variants": {} }, { "sku": "YSPAG-205-100", "brand": "SKF", "manufacturer_designation": "YSPAG 205-100", "series": "YSP2-series", "type": "insert", "d_mm": 25.4, "D_mm": 52, "B_mm": 33.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 1500, "max_rpm": 1500, "weight_g": 180, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSPAG 205-100 is a SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, 25.4x52x33.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction is a sealed deep-groove insert, a symmetrically extended inner ring and the stepped ConCentra sleeve — uniform grip, minimal run-out, no shaft damage from screw points or an eccentric mass. reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -100 = 25.4 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 25.4x52x33.2 mm (1x2.047x1.307 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,500 r/min; mass 180 g. Envelope arithmetic: the radial section from 25.4 mm bore to 52 mm OD is 13.3 mm; dividing C 14 kN by that section gives 1.053 kN per section millimetre, and the 33.2 mm overall width is 2.496x the section. Selection figures for YSPAG 205-100: C0/C is 0.557, Pu 0.335 kN is 2.393 % of the 14 kN dynamic rating, and the 180 g catalogue mass works out to roughly 7.087 g per millimetre of the 25.4 mm bore. Pitch-diameter arithmetic: dm = (25.4+52)/2 = 38.7 mm; at the 1,500 r/min limiting speed the ball set runs at dn approx 0.58x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Mass-to-load ratio for YSPAG-205-100: 12.857 g of catalogue mass per rated kN of C, and 7.087 g per millimetre of bore — useful when comparing executions of the same 25.4x52 mm envelope on the drawing. At the printed limiting speed of 1,500 r/min the mean diameter dm = 38.7 mm implies dn about 0.58x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Reuse note for YSPAG-205-100: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 25.4 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "food and packaging conveyors", "fan and blower positions sensitive to imbalance", "vibrating conveyors and sieves where screws loosen" ], "failure_modes": [ "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 25.4 mm shaft.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 33.2 mm-wide sleeve causes a local unclamped arc that later frets.", "Ordering discipline for the 25.4 mm size: the chapter lists several executions side by side (YSP2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSPAG-205-100?", "a": "The catalogue envelope is 25.4x52x33.2 mm with a spherical outside surface; mass 180 g. Ratings C 14/7.8 kN, Pu 0.335 kN, limiting speed 1,500 r/min." }, { "q": "What does the designation YSPAG 205-100 mean?", "a": "reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -100 = 25.4 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "What does SB mean in YSPAG 205-100?", "a": "SB identifies the ConCentra ball bearing with a shortened inner ring; the overall width is shorter than the non-SB ConCentra design while keeping the concentric sleeve lock and the -2F seal/flinger package." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." } ], "cross_ref": [ { "equiv_sku": "YSPAG-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x33.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 205 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSP-205-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x33.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 205 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSP-205-100-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x33.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 205-100 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSPAG-205-100", "YSPAG 205-100" ], "locale_variants": {} }, { "sku": "YSP-205-100-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 205-100 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 25.4, "D_mm": 52, "B_mm": 33.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 180, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSP 205-100 SB-2F is a SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, 25.4x52x33.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction is a sealed deep-groove insert, a symmetrically extended inner ring and the stepped ConCentra sleeve — uniform grip, minimal run-out, no shaft damage from screw points or an eccentric mass. reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -100 = 25.4 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 25.4x52x33.2 mm (1x2.047x1.307 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 7,000 r/min; mass 180 g. Selection figures for YSP 205-100 SB-2F: C0/C is 0.557, Pu 0.335 kN is 2.393 % of the 14 kN dynamic rating, and the 180 g catalogue mass works out to roughly 7.087 g per millimetre of the 25.4 mm bore. Envelope arithmetic: the radial section from 25.4 mm bore to 52 mm OD is 13.3 mm; dividing C 14 kN by that section gives 1.053 kN per section millimetre, and the 33.2 mm overall width is 2.496x the section. Mass-to-load ratio for YSP-205-100-SB-2F: 12.857 g of catalogue mass per rated kN of C, and 7.087 g per millimetre of bore — useful when comparing executions of the same 25.4x52 mm envelope on the drawing. Spherical-seat note in numbers: the 52 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 38.7 = 121.58 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Pitch-diameter arithmetic: dm = (25.4+52)/2 = 38.7 mm; at the 7,000 r/min limiting speed the ball set runs at dn approx 2.71x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Reuse note for YSP-205-100-SB-2F: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 25.4 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "vibrating conveyors and sieves where screws loosen", "food and packaging conveyors", "high-speed textile and processing rollers" ], "failure_modes": [ "stepped sleeve driven crooked scores the shaft and leaves one clamping arc unloaded", "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 33.2 mm-wide sleeve causes a local unclamped arc that later frets.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 25.4 mm shaft.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The 14/7.8 kN figures belong specifically to YSP 205-100 SB-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-205-100-SB-2F?", "a": "The catalogue envelope is 25.4x52x33.2 mm with a spherical outside surface; mass 180 g. Ratings C 14/7.8 kN, Pu 0.335 kN, limiting speed 7,000 r/min." }, { "q": "What does the designation YSP 205-100 SB-2F mean?", "a": "reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -100 = 25.4 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." } ], "cross_ref": [ { "equiv_sku": "YSPAG-205", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x33.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 205 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSP-205-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x33.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 205 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSPAG-205-100", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x52x33.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 205-100 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-205-100-SB-2F", "YSP 205-100 SB-2F" ], "locale_variants": {} }, { "sku": "YSPAG-206-103", "brand": "SKF", "manufacturer_designation": "YSPAG 206-103", "series": "YSP2-series", "type": "insert", "d_mm": 30.162499999999998, "D_mm": 62, "B_mm": 37.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 1200, "max_rpm": 1200, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSP2 series order number YSPAG 206-103 is a SKF insert bearing (Y-bearing) for a 30.162499999999998 mm (1.188 in) shaft: SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 62 mm. Inside is a capped ball insert whose extended inner ring tapers onto a multi-step locking sleeve; the sleeve grips the shaft around its full circumference and the spherical outer ring pivots in the housing. YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. inch bore code -103 decodes as 1\" +3/16, i.e. 30.162 mm; the metric coded size YSPAG 206 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution. Envelope 30.162499999999998x62x37.2 mm (1.188x2.441x1.465 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,200 r/min; mass 300 g. At the printed limiting speed of 1,200 r/min the mean diameter dm = 46.081 mm implies dn about 0.55x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Speed ceiling of 1,200 r/min is the catalogue mechanical limit for THIS execution; the AG agricultural derate is deliberate, so real fan duty is planned well below it. Selection figures for YSPAG 206-103: C0/C is 0.574, Pu 0.475 kN is 2.436 % of the 19.5 kN dynamic rating, and the 300 g catalogue mass works out to roughly 9.946 g per millimetre of the 30.162499999999998 mm bore. Spherical-seat note in numbers: the 62 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 46.081 = 144.768 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Outer-vs-overall width: the outer ring is 18 mm wide inside the 37.2 mm total, so the extended inner ring accounts for 0.516 of the overall width (9.6 mm of axial projection per side). Sleeve geometry: the ConCentra stepped sleeve occupies the symmetric extension up to the 37.2 mm overall width while the sphered outer ring stays 18 mm wide — uniform sleeve contraction is why run-out stays low at 30.162499999999998 mm bore.", "applications": [ "fan and blower positions sensitive to imbalance", "food and packaging conveyors", "vibrating conveyors and sieves where screws loosen" ], "failure_modes": [ "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 30.162499999999998 mm shaft.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 37.2 mm-wide sleeve causes a local unclamped arc that later frets.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "Catalogue ratings belong to YSPAG 206-103 as the concentra two ag execution; other order numbers of the YSPAG 206-103 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSPAG-206-103?", "a": "Boundary dimensions: bore 30.162499999999998 mm, sphered OD 62 mm, overall width 37.2 mm; weight 300 g. Loads: dynamic 19.5 kN, static 11.2 kN, fatigue 0.475 kN; the only published speed is the 1,200 r/min limiting value." }, { "q": "What does the designation YSPAG 206-103 mean?", "a": "YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. inch bore code -103 decodes as 1\" +3/16, i.e. 30.162 mm; the metric coded size YSPAG 206 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution." }, { "q": "What does SB mean in YSPAG 206-103?", "a": "SB identifies the ConCentra ball bearing with a shortened inner ring; the overall width is shorter than the non-SB ConCentra design while keeping the concentric sleeve lock and the -2F seal/flinger package." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." } ], "cross_ref": [ { "equiv_sku": "YSPAG-206", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x37.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 206 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSP-206-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x37.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 206 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSP-206-103-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x37.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 206-103 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSPAG-206-103", "YSPAG 206-103" ], "locale_variants": {} }, { "sku": "YSP-206-103-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 206-103 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 30.162499999999998, "D_mm": 62, "B_mm": 37.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSP 206-103 SB-2F is SKF's 30.162499999999998 mm-bore SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring in the YSP2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 30.162499999999998x62x37.2 mm. The ConCentra principle replaces point or eccentric clamping: a stepped sleeve between shaft and inner ring is driven axially to contract uniformly, concentric with the sphered-OD sealed ball insert. the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the three-digit -103 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 3/16 in = 30.162 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 30.162499999999998x62x37.2 mm (1.188x2.441x1.465 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 300 g. Outer-vs-overall width: the outer ring is 18 mm wide inside the 37.2 mm total, so the extended inner ring accounts for 0.516 of the overall width (9.6 mm of axial projection per side). Fillet discipline: the printed minimum-fillet limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 30.162499999999998x62 mm insert on its chamfer tilts the whole spherical seat. Mass-to-load ratio for YSP-206-103-SB-2F: 15.385 g of catalogue mass per rated kN of C, and 9.946 g per millimetre of bore — useful when comparing executions of the same 30.162499999999998x62 mm envelope on the drawing. Load balance for documentation: C0 11.2 kN against C 19.5 kN gives a 0.574 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Selection figures for YSP 206-103 SB-2F: C0/C is 0.574, Pu 0.475 kN is 2.436 % of the 19.5 kN dynamic rating, and the 300 g catalogue mass works out to roughly 9.946 g per millimetre of the 30.162499999999998 mm bore. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Reuse note for YSP-206-103-SB-2F: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 30.162499999999998 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "vibrating conveyors and sieves where screws loosen", "food and packaging conveyors", "high-speed textile and processing rollers" ], "failure_modes": [ "stepped sleeve driven crooked scores the shaft and leaves one clamping arc unloaded", "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 37.2 mm-wide sleeve causes a local unclamped arc that later frets.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 30.162499999999998 mm shaft.", "The 19.5/11.2 kN figures belong specifically to YSP 206-103 SB-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-206-103-SB-2F?", "a": "YSP 206-103 SB-2F measures 30.162499999999998 mm bore x 62 mm OD x 37.2 mm overall width (outer ring 18 mm wide), 1.188 x 2.441 x 1.465 in; mass about 300 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YSP 206-103 SB-2F mean?", "a": "the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the three-digit -103 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 3/16 in = 30.162 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." } ], "cross_ref": [ { "equiv_sku": "YSPAG-206", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x37.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 206 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSP-206-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x37.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 206 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.162499999999998 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSPAG-206-103", "equiv_brand": "SKF", "level": "full", "note": "Same 30.162499999999998x62x37.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 206-103 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-206-103-SB-2F", "YSP 206-103 SB-2F" ], "locale_variants": {} }, { "sku": "YSPAG-207-104", "brand": "SKF", "manufacturer_designation": "YSPAG 207-104", "series": "YSP2-series", "type": "insert", "d_mm": 31.75, "D_mm": 72, "B_mm": 39.7, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 490, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSPAG 207-104 is SKF's 31.75 mm-bore SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring in the YSP2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 31.75x72x39.7 mm. The ConCentra principle replaces point or eccentric clamping: a stepped sleeve between shaft and inner ring is driven axially to contract uniformly, concentric with the sphered-OD sealed ball insert. the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the three-digit -104 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 4/16 in = 31.75 mm (first digit whole inches, next two sixteenths of an inch). AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant. Envelope 31.75x72x39.7 mm (1.25x2.835x1.563 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,100 r/min; mass 490 g. Load balance for documentation: C0 15.3 kN against C 25.5 kN gives a 0.6 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Fatigue-limit check: Pu 0.655 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YSPAG 207-104 — most belt-driven mounted-unit loads sit comfortably under 2.569 % of C. Mass-to-load ratio for YSPAG-207-104: 19.216 g of catalogue mass per rated kN of C, and 15.433 g per millimetre of bore — useful when comparing executions of the same 31.75x72 mm envelope on the drawing. Pitch-diameter arithmetic: dm = (31.75+72)/2 = 51.875 mm; at the 1,100 r/min limiting speed the ball set runs at dn approx 0.57x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Speed ceiling of 1,100 r/min is the catalogue mechanical limit for THIS execution; the AG agricultural derate is deliberate, so real fan duty is planned well below it. Reuse note for YSPAG-207-104: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 31.75 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "high-speed textile and processing rollers", "vibrating conveyors and sieves where screws loosen", "fan and blower positions sensitive to imbalance" ], "failure_modes": [ "undersized/over-toleranced shaft never reaches full sleeve grip despite correct drive-up", "stepped sleeve driven crooked scores the shaft and leaves one clamping arc unloaded", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 31.75 mm shaft.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 39.7 mm-wide sleeve causes a local unclamped arc that later frets.", "Ordering discipline for the 31.75 mm size: the chapter lists several executions side by side (YSP2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSPAG-207-104?", "a": "YSPAG 207-104 measures 31.75 mm bore x 72 mm OD x 39.7 mm overall width (outer ring 19 mm wide), 1.25 x 2.835 x 1.563 in; mass about 490 g. SKF 17000 ratings: C 25.5 kN, C0 15.3 kN, Pu 0.655 kN, limiting speed 1,100 r/min." }, { "q": "What does the designation YSPAG 207-104 mean?", "a": "the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the three-digit -104 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 4/16 in = 31.75 mm (first digit whole inches, next two sixteenths of an inch). AG marks the agricultural-machinery application execution, built on the sealed both-sides-extended geometry and tuned for the low-speed, shock-laden duty of harvesters, balers and spreaders — note the catalogue prints a much reduced limiting speed for this variant." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." }, { "q": "When should I choose YSP over YAR or YEL?", "a": "Choose ConCentra for high run-out accuracy, vibrating or reversing shafts, and shafts that must not be marked: fans, vibrating conveyors, sieves and balanced rotors. It needs the correct sleeve and drive procedure rather than simple screw tightening." } ], "cross_ref": [ { "equiv_sku": "YSP-207-104-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x39.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 207-104 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSPAG-207-104", "YSPAG 207-104" ], "locale_variants": {} }, { "sku": "YSP-207-104-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 207-104 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 31.75, "D_mm": 72, "B_mm": 39.7, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSP 207-104 SB-2F is a SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, 31.75x72x39.7 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction is a sealed deep-groove insert, a symmetrically extended inner ring and the stepped ConCentra sleeve — uniform grip, minimal run-out, no shaft damage from screw points or an eccentric mass. reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -104 = 31.75 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 31.75x72x39.7 mm (1.25x2.835x1.563 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 500 g. Speed ceiling of 5,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Static-first planning: the 0.385 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 31.75 mm shaft, not the 25.5 kN L10 value. Imperial procurement cross-check: 1.25 in bore, 2.835 in OD, 1.563 in overall width; the 500 g mass converts to 0.500 kg (17.6 oz) for the bill of materials. Load balance for documentation: C0 15.3 kN against C 25.5 kN gives a 0.6 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Rating split for the maintenance file: dynamic 25.5 kN (L10), static 15.3 kN (s0 shock check), fatigue 0.655 kN (adjusted life) — three separate uses for YSP 207-104 SB-2F, none interchangeable with another. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Reuse note for YSP-207-104-SB-2F: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 31.75 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "vibrating conveyors and sieves where screws loosen", "high-speed textile and processing rollers", "fan and blower positions sensitive to imbalance" ], "failure_modes": [ "stepped sleeve driven crooked scores the shaft and leaves one clamping arc unloaded", "undersized/over-toleranced shaft never reaches full sleeve grip despite correct drive-up", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 39.7 mm-wide sleeve causes a local unclamped arc that later frets.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 31.75 mm shaft.", "Ordering discipline for the 31.75 mm size: the chapter lists several executions side by side (YSP2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-207-104-SB-2F?", "a": "The catalogue envelope is 31.75x72x39.7 mm with a spherical outside surface; mass 500 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 5,300 r/min." }, { "q": "What does the designation YSP 207-104 SB-2F mean?", "a": "reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -104 = 31.75 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "When should I choose YSP over YAR or YEL?", "a": "Choose ConCentra for high run-out accuracy, vibrating or reversing shafts, and shafts that must not be marked: fans, vibrating conveyors, sieves and balanced rotors. It needs the correct sleeve and drive procedure rather than simple screw tightening." }, { "q": "What does SB mean in YSP 207-104 SB-2F?", "a": "SB identifies the ConCentra ball bearing with a shortened inner ring; the overall width is shorter than the non-SB ConCentra design while keeping the concentric sleeve lock and the -2F seal/flinger package." } ], "cross_ref": [ { "equiv_sku": "YSPAG-207-104", "equiv_brand": "SKF", "level": "full", "note": "Same 31.75x72x39.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 207-104 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-207-104-SB-2F", "YSP 207-104 SB-2F" ], "locale_variants": {} }, { "sku": "YSPAG-207-106", "brand": "SKF", "manufacturer_designation": "YSPAG 207-106", "series": "YSP2-series", "type": "insert", "d_mm": 34.925, "D_mm": 72, "B_mm": 39.7, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSP2 series order number YSPAG 207-106 is a SKF insert bearing (Y-bearing) for a 34.925 mm (1.375 in) shaft: SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside is a capped ball insert whose extended inner ring tapers onto a multi-step locking sleeve; the sleeve grips the shaft around its full circumference and the spherical outer ring pivots in the housing. YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. inch bore code -106 decodes as 1\" +6/16, i.e. 34.925 mm; the metric coded size YSPAG 207 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution. Envelope 34.925x72x39.7 mm (1.375x2.835x1.563 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,100 r/min; mass 440 g. Load balance for documentation: C0 15.3 kN against C 25.5 kN gives a 0.6 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Selection figures for YSPAG 207-106: C0/C is 0.6, Pu 0.655 kN is 2.569 % of the 25.5 kN dynamic rating, and the 440 g catalogue mass works out to roughly 12.598 g per millimetre of the 34.925 mm bore. Static-first planning: the 0.385 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 34.925 mm shaft, not the 25.5 kN L10 value. Pitch-diameter arithmetic: dm = (34.925+72)/2 = 53.462 mm; at the 1,100 r/min limiting speed the ball set runs at dn approx 0.59x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Rating split for the maintenance file: dynamic 25.5 kN (L10), static 15.3 kN (s0 shock check), fatigue 0.655 kN (adjusted life) — three separate uses for YSPAG 207-106, none interchangeable with another. Reuse note for YSPAG-207-106: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 34.925 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "high-speed textile and processing rollers", "fan and blower positions sensitive to imbalance", "food and packaging conveyors" ], "failure_modes": [ "undersized/over-toleranced shaft never reaches full sleeve grip despite correct drive-up", "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 39.7 mm-wide sleeve causes a local unclamped arc that later frets.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 34.925 mm shaft.", "The 25.5/15.3 kN figures belong specifically to YSPAG 207-106; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSPAG-207-106?", "a": "Boundary dimensions: bore 34.925 mm, sphered OD 72 mm, overall width 39.7 mm; weight 440 g. Loads: dynamic 25.5 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 1,100 r/min limiting value." }, { "q": "What does the designation YSPAG 207-106 mean?", "a": "YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. inch bore code -106 decodes as 1\" +6/16, i.e. 34.925 mm; the metric coded size YSPAG 207 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution." }, { "q": "What does SB mean in YSPAG 207-106?", "a": "SB identifies the ConCentra ball bearing with a shortened inner ring; the overall width is shorter than the non-SB ConCentra design while keeping the concentric sleeve lock and the -2F seal/flinger package." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." } ], "cross_ref": [ { "equiv_sku": "YSPAG-207", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x39.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 207 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSP-207-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x39.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 207 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSP-207-106-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x39.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 207-106 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSPAG-207-106", "YSPAG 207-106" ], "locale_variants": {} }, { "sku": "YSP-207-106-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 207-106 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 34.925, "D_mm": 72, "B_mm": 39.7, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSP 207-106 SB-2F is SKF's 34.925 mm-bore SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring in the YSP2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 34.925x72x39.7 mm. The ConCentra principle replaces point or eccentric clamping: a stepped sleeve between shaft and inner ring is driven axially to contract uniformly, concentric with the sphered-OD sealed ball insert. the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the three-digit -106 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 6/16 in = 34.925 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 34.925x72x39.7 mm (1.375x2.835x1.563 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 450 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 46.1 mm, d2 57 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Fillet discipline: the printed minimum-fillet limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 34.925x72 mm insert on its chamfer tilts the whole spherical seat. Load balance for documentation: C0 15.3 kN against C 25.5 kN gives a 0.6 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Pitch-diameter arithmetic: dm = (34.925+72)/2 = 53.462 mm; at the 5,300 r/min limiting speed the ball set runs at dn approx 2.83x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Width accounting on this execution: 39.7 mm overall and 19 mm outer-ring width leave the housing designer 20.7 mm of inner-ring projection to accommodate the locking arrangement. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Reuse note for YSP-207-106-SB-2F: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 34.925 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "fan and blower positions sensitive to imbalance", "food and packaging conveyors", "vibrating conveyors and sieves where screws loosen" ], "failure_modes": [ "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 34.925 mm shaft.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 39.7 mm-wide sleeve causes a local unclamped arc that later frets.", "Ordering discipline for the 34.925 mm size: the chapter lists several executions side by side (YSP2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-207-106-SB-2F?", "a": "YSP 207-106 SB-2F measures 34.925 mm bore x 72 mm OD x 39.7 mm overall width (outer ring 19 mm wide), 1.375 x 2.835 x 1.563 in; mass about 450 g. SKF 17000 ratings: C 25.5 kN, C0 15.3 kN, Pu 0.655 kN, limiting speed 5,300 r/min." }, { "q": "What does the designation YSP 207-106 SB-2F mean?", "a": "the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the three-digit -106 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 6/16 in = 34.925 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." } ], "cross_ref": [ { "equiv_sku": "YSPAG-207", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x39.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 207 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSP-207-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x39.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 207 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 34.925 mm vs 35 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." }, { "equiv_sku": "YSPAG-207-106", "equiv_brand": "SKF", "level": "full", "note": "Same 34.925x72x39.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 207-106 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-207-106-SB-2F", "YSP 207-106 SB-2F" ], "locale_variants": {} }, { "sku": "YSPAG-207-107", "brand": "SKF", "manufacturer_designation": "YSPAG 207-107", "series": "YSP2-series", "type": "insert", "d_mm": 36.512499999999996, "D_mm": 72, "B_mm": 39.7, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 420, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSPAG 207-107 is a SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, 36.512499999999996x72x39.7 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction is a sealed deep-groove insert, a symmetrically extended inner ring and the stepped ConCentra sleeve — uniform grip, minimal run-out, no shaft damage from screw points or an eccentric mass. reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -107 = 36.512 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 36.512499999999996x72x39.7 mm (1.438x2.835x1.563 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 1,100 r/min; mass 420 g. Fatigue-limit check: Pu 0.655 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YSPAG 207-107 — most belt-driven mounted-unit loads sit comfortably under 2.569 % of C. Mass-to-load ratio for YSPAG-207-107: 16.471 g of catalogue mass per rated kN of C, and 11.503 g per millimetre of bore — useful when comparing executions of the same 36.512499999999996x72 mm envelope on the drawing. Static-first planning: the 0.385 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 36.512499999999996 mm shaft, not the 25.5 kN L10 value. Envelope arithmetic: the radial section from 36.512499999999996 mm bore to 72 mm OD is 17.744 mm; dividing C 25.5 kN by that section gives 1.437 kN per section millimetre, and the 39.7 mm overall width is 2.237x the section. Outer-vs-overall width: the outer ring is 19 mm wide inside the 39.7 mm total, so the extended inner ring accounts for 0.521 of the overall width (10.35 mm of axial projection per side). Reuse note for YSPAG-207-107: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 36.512499999999996 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "fan and blower positions sensitive to imbalance", "food and packaging conveyors", "vibrating conveyors and sieves where screws loosen" ], "failure_modes": [ "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 36.512499999999996 mm shaft.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 39.7 mm-wide sleeve causes a local unclamped arc that later frets.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "Catalogue ratings belong to YSPAG 207-107 as the concentra two ag execution; other order numbers of the YSPAG 207-107 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSPAG-207-107?", "a": "The catalogue envelope is 36.512499999999996x72x39.7 mm with a spherical outside surface; mass 420 g. Ratings C 25.5/15.3 kN, Pu 0.655 kN, limiting speed 1,100 r/min." }, { "q": "What does the designation YSPAG 207-107 mean?", "a": "reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -107 = 36.512 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." } ], "cross_ref": [ { "equiv_sku": "YSP-207-107-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 36.512499999999996x72x39.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 207-107 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSPAG-207-107", "YSPAG 207-107" ], "locale_variants": {} }, { "sku": "YSP-207-107-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 207-107 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 36.512499999999996, "D_mm": 72, "B_mm": 39.7, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 420, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSP2 series order number YSP 207-107 SB-2F is a SKF insert bearing (Y-bearing) for a 36.512499999999996 mm (1.438 in) shaft: SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside is a capped ball insert whose extended inner ring tapers onto a multi-step locking sleeve; the sleeve grips the shaft around its full circumference and the spherical outer ring pivots in the housing. YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. inch bore code -107 decodes as 1\" +7/16, i.e. 36.512 mm; the metric coded size YSP 207 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 36.512499999999996x72x39.7 mm (1.438x2.835x1.563 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 420 g. At the printed limiting speed of 5,300 r/min the mean diameter dm = 54.256 mm implies dn about 2.88x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Fatigue-limit check: Pu 0.655 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YSP 207-107 SB-2F — most belt-driven mounted-unit loads sit comfortably under 2.569 % of C. Static-first planning: the 0.385 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 36.512499999999996 mm shaft, not the 25.5 kN L10 value. Grease-life arithmetic is dominated by speed: at dn approx 2.88x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Bore-to-OD planning: OD 72 over bore 36.512499999999996 is a 1.972x step, while bore/overall-width gives 0.92; the spherical seat in the matching Y-housing must be specified to the 72 mm OD, not to a cylindrical housing bore. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Sleeve geometry: the ConCentra stepped sleeve occupies the symmetric extension up to the 39.7 mm overall width while the sphered outer ring stays 19 mm wide — uniform sleeve contraction is why run-out stays low at 36.512499999999996 mm bore.", "applications": [ "fan and blower positions sensitive to imbalance", "vibrating conveyors and sieves where screws loosen", "food and packaging conveyors" ], "failure_modes": [ "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "stepped sleeve driven crooked scores the shaft and leaves one clamping arc unloaded", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 39.7 mm-wide sleeve causes a local unclamped arc that later frets.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 36.512499999999996 mm shaft.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The 25.5/15.3 kN figures belong specifically to YSP 207-107 SB-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-207-107-SB-2F?", "a": "Boundary dimensions: bore 36.512499999999996 mm, sphered OD 72 mm, overall width 39.7 mm; weight 420 g. Loads: dynamic 25.5 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 5,300 r/min limiting value." }, { "q": "What does the designation YSP 207-107 SB-2F mean?", "a": "YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. inch bore code -107 decodes as 1\" +7/16, i.e. 36.512 mm; the metric coded size YSP 207 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." }, { "q": "When should I choose YSP over YAR or YEL?", "a": "Choose ConCentra for high run-out accuracy, vibrating or reversing shafts, and shafts that must not be marked: fans, vibrating conveyors, sieves and balanced rotors. It needs the correct sleeve and drive procedure rather than simple screw tightening." } ], "cross_ref": [ { "equiv_sku": "YSPAG-207-107", "equiv_brand": "SKF", "level": "full", "note": "Same 36.512499999999996x72x39.7 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 207-107 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-207-107-SB-2F", "YSP 207-107 SB-2F" ], "locale_variants": {} }, { "sku": "YSPAG-208-108", "brand": "SKF", "manufacturer_designation": "YSPAG 208-108", "series": "YSP2-series", "type": "insert", "d_mm": 38.099999999999994, "D_mm": 80, "B_mm": 43.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 950, "max_rpm": 950, "weight_g": 610, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSP2 series order number YSPAG 208-108 is a SKF insert bearing (Y-bearing) for a 38.099999999999994 mm (1.5 in) shaft: SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 80 mm. Inside is a capped ball insert whose extended inner ring tapers onto a multi-step locking sleeve; the sleeve grips the shaft around its full circumference and the spherical outer ring pivots in the housing. YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. inch bore code -108 decodes as 1\" +8/16, i.e. 38.1 mm; the metric coded size YSPAG 208 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution. Envelope 38.099999999999994x80x43.1 mm (1.5x3.15x1.697 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 950 r/min; mass 610 g. At the printed limiting speed of 950 r/min the mean diameter dm = 59.05 mm implies dn about 0.56x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Bore-to-OD planning: OD 80 over bore 38.099999999999994 is a 2.1x step, while bore/overall-width gives 0.884; the spherical seat in the matching Y-housing must be specified to the 80 mm OD, not to a cylindrical housing bore. Spherical-seat note in numbers: the 80 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 59.05 = 185.511 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Load balance for documentation: C0 19 kN against C 30.7 kN gives a 0.619 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Mass-to-load ratio for YSPAG-208-108: 19.87 g of catalogue mass per rated kN of C, and 16.01 g per millimetre of bore — useful when comparing executions of the same 38.099999999999994x80 mm envelope on the drawing. Reuse note for YSPAG-208-108: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 38.099999999999994 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "fan and blower positions sensitive to imbalance", "food and packaging conveyors", "vibrating conveyors and sieves where screws loosen" ], "failure_modes": [ "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 43.1 mm-wide sleeve causes a local unclamped arc that later frets.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 38.099999999999994 mm shaft.", "The 30.7/19 kN figures belong specifically to YSPAG 208-108; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSPAG-208-108?", "a": "Boundary dimensions: bore 38.099999999999994 mm, sphered OD 80 mm, overall width 43.1 mm; weight 610 g. Loads: dynamic 30.7 kN, static 19 kN, fatigue 0.8 kN; the only published speed is the 950 r/min limiting value." }, { "q": "What does the designation YSPAG 208-108 mean?", "a": "YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. inch bore code -108 decodes as 1\" +8/16, i.e. 38.1 mm; the metric coded size YSPAG 208 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." } ], "cross_ref": [ { "equiv_sku": "YELAG-208-108", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x43.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 208-108 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-208-108-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x43.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 208-108-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSP-208-108-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x43.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 208-108 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSPAG-208-108", "YSPAG 208-108" ], "locale_variants": {} }, { "sku": "YSP-208-108-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 208-108 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 38.099999999999994, "D_mm": 80, "B_mm": 43.1, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 620, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSP 208-108 SB-2F is SKF's 38.099999999999994 mm-bore SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring in the YSP2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 38.099999999999994x80x43.1 mm. The ConCentra principle replaces point or eccentric clamping: a stepped sleeve between shaft and inner ring is driven axially to contract uniformly, concentric with the sphered-OD sealed ball insert. the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the three-digit -108 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 8/16 in = 38.1 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 38.099999999999994x80x43.1 mm (1.5x3.15x1.697 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,800 r/min; mass 620 g. Fatigue-limit check: Pu 0.8 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YSP 208-108 SB-2F — most belt-driven mounted-unit loads sit comfortably under 2.606 % of C. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 51.8 mm, d2 62 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Grease-life arithmetic is dominated by speed: at dn approx 2.83x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Static-first planning: the 0.441 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 38.099999999999994 mm shaft, not the 30.7 kN L10 value. Bore-to-OD planning: OD 80 over bore 38.099999999999994 is a 2.1x step, while bore/overall-width gives 0.884; the spherical seat in the matching Y-housing must be specified to the 80 mm OD, not to a cylindrical housing bore. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Sleeve geometry: the ConCentra stepped sleeve occupies the symmetric extension up to the 43.1 mm overall width while the sphered outer ring stays 21 mm wide — uniform sleeve contraction is why run-out stays low at 38.099999999999994 mm bore.", "applications": [ "fan and blower positions sensitive to imbalance", "vibrating conveyors and sieves where screws loosen", "food and packaging conveyors" ], "failure_modes": [ "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "stepped sleeve driven crooked scores the shaft and leaves one clamping arc unloaded", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 38.099999999999994 mm shaft.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 43.1 mm-wide sleeve causes a local unclamped arc that later frets.", "Ordering discipline for the 38.099999999999994 mm size: the chapter lists several executions side by side (YSP2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-208-108-SB-2F?", "a": "YSP 208-108 SB-2F measures 38.099999999999994 mm bore x 80 mm OD x 43.1 mm overall width (outer ring 21 mm wide), 1.5 x 3.15 x 1.697 in; mass about 620 g. SKF 17000 ratings: C 30.7 kN, C0 19 kN, Pu 0.8 kN, limiting speed 4,800 r/min." }, { "q": "What does the designation YSP 208-108 SB-2F mean?", "a": "the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the three-digit -108 tail codes the bore in inches for inch-shaft bearings: 1 whole inch 8/16 in = 38.1 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." }, { "q": "When should I choose YSP over YAR or YEL?", "a": "Choose ConCentra for high run-out accuracy, vibrating or reversing shafts, and shafts that must not be marked: fans, vibrating conveyors, sieves and balanced rotors. It needs the correct sleeve and drive procedure rather than simple screw tightening." } ], "cross_ref": [ { "equiv_sku": "YELAG-208-108", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x43.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YELAG 208-108 is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YEL-208-108-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x43.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YEL 208-108-2F is the eccentric collar locking, both-sides-extended inner ring execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "YSPAG-208-108", "equiv_brand": "SKF", "level": "full", "note": "Same 38.099999999999994x80x43.1 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 208-108 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-208-108-SB-2F", "YSP 208-108 SB-2F" ], "locale_variants": {} }, { "sku": "YSPAG-209-111", "brand": "SKF", "manufacturer_designation": "YSPAG 209-111", "series": "YSP2-series", "type": "insert", "d_mm": 42.8625, "D_mm": 85, "B_mm": 44.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 850, "max_rpm": 850, "weight_g": 690, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSPAG 209-111 is a SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, 42.8625x85x44.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction is a sealed deep-groove insert, a symmetrically extended inner ring and the stepped ConCentra sleeve — uniform grip, minimal run-out, no shaft damage from screw points or an eccentric mass. reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -111 = 42.862 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery. Envelope 42.8625x85x44.2 mm (1.688x3.346x1.74 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 850 r/min; mass 690 g. Mass-to-load ratio for YSPAG-209-111: 20.783 g of catalogue mass per rated kN of C, and 16.098 g per millimetre of bore — useful when comparing executions of the same 42.8625x85 mm envelope on the drawing. Grease-life arithmetic is dominated by speed: at dn approx 0.54x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the AG variant caps speed so aggressively, and high-temperature mounts shorten both even when load is light. The s1 26.7 mm dimension is printed for the locking zone — the pre-drive position of the ConCentra stepped sleeve — and it is verified at mounting, not recoverable from d/D/B alone. Selection figures for YSPAG 209-111: C0/C is 0.651, Pu 0.915 kN is 2.756 % of the 33.2 kN dynamic rating, and the 690 g catalogue mass works out to roughly 16.098 g per millimetre of the 42.8625 mm bore. Imperial procurement cross-check: 1.688 in bore, 3.346 in OD, 1.74 in overall width; the 690 g mass converts to 0.690 kg (24.3 oz) for the bill of materials. Reuse note for YSPAG-209-111: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 42.8625 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "food and packaging conveyors", "vibrating conveyors and sieves where screws loosen", "high-speed textile and processing rollers" ], "failure_modes": [ "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "stepped sleeve driven crooked scores the shaft and leaves one clamping arc unloaded", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 42.8625 mm shaft.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 44.2 mm-wide sleeve causes a local unclamped arc that later frets.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "Catalogue ratings belong to YSPAG 209-111 as the concentra two ag execution; other order numbers of the YSPAG 209-111 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSPAG-209-111?", "a": "The catalogue envelope is 42.8625x85x44.2 mm with a spherical outside surface; mass 690 g. Ratings C 33.2/21.6 kN, Pu 0.915 kN, limiting speed 850 r/min." }, { "q": "What does the designation YSPAG 209-111 mean?", "a": "reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -111 = 42.862 mm, which is why this row sits beside, not on, the metric bore size. AG is the application variant for agricultural equipment — the same bore and OD as the standard sealed size but an application-specific grease/seal build and a conservative limiting speed for field machinery." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." }, { "q": "When should I choose YSP over YAR or YEL?", "a": "Choose ConCentra for high run-out accuracy, vibrating or reversing shafts, and shafts that must not be marked: fans, vibrating conveyors, sieves and balanced rotors. It needs the correct sleeve and drive procedure rather than simple screw tightening." } ], "cross_ref": [ { "equiv_sku": "YSP-209-111-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 42.8625x85x44.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 209-111 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSPAG-209-111", "YSPAG 209-111" ], "locale_variants": {} }, { "sku": "YSP-209-111-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 209-111 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 42.8625, "D_mm": 85, "B_mm": 44.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSP2 series order number YSP 209-111 SB-2F is a SKF insert bearing (Y-bearing) for a 42.8625 mm (1.688 in) shaft: SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 85 mm. Inside is a capped ball insert whose extended inner ring tapers onto a multi-step locking sleeve; the sleeve grips the shaft around its full circumference and the spherical outer ring pivots in the housing. YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. inch bore code -111 decodes as 1\" +11/16, i.e. 42.862 mm; the metric coded size YSP 209 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 42.8625x85x44.2 mm (1.688x3.346x1.74 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 700 g. Bore-to-OD planning: OD 85 over bore 42.8625 is a 1.983x step, while bore/overall-width gives 0.97; the spherical seat in the matching Y-housing must be specified to the 85 mm OD, not to a cylindrical housing bore. Static-first planning: the 0.489 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 42.8625 mm shaft, not the 33.2 kN L10 value. Grease-life arithmetic is dominated by speed: at dn approx 2.75x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Pitch-diameter arithmetic: dm = (42.8625+85)/2 = 63.931 mm; at the 4,300 r/min limiting speed the ball set runs at dn approx 2.75x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Width accounting on this execution: 44.2 mm overall and 22 mm outer-ring width leave the housing designer 22.2 mm of inner-ring projection to accommodate the locking arrangement. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Sleeve geometry: the ConCentra stepped sleeve occupies the symmetric extension up to the 44.2 mm overall width while the sphered outer ring stays 22 mm wide — uniform sleeve contraction is why run-out stays low at 42.8625 mm bore.", "applications": [ "food and packaging conveyors", "high-speed textile and processing rollers", "vibrating conveyors and sieves where screws loosen" ], "failure_modes": [ "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "undersized/over-toleranced shaft never reaches full sleeve grip despite correct drive-up", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 44.2 mm-wide sleeve causes a local unclamped arc that later frets.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 42.8625 mm shaft.", "The 33.2/21.6 kN figures belong specifically to YSP 209-111 SB-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-209-111-SB-2F?", "a": "Boundary dimensions: bore 42.8625 mm, sphered OD 85 mm, overall width 44.2 mm; weight 700 g. Loads: dynamic 33.2 kN, static 21.6 kN, fatigue 0.915 kN; the only published speed is the 4,300 r/min limiting value." }, { "q": "What does the designation YSP 209-111 SB-2F mean?", "a": "YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. inch bore code -111 decodes as 1\" +11/16, i.e. 42.862 mm; the metric coded size YSP 209 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "When should I choose YSP over YAR or YEL?", "a": "Choose ConCentra for high run-out accuracy, vibrating or reversing shafts, and shafts that must not be marked: fans, vibrating conveyors, sieves and balanced rotors. It needs the correct sleeve and drive procedure rather than simple screw tightening." }, { "q": "What does SB mean in YSP 209-111 SB-2F?", "a": "SB identifies the ConCentra ball bearing with a shortened inner ring; the overall width is shorter than the non-SB ConCentra design while keeping the concentric sleeve lock and the -2F seal/flinger package." } ], "cross_ref": [ { "equiv_sku": "YSPAG-209-111", "equiv_brand": "SKF", "level": "full", "note": "Same 42.8625x85x44.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 209-111 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-209-111-SB-2F", "YSP 209-111 SB-2F" ], "locale_variants": {} }, { "sku": "YSPAG-210-115", "brand": "SKF", "manufacturer_designation": "YSPAG 210-115", "series": "YSP2-series", "type": "insert", "d_mm": 49.2125, "D_mm": 90, "B_mm": 46.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 800, "max_rpm": 800, "weight_g": 740, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSP2 series order number YSPAG 210-115 is a SKF insert bearing (Y-bearing) for a 49.2125 mm (1.938 in) shaft: SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 90 mm. Inside is a capped ball insert whose extended inner ring tapers onto a multi-step locking sleeve; the sleeve grips the shaft around its full circumference and the spherical outer ring pivots in the housing. YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. inch bore code -115 decodes as 1\" +15/16, i.e. 49.212 mm; the metric coded size YSPAG 210 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution. Envelope 49.2125x90x46.2 mm (1.938x3.543x1.819 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 800 r/min; mass 740 g. Selection figures for YSPAG 210-115: C0/C is 0.661, Pu 0.98 kN is 2.792 % of the 35.1 kN dynamic rating, and the 740 g catalogue mass works out to roughly 15.037 g per millimetre of the 49.2125 mm bore. Outer-vs-overall width: the outer ring is 22 mm wide inside the 46.2 mm total, so the extended inner ring accounts for 0.524 of the overall width (12.1 mm of axial projection per side). Inner-geometry cross-reference: the catalogue shoulder diameters (d1 62.51 mm, d2 72 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. The s1 27.7 mm dimension is printed for the locking zone — the pre-drive position of the ConCentra stepped sleeve — and it is verified at mounting, not recoverable from d/D/B alone. Capacity density: 35.1 kN from 0.740 kg of bearing steel is about 47.432 kN per kilogram, and per width millimetre the 46.2 mm unit carries 0.76 kN of dynamic capacity. Sleeve geometry: the ConCentra stepped sleeve occupies the symmetric extension up to the 46.2 mm overall width while the sphered outer ring stays 22 mm wide — uniform sleeve contraction is why run-out stays low at 49.2125 mm bore.", "applications": [ "vibrating conveyors and sieves where screws loosen", "fan and blower positions sensitive to imbalance", "high-speed textile and processing rollers" ], "failure_modes": [ "stepped sleeve driven crooked scores the shaft and leaves one clamping arc unloaded", "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 46.2 mm-wide sleeve causes a local unclamped arc that later frets.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 49.2125 mm shaft.", "The 35.1/23.2 kN figures belong specifically to YSPAG 210-115; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSPAG-210-115?", "a": "Boundary dimensions: bore 49.2125 mm, sphered OD 90 mm, overall width 46.2 mm; weight 740 g. Loads: dynamic 35.1 kN, static 23.2 kN, fatigue 0.98 kN; the only published speed is the 800 r/min limiting value." }, { "q": "What does the designation YSPAG 210-115 mean?", "a": "YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. inch bore code -115 decodes as 1\" +15/16, i.e. 49.212 mm; the metric coded size YSPAG 210 shares the same envelope but its bore is the metric value, not this one. the AG suffix identifies the farm-duty variant of the range: sealed and flinger-protected for chaff and dust, with the catalogue deliberately derating its permissible speed versus the industrial execution." }, { "q": "What does SB mean in YSPAG 210-115?", "a": "SB identifies the ConCentra ball bearing with a shortened inner ring; the overall width is shorter than the non-SB ConCentra design while keeping the concentric sleeve lock and the -2F seal/flinger package." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." } ], "cross_ref": [ { "equiv_sku": "YSP-210-115-SB-2F", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x46.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSP 210-115 SB-2F is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSPAG-210-115", "YSPAG 210-115" ], "locale_variants": {} }, { "sku": "YSP-210-115-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 210-115 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 49.2125, "D_mm": 90, "B_mm": 46.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 760, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSP 210-115 SB-2F is a SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, 49.2125x90x46.2 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction is a sealed deep-groove insert, a symmetrically extended inner ring and the stepped ConCentra sleeve — uniform grip, minimal run-out, no shaft damage from screw points or an eccentric mass. reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -115 = 49.212 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 49.2125x90x46.2 mm (1.938x3.543x1.819 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,000 r/min; mass 760 g. Grease-life arithmetic is dominated by speed: at dn approx 2.78x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Fillet discipline: the printed minimum-fillet limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 49.2125x90 mm insert on its chamfer tilts the whole spherical seat. Load balance for documentation: C0 23.2 kN against C 35.1 kN gives a 0.661 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Mass-to-load ratio for YSP-210-115-SB-2F: 21.652 g of catalogue mass per rated kN of C, and 15.443 g per millimetre of bore — useful when comparing executions of the same 49.2125x90 mm envelope on the drawing. Selection figures for YSP 210-115 SB-2F: C0/C is 0.661, Pu 0.98 kN is 2.792 % of the 35.1 kN dynamic rating, and the 760 g catalogue mass works out to roughly 15.443 g per millimetre of the 49.2125 mm bore. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Reuse note for YSP-210-115-SB-2F: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 49.2125 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "fan and blower positions sensitive to imbalance", "food and packaging conveyors", "vibrating conveyors and sieves where screws loosen" ], "failure_modes": [ "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 49.2125 mm shaft.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 46.2 mm-wide sleeve causes a local unclamped arc that later frets.", "Ordering discipline for the 49.2125 mm size: the chapter lists several executions side by side (YSP2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-210-115-SB-2F?", "a": "The catalogue envelope is 49.2125x90x46.2 mm with a spherical outside surface; mass 760 g. Ratings C 35.1/23.2 kN, Pu 0.98 kN, limiting speed 4,000 r/min." }, { "q": "What does the designation YSP 210-115 SB-2F mean?", "a": "reading YSP: SKF ConCentra technology locks the shaft through a stepped sleeve that contracts uniformly, chosen for high run-out accuracy and for shafts that must not be marked by screw points or an eccentric. for inch shafts the order number carries the bore as whole-inches plus sixteenths: -115 = 49.212 mm, which is why this row sits beside, not on, the metric bore size. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." } ], "cross_ref": [ { "equiv_sku": "YSPAG-210-115", "equiv_brand": "SKF", "level": "full", "note": "Same 49.2125x90x46.2 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSPAG 210-115 is the SKF ConCentra stepped-sleeve locking execution of this size — boundary dimensions interchangeable, locking/seal execution differs." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-210-115-SB-2F", "YSP 210-115 SB-2F" ], "locale_variants": {} }, { "sku": "YSP-211-200-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 211-200 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 50.8, "D_mm": 100, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 1100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSP2 series order number YSP 211-200 SB-2F is a SKF insert bearing (Y-bearing) for a 50.8 mm (2 in) shaft: SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 100 mm. Inside is a capped ball insert whose extended inner ring tapers onto a multi-step locking sleeve; the sleeve grips the shaft around its full circumference and the spherical outer ring pivots in the housing. YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. inch bore code -200 decodes as 2\", i.e. 50.8 mm; the metric coded size YSP 211 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 50.8x100x49.2 mm (2x3.937x1.937 in), outer ring 25 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,600 r/min; mass 1100 g. Fatigue-limit check: Pu 1.25 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YSP 211-200 SB-2F — most belt-driven mounted-unit loads sit comfortably under 2.867 % of C. Bore-to-OD planning: OD 100 over bore 50.8 is a 1.969x step, while bore/overall-width gives 1.033; the spherical seat in the matching Y-housing must be specified to the 100 mm OD, not to a cylindrical housing bore. Load balance for documentation: C0 29 kN against C 43.6 kN gives a 0.665 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. The s1 29.2 mm dimension is printed for the locking zone — the pre-drive position of the ConCentra stepped sleeve — and it is verified at mounting, not recoverable from d/D/B alone. Pitch-diameter arithmetic: dm = (50.8+100)/2 = 75.4 mm; at the 3,600 r/min limiting speed the ball set runs at dn approx 2.71x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Reuse note for YSP-211-200-SB-2F: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 50.8 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "fan and blower positions sensitive to imbalance", "food and packaging conveyors", "vibrating conveyors and sieves where screws loosen" ], "failure_modes": [ "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 49.2 mm-wide sleeve causes a local unclamped arc that later frets.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 50.8 mm shaft.", "The 43.6/29 kN figures belong specifically to YSP 211-200 SB-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-211-200-SB-2F?", "a": "Boundary dimensions: bore 50.8 mm, sphered OD 100 mm, overall width 49.2 mm; weight 1100 g. Loads: dynamic 43.6 kN, static 29 kN, fatigue 1.25 kN; the only published speed is the 3,600 r/min limiting value." }, { "q": "What does the designation YSP 211-200 SB-2F mean?", "a": "YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. inch bore code -200 decodes as 2\", i.e. 50.8 mm; the metric coded size YSP 211 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." } ], "cross_ref": [ { "equiv_sku": "YSP", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-211-200-SB-2F", "YSP 211-200 SB-2F" ], "locale_variants": {} }, { "sku": "YSP-211-203-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 211-203 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 55.5625, "D_mm": 100, "B_mm": 49.2, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 970, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSP 211-203 SB-2F is SKF's 55.5625 mm-bore SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring in the YSP2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 55.5625x100x49.2 mm. The ConCentra principle replaces point or eccentric clamping: a stepped sleeve between shaft and inner ring is driven axially to contract uniformly, concentric with the sphered-OD sealed ball insert. the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the three-digit -203 tail codes the bore in inches for inch-shaft bearings: 2 whole inch 3/16 in = 55.563 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 55.5625x100x49.2 mm (2.188x3.937x1.937 in), outer ring 25 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,600 r/min; mass 970 g. Bore-to-OD planning: OD 100 over bore 55.5625 is a 1.8x step, while bore/overall-width gives 1.129; the spherical seat in the matching Y-housing must be specified to the 100 mm OD, not to a cylindrical housing bore. Capacity density: 43.6 kN from 0.970 kg of bearing steel is about 44.948 kN per kilogram, and per width millimetre the 49.2 mm unit carries 0.886 kN of dynamic capacity. Fillet discipline: the printed minimum-fillet limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 55.5625x100 mm insert on its chamfer tilts the whole spherical seat. Grease-life arithmetic is dominated by speed: at dn approx 2.80x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Speed ceiling of 3,600 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Reuse note for YSP-211-203-SB-2F: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 55.5625 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "heavily vibrating screen and feeder shafts", "large fan positions with dynamic balancing requirements", "process-industry roller beds" ], "failure_modes": [ "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 55.5625 mm shaft.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 49.2 mm-wide sleeve causes a local unclamped arc that later frets.", "Catalogue ratings belong to YSP 211-203 SB-2F as the concentra two f execution; other order numbers of the YSP 211-203 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-211-203-SB-2F?", "a": "YSP 211-203 SB-2F measures 55.5625 mm bore x 100 mm OD x 49.2 mm overall width (outer ring 25 mm wide), 2.188 x 3.937 x 1.937 in; mass about 970 g. SKF 17000 ratings: C 43.6 kN, C0 29 kN, Pu 1.25 kN, limiting speed 3,600 r/min." }, { "q": "What does the designation YSP 211-203 SB-2F mean?", "a": "the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the three-digit -203 tail codes the bore in inches for inch-shaft bearings: 2 whole inch 3/16 in = 55.563 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "What does SB mean in YSP 211-203 SB-2F?", "a": "SB identifies the ConCentra ball bearing with a shortened inner ring; the overall width is shorter than the non-SB ConCentra design while keeping the concentric sleeve lock and the -2F seal/flinger package." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." } ], "cross_ref": [ { "equiv_sku": "YSP", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-211-203-SB-2F", "YSP 211-203 SB-2F" ], "locale_variants": {} }, { "sku": "YSP-212-204-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 212-204 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 57.15, "D_mm": 110, "B_mm": 51.7, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 36, "fatigue_load_limit_kN": 1.53, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSP2 series order number YSP 212-204 SB-2F is a SKF insert bearing (Y-bearing) for a 57.15 mm (2.25 in) shaft: SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 110 mm. Inside is a capped ball insert whose extended inner ring tapers onto a multi-step locking sleeve; the sleeve grips the shaft around its full circumference and the spherical outer ring pivots in the housing. YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. inch bore code -204 decodes as 2\" +4/16, i.e. 57.15 mm; the metric coded size YSP 212 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 57.15x110x51.7 mm (2.25x4.331x2.035 in), outer ring 26 mm wide, C 52.7 kN, C0 36 kN, Pu 1.53 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,400 r/min; mass 1350 g. Spherical-seat note in numbers: the 110 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 83.575 = 262.559 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Speed ceiling of 3,400 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Load balance for documentation: C0 36 kN against C 52.7 kN gives a 0.683 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Mass-to-load ratio for YSP-212-204-SB-2F: 25.617 g of catalogue mass per rated kN of C, and 23.622 g per millimetre of bore — useful when comparing executions of the same 57.15x110 mm envelope on the drawing. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 75.64 mm, d2 83 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Reuse note for YSP-212-204-SB-2F: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 57.15 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "large fan positions with dynamic balancing requirements", "heavily vibrating screen and feeder shafts", "process-industry roller beds" ], "failure_modes": [ "undersized/over-toleranced shaft never reaches full sleeve grip despite correct drive-up", "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 51.7 mm-wide sleeve causes a local unclamped arc that later frets.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 57.15 mm shaft.", "Ordering discipline for the 57.15 mm size: the chapter lists several executions side by side (YSP2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-212-204-SB-2F?", "a": "Boundary dimensions: bore 57.15 mm, sphered OD 110 mm, overall width 51.7 mm; weight 1350 g. Loads: dynamic 52.7 kN, static 36 kN, fatigue 1.53 kN; the only published speed is the 3,400 r/min limiting value." }, { "q": "What does the designation YSP 212-204 SB-2F mean?", "a": "YSP denotes the ConCentra design — the SB execution in this chapter has the shortened inner ring; axial driving of the stepped sleeve produces a near-true concentric clamp with virtually no run-out penalty. inch bore code -204 decodes as 2\" +4/16, i.e. 57.15 mm; the metric coded size YSP 212 shares the same envelope but its bore is the metric value, not this one. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "What does SB mean in YSP 212-204 SB-2F?", "a": "SB identifies the ConCentra ball bearing with a shortened inner ring; the overall width is shorter than the non-SB ConCentra design while keeping the concentric sleeve lock and the -2F seal/flinger package." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." } ], "cross_ref": [ { "equiv_sku": "YSP", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-212-204-SB-2F", "YSP 212-204 SB-2F" ], "locale_variants": {} }, { "sku": "YSP-212-207-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 212-207 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 61.912499999999994, "D_mm": 110, "B_mm": 51.7, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 36, "fatigue_load_limit_kN": 1.53, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSP 212-207 SB-2F is SKF's 61.912499999999994 mm-bore SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring in the YSP2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 61.912499999999994x110x51.7 mm. The ConCentra principle replaces point or eccentric clamping: a stepped sleeve between shaft and inner ring is driven axially to contract uniformly, concentric with the sphered-OD sealed ball insert. the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the three-digit -207 tail codes the bore in inches for inch-shaft bearings: 2 whole inch 7/16 in = 61.912 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 61.912499999999994x110x51.7 mm (2.438x4.331x2.035 in), outer ring 26 mm wide, C 52.7 kN, C0 36 kN, Pu 1.53 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,400 r/min; mass 1200 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 75.64 mm, d2 87.6 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Envelope arithmetic: the radial section from 61.912499999999994 mm bore to 110 mm OD is 24.044 mm; dividing C 52.7 kN by that section gives 2.192 kN per section millimetre, and the 51.7 mm overall width is 2.15x the section. The s1 30.5 mm dimension is printed for the locking zone — the pre-drive position of the ConCentra stepped sleeve — and it is verified at mounting, not recoverable from d/D/B alone. Pitch-diameter arithmetic: dm = (61.912499999999994+110)/2 = 85.956 mm; at the 3,400 r/min limiting speed the ball set runs at dn approx 2.92x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Width accounting on this execution: 51.7 mm overall and 26 mm outer-ring width leave the housing designer 25.7 mm of inner-ring projection to accommodate the locking arrangement. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Reuse note for YSP-212-207-SB-2F: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 61.912499999999994 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "process-industry roller beds", "large fan positions with dynamic balancing requirements", "heavily vibrating screen and feeder shafts" ], "failure_modes": [ "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 61.912499999999994 mm shaft.", "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 51.7 mm-wide sleeve causes a local unclamped arc that later frets.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "Catalogue ratings belong to YSP 212-207 SB-2F as the concentra two f execution; other order numbers of the YSP 212-207 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-212-207-SB-2F?", "a": "YSP 212-207 SB-2F measures 61.912499999999994 mm bore x 110 mm OD x 51.7 mm overall width (outer ring 26 mm wide), 2.438 x 4.331 x 2.035 in; mass about 1200 g. SKF 17000 ratings: C 52.7 kN, C0 36 kN, Pu 1.53 kN, limiting speed 3,400 r/min." }, { "q": "What does the designation YSP 212-207 SB-2F mean?", "a": "the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the three-digit -207 tail codes the bore in inches for inch-shaft bearings: 2 whole inch 7/16 in = 61.912 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." } ], "cross_ref": [ { "equiv_sku": "YSP", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-212-207-SB-2F", "YSP 212-207 SB-2F" ], "locale_variants": {} }, { "sku": "YSP-213-211-SB-2F", "brand": "SKF", "manufacturer_designation": "YSP 213-211 SB-2F", "series": "YSP2-series", "type": "insert", "d_mm": 68.2625, "D_mm": 120, "B_mm": 52.7, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 57.2, "static_load_kN": 40, "fatigue_load_limit_kN": 1.7, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSP 213-211 SB-2F is SKF's 68.2625 mm-bore SKF ConCentra insert bearing with concentric stepped-sleeve locking and symmetrically extended inner ring in the YSP2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 68.2625x120x52.7 mm. The ConCentra principle replaces point or eccentric clamping: a stepped sleeve between shaft and inner ring is driven axially to contract uniformly, concentric with the sphered-OD sealed ball insert. the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the three-digit -211 tail codes the bore in inches for inch-shaft bearings: 2 whole inch 11/16 in = 68.263 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 68.2625x120x52.7 mm (2.688x4.724x2.075 in), outer ring 27 mm wide, C 57.2 kN, C0 40 kN, Pu 1.7 kN. The catalogue publishes a single speed ceiling, the limiting speed: 3,000 r/min; mass 1400 g. At the printed limiting speed of 3,000 r/min the mean diameter dm = 94.131 mm implies dn about 2.82x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Bore-to-OD planning: OD 120 over bore 68.2625 is a 1.758x step, while bore/overall-width gives 1.295; the spherical seat in the matching Y-housing must be specified to the 120 mm OD, not to a cylindrical housing bore. The s1 31 mm dimension is printed for the locking zone — the pre-drive position of the ConCentra stepped sleeve — and it is verified at mounting, not recoverable from d/D/B alone. Static-first planning: the 0.759 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 68.2625 mm shaft, not the 57.2 kN L10 value. Envelope arithmetic: the radial section from 68.2625 mm bore to 120 mm OD is 25.869 mm; dividing C 57.2 kN by that section gives 2.211 kN per section millimetre, and the 52.7 mm overall width is 2.037x the section. ConCentra mounting note: the SB shortened-inner-ring sleeve is driven AXIALLY with the proper sleeve/drift until it seats against the abutment — driving at an angle burrs the stepped sleeve and destroys the concentricity advantage; removal needs the matching withdrawal technique, never a puller on the flingers. Reuse note for YSP-213-211-SB-2F: the stepped locking sleeve is a one-time clamping component in most over-torque cases; if the 68.2625 mm shaft shows a polished sleeve imprint after withdrawal, fit a new sleeve rather than re-driving the old one.", "applications": [ "process-industry roller beds", "large fan positions with dynamic balancing requirements", "heavily vibrating screen and feeder shafts" ], "failure_modes": [ "puller applied to the sealed outer side during removal destroys flingers and seals instead of releasing the sleeve", "sleeve re-driven after a first seating without cleaning gives false drive-up and creep under load", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Inspect the shaft before sleeve mounting: a single deep keyway burr or old screw-point dimple under the 52.7 mm-wide sleeve causes a local unclamped arc that later frets.", "The SB shortened-inner-ring ConCentra unit needs its matching mounting sleeve and procedure; substituting a standard YSP sleeve or a generic drift is the usual cause of crooked drive-up on the 68.2625 mm shaft.", "ConCentra solves run-out and fretting but not gross misalignment — the housing spherical seat still carries that function; do not use the sleeve grip as an excuse to skip housing alignment.", "The 57.2/40 kN figures belong specifically to YSP 213-211 SB-2F; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSP-213-211-SB-2F?", "a": "YSP 213-211 SB-2F measures 68.2625 mm bore x 120 mm OD x 52.7 mm overall width (outer ring 27 mm wide), 2.688 x 4.724 x 2.075 in; mass about 1400 g. SKF 17000 ratings: C 57.2 kN, C0 40 kN, Pu 1.7 kN, limiting speed 3,000 r/min." }, { "q": "What does the designation YSP 213-211 SB-2F mean?", "a": "the YSP prefix names SKF ConCentra locking: a stepped (multi-diameter) sleeve between shaft and inner ring is driven axially to grip concentrically, avoiding the local shaft fretting of set screws or the imbalance of an eccentric collar. the three-digit -211 tail codes the bore in inches for inch-shaft bearings: 2 whole inch 11/16 in = 68.263 mm (first digit whole inches, next two sixteenths of an inch). suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "What is SKF ConCentra locking?", "a": "A stepped (multi-diameter) sleeve between the shaft and the tapered/stepped inner-ring seat is driven axially until it contracts uniformly around the shaft — full-circumference grip, low run-out and no screw-point indentations or eccentric imbalance." }, { "q": "Can the locking sleeve be reused?", "a": "Usually not after a full service life or an over-torqued first mounting: the stepped sleeve takes a permanent set. SKF recommends a new sleeve whenever the bearing is replaced on the same shaft." } ], "cross_ref": [ { "equiv_sku": "YSP", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSP-213-211-SB-2F", "YSP 213-211 SB-2F" ], "locale_variants": {} }, { "sku": "YSA-205-2FK-H-2305", "brand": "SKF", "manufacturer_designation": "YSA 205-2FK H 2305", "series": "YSA2-series", "type": "insert", "d_mm": 20, "D_mm": 52, "B_mm": 24, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSA 205-2FK H 2305 is a tapered-bore (1:12) insert bearing supplied on its H 2305 adapter sleeve, 20x52x24 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction combines capped deep-groove geometry, a tapered inner-ring bore and the supplied adapter sleeve with locknut seating — factory-grade concentricity on plain drawn shafting. YSA is the adapter-sleeve member of the Y range — tapered bore plus the H 2305 sleeve converts a plain commercial shaft into a precisely located, demountable seat at 20 mm. adapter mounting means the effective bore is the sleeve bore: H 2305 gives the 20 mm shaft fit with no machined shoulder required. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 20x52x24 mm (0.787x2.047x0.945 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. Mounted width B1 35 mm includes the adapter sleeve. Supplied/specified with H 2305. The catalogue publishes a single speed ceiling, the limiting speed: 7,000 r/min; mass 250 g. Grease-life arithmetic is dominated by speed: at dn approx 2.52x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Imperial procurement cross-check: 0.787 in bore, 2.047 in OD, 0.945 in overall width; the 250 g mass converts to 0.250 kg (8.8 oz) for the bill of materials. Fillet discipline: the printed minimum-fillet limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 20x52 mm insert on its chamfer tilts the whole spherical seat. The s1 20.5 mm dimension is printed for the locking zone — the distance before the adapter sleeve is driven up the taper — and it is verified at mounting, not recoverable from d/D/B alone. At the printed limiting speed of 7,000 r/min the mean diameter dm = 36 mm implies dn about 2.52x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Mounting sequence for YSA-205-2FK-H-2305: slide H 2305 on first, seat the bearing in the housing register, then draw the nut to drive-up — reversing the order (sleeve fully tightened before housing engagement) locks in misalignment the sphered seat cannot cure.", "applications": [ "light transmission shafts without shoulders", "small fans on plain drawn shafts" ], "failure_modes": [ "locknut not secured (no tab or thread locking): the sleeve unwinds under vibration and the unit collapses axially", "shaft shoulder absent or too small: the sleeve pulls through the bore instead of reacting the drive-up", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "The order number is incomplete without the sleeve: YSA-205-2FK-H-2305 specifies the H 2305 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "Sleeve drive-up uses the printed s1 20.5 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "Catalogue ratings belong to YSA 205-2FK H 2305 as the adapter two f execution; other order numbers of the YSA 205-2FK size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-205-2FK-H-2305?", "a": "The catalogue envelope is 20x52x24 mm with a spherical outside surface; mass 250 g. Ratings C 14/7.8 kN, Pu 0.335 kN, limiting speed 7,000 r/min." }, { "q": "What does the designation YSA 205-2FK H 2305 mean?", "a": "YSA is the adapter-sleeve member of the Y range — tapered bore plus the H 2305 sleeve converts a plain commercial shaft into a precisely located, demountable seat at 20 mm. adapter mounting means the effective bore is the sleeve bore: H 2305 gives the 20 mm shaft fit with no machined shoulder required. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (20.5 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." }, { "q": "What is the difference between H, HA and HE sleeves?", "a": "H sleeves fit metric shafts while HA/HE cover inch-shaft sizes of the same tapered insert; the sleeve designation, not the bearing code, determines the actual shaft diameter — always specify the bearing AND sleeve together." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-205-2FK-H-2305", "YSA 205-2FK H 2305" ], "locale_variants": {} }, { "sku": "YSA-206-2FK-H-2306", "brand": "SKF", "manufacturer_designation": "YSA 206-2FK H 2306", "series": "YSA2-series", "type": "insert", "d_mm": 25, "D_mm": 62, "B_mm": 28, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 380, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSA 206-2FK H 2306 is SKF's 25 mm-bore tapered-bore (1:12) insert bearing supplied on its H 2306 adapter sleeve in the YSA2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 25x62x28 mm. The inner ring carries a 1:12 tapered bore and mounts on the specified adapter sleeve: tightening the sleeve nut draws the ring home on a plain shaft, while the sphered outer ring pivots in the Y-housing. YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the H 2306 sleeve is drawn up the taper to clamp a plain 25 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the H 2306 adapter sleeve, not by the bearing code: the sleeve seats a 25 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 25x62x28 mm (0.984x2.441x1.102 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. Mounted width B1 38 mm includes the adapter sleeve. Supplied/specified with H 2306. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 380 g. Static-first planning: the 0.4 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 25 mm shaft, not the 19.5 kN L10 value. Bore-to-OD planning: OD 62 over bore 25 is a 2.48x step, while bore/overall-width gives 0.893; the spherical seat in the matching Y-housing must be specified to the 62 mm OD, not to a cylindrical housing bore. Rating split for the maintenance file: dynamic 19.5 kN (L10), static 11.2 kN (s0 shock check), fatigue 0.475 kN (adjusted life) — three separate uses for YSA 206-2FK H 2306, none interchangeable with another. Envelope arithmetic: the radial section from 25 mm bore to 62 mm OD is 18.5 mm; dividing C 19.5 kN by that section gives 1.054 kN per section millimetre, and the 28 mm overall width is 1.514x the section. The s1 22.5 mm dimension is printed for the locking zone — the distance before the adapter sleeve is driven up the taper — and it is verified at mounting, not recoverable from d/D/B alone. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Sleeve geometry on YSA-206-2FK-H-2306: H 2306 pulls the tapered inner ring onto the 25 mm plain shaft; the printed s1 22.5 mm is the pre-drive distance and 38 mm is the overall width including the sleeve hardware.", "applications": [ "fan and blower shafts of plain commercial steel", "ventilation equipment with long through-shafts", "general transmission arrangements on h6 plain shafts" ], "failure_modes": [ "shaft shoulder absent or too small: the sleeve pulls through the bore instead of reacting the drive-up", "sleeve over-tightened: internal clearance vanishes and the bearing runs hot from the first hours", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Sleeve drive-up uses the printed s1 22.5 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "The order number is incomplete without the sleeve: YSA-206-2FK-H-2306 specifies the H 2306 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "The 19.5/11.2 kN figures belong specifically to YSA 206-2FK H 2306; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-206-2FK-H-2306?", "a": "YSA 206-2FK H 2306 measures 25 mm bore x 62 mm OD x 28 mm overall width (outer ring 18 mm wide), 0.984 x 2.441 x 1.102 in; mass about 380 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YSA 206-2FK H 2306 mean?", "a": "YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the H 2306 sleeve is drawn up the taper to clamp a plain 25 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the H 2306 adapter sleeve, not by the bearing code: the sleeve seats a 25 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "Why is the bore tapered and what is the H 2306 sleeve?", "a": "The inner ring has a 1:12 tapered bore (K); the H 2306 adapter sleeve is drawn between taper and a plain 25 mm shaft by a locknut, giving a precise, demountable concentric seat without shaft shoulders." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." } ], "cross_ref": [ { "equiv_sku": "YSA-206-2FK-HE-2306", "equiv_brand": "SKF", "level": "full", "note": "Same 25x62x28 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSA 206-2FK HE 2306 is the tapered bore on HE 2306 adapter sleeve execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25 mm vs 25.4 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-206-2FK-H-2306", "YSA 206-2FK H 2306" ], "locale_variants": {} }, { "sku": "YSA-207-2FK-H-2307", "brand": "SKF", "manufacturer_designation": "YSA 207-2FK H 2307", "series": "YSA2-series", "type": "insert", "d_mm": 30, "D_mm": 72, "B_mm": 30.5, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 540, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSA 207-2FK H 2307 is SKF's 30 mm-bore tapered-bore (1:12) insert bearing supplied on its H 2307 adapter sleeve in the YSA2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 30x72x30.5 mm. The inner ring carries a 1:12 tapered bore and mounts on the specified adapter sleeve: tightening the sleeve nut draws the ring home on a plain shaft, while the sphered outer ring pivots in the Y-housing. YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the H 2307 sleeve is drawn up the taper to clamp a plain 30 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the H 2307 adapter sleeve, not by the bearing code: the sleeve seats a 30 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 30x72x30.5 mm (1.181x2.835x1.201 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 43 mm includes the adapter sleeve. Supplied/specified with H 2307. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 540 g. Outer-vs-overall width: the outer ring is 19 mm wide inside the 30.5 mm total, so the extended inner ring accounts for 0.377 of the overall width (5.75 mm of axial projection per side). Static-first planning: the 0.502 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 30 mm shaft, not the 25.5 kN L10 value. The s1 24.8 mm dimension is printed for the locking zone — the distance before the adapter sleeve is driven up the taper — and it is verified at mounting, not recoverable from d/D/B alone. Load balance for documentation: C0 15.3 kN against C 25.5 kN gives a 0.6 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Rating split for the maintenance file: dynamic 25.5 kN (L10), static 15.3 kN (s0 shock check), fatigue 0.655 kN (adjusted life) — three separate uses for YSA 207-2FK H 2307, none interchangeable with another. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Mounting sequence for YSA-207-2FK-H-2307: slide H 2307 on first, seat the bearing in the housing register, then draw the nut to drive-up — reversing the order (sleeve fully tightened before housing engagement) locks in misalignment the sphered seat cannot cure.", "applications": [ "conveyor positions needing easy removal without shaft damage", "fan and blower shafts of plain commercial steel", "general transmission arrangements on h6 plain shafts" ], "failure_modes": [ "sleeve under-tightened: the tapered inner ring creeps on the sleeve and polishes the taper bright", "shaft shoulder absent or too small: the sleeve pulls through the bore instead of reacting the drive-up", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "Sleeve drive-up uses the printed s1 24.8 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "The order number is incomplete without the sleeve: YSA-207-2FK-H-2307 specifies the H 2307 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Ordering discipline for the 30 mm size: the chapter lists several executions side by side (YSA2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-207-2FK-H-2307?", "a": "YSA 207-2FK H 2307 measures 30 mm bore x 72 mm OD x 30.5 mm overall width (outer ring 19 mm wide), 1.181 x 2.835 x 1.201 in; mass about 540 g. SKF 17000 ratings: C 25.5 kN, C0 15.3 kN, Pu 0.655 kN, limiting speed 5,300 r/min." }, { "q": "What does the designation YSA 207-2FK H 2307 mean?", "a": "YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the H 2307 sleeve is drawn up the taper to clamp a plain 30 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the H 2307 adapter sleeve, not by the bearing code: the sleeve seats a 30 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (24.8 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." }, { "q": "What is the difference between H, HA and HE sleeves?", "a": "H sleeves fit metric shafts while HA/HE cover inch-shaft sizes of the same tapered insert; the sleeve designation, not the bearing code, determines the actual shaft diameter — always specify the bearing AND sleeve together." } ], "cross_ref": [ { "equiv_sku": "YSA-207-2FK-HA-2307", "equiv_brand": "SKF", "level": "full", "note": "Same 30x72x30.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSA 207-2FK HA 2307 is the tapered bore on HA 2307 adapter sleeve execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30 mm vs 30.15 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-207-2FK-H-2307", "YSA 207-2FK H 2307" ], "locale_variants": {} }, { "sku": "YSA-208-2FK-H-2308", "brand": "SKF", "manufacturer_designation": "YSA 208-2FK H 2308", "series": "YSA2-series", "type": "insert", "d_mm": 35, "D_mm": 80, "B_mm": 33.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 710, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSA 208-2FK H 2308 is SKF's 35 mm-bore tapered-bore (1:12) insert bearing supplied on its H 2308 adapter sleeve in the YSA2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 35x80x33.9 mm. The inner ring carries a 1:12 tapered bore and mounts on the specified adapter sleeve: tightening the sleeve nut draws the ring home on a plain shaft, while the sphered outer ring pivots in the Y-housing. YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the H 2308 sleeve is drawn up the taper to clamp a plain 35 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the H 2308 adapter sleeve, not by the bearing code: the sleeve seats a 35 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 35x80x33.9 mm (1.378x3.15x1.335 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. Mounted width B1 46 mm includes the adapter sleeve. Supplied/specified with H 2308. The catalogue publishes a single speed ceiling, the limiting speed: 4,800 r/min; mass 710 g. Bore-to-OD planning: OD 80 over bore 35 is a 2.286x step, while bore/overall-width gives 1.032; the spherical seat in the matching Y-housing must be specified to the 80 mm OD, not to a cylindrical housing bore. Envelope arithmetic: the radial section from 35 mm bore to 80 mm OD is 22.5 mm; dividing C 30.7 kN by that section gives 1.364 kN per section millimetre, and the 33.9 mm overall width is 1.507x the section. Speed ceiling of 4,800 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Static-first planning: the 0.56 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 35 mm shaft, not the 30.7 kN L10 value. Grease-life arithmetic is dominated by speed: at dn approx 2.76x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Sleeve geometry on YSA-208-2FK-H-2308: H 2308 pulls the tapered inner ring onto the 35 mm plain shaft; the printed s1 27.5 mm is the pre-drive distance and 46 mm is the overall width including the sleeve hardware.", "applications": [ "ventilation equipment with long through-shafts", "conveyor positions needing easy removal without shaft damage", "fan and blower shafts of plain commercial steel" ], "failure_modes": [ "sleeve over-tightened: internal clearance vanishes and the bearing runs hot from the first hours", "sleeve under-tightened: the tapered inner ring creeps on the sleeve and polishes the taper bright", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "Sleeve drive-up uses the printed s1 27.5 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "The order number is incomplete without the sleeve: YSA-208-2FK-H-2308 specifies the H 2308 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Ordering discipline for the 35 mm size: the chapter lists several executions side by side (YSA2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-208-2FK-H-2308?", "a": "YSA 208-2FK H 2308 measures 35 mm bore x 80 mm OD x 33.9 mm overall width (outer ring 21 mm wide), 1.378 x 3.15 x 1.335 in; mass about 710 g. SKF 17000 ratings: C 30.7 kN, C0 19 kN, Pu 0.8 kN, limiting speed 4,800 r/min." }, { "q": "What does the designation YSA 208-2FK H 2308 mean?", "a": "YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the H 2308 sleeve is drawn up the taper to clamp a plain 35 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the H 2308 adapter sleeve, not by the bearing code: the sleeve seats a 35 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "Why is the bore tapered and what is the H 2308 sleeve?", "a": "The inner ring has a 1:12 tapered bore (K); the H 2308 adapter sleeve is drawn between taper and a plain 35 mm shaft by a locknut, giving a precise, demountable concentric seat without shaft shoulders." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-208-2FK-H-2308", "YSA 208-2FK H 2308" ], "locale_variants": {} }, { "sku": "YSA-209-2FK-H-2309", "brand": "SKF", "manufacturer_designation": "YSA 209-2FK H 2309", "series": "YSA2-series", "type": "insert", "d_mm": 40, "D_mm": 85, "B_mm": 35, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 840, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSA 209-2FK H 2309 is a tapered-bore (1:12) insert bearing supplied on its H 2309 adapter sleeve, 40x85x35 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction combines capped deep-groove geometry, a tapered inner-ring bore and the supplied adapter sleeve with locknut seating — factory-grade concentricity on plain drawn shafting. YSA is the adapter-sleeve member of the Y range — tapered bore plus the H 2309 sleeve converts a plain commercial shaft into a precisely located, demountable seat at 40 mm. adapter mounting means the effective bore is the sleeve bore: H 2309 gives the 40 mm shaft fit with no machined shoulder required. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 40x85x35 mm (1.575x3.346x1.378 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. Mounted width B1 50 mm includes the adapter sleeve. Supplied/specified with H 2309. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 840 g. Rating split for the maintenance file: dynamic 33.2 kN (L10), static 21.6 kN (s0 shock check), fatigue 0.915 kN (adjusted life) — three separate uses for YSA 209-2FK H 2309, none interchangeable with another. Imperial procurement cross-check: 1.575 in bore, 3.346 in OD, 1.378 in overall width; the 840 g mass converts to 0.840 kg (29.6 oz) for the bill of materials. Fillet discipline: the printed minimum-fillet limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 40x85 mm insert on its chamfer tilts the whole spherical seat. The s1 29 mm dimension is printed for the locking zone — the distance before the adapter sleeve is driven up the taper — and it is verified at mounting, not recoverable from d/D/B alone. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 56.8 mm, d3 65 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Mounting sequence for YSA-209-2FK-H-2309: slide H 2309 on first, seat the bearing in the housing register, then draw the nut to drive-up — reversing the order (sleeve fully tightened before housing engagement) locks in misalignment the sphered seat cannot cure.", "applications": [ "general transmission arrangements on h6 plain shafts", "fan and blower shafts of plain commercial steel", "ventilation equipment with long through-shafts" ], "failure_modes": [ "locknut not secured (no tab or thread locking): the sleeve unwinds under vibration and the unit collapses axially", "shaft shoulder absent or too small: the sleeve pulls through the bore instead of reacting the drive-up", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Sleeve drive-up uses the printed s1 29 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "The order number is incomplete without the sleeve: YSA-209-2FK-H-2309 specifies the H 2309 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "The 33.2/21.6 kN figures belong specifically to YSA 209-2FK H 2309; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-209-2FK-H-2309?", "a": "The catalogue envelope is 40x85x35 mm with a spherical outside surface; mass 840 g. Ratings C 33.2/21.6 kN, Pu 0.915 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YSA 209-2FK H 2309 mean?", "a": "YSA is the adapter-sleeve member of the Y range — tapered bore plus the H 2309 sleeve converts a plain commercial shaft into a precisely located, demountable seat at 40 mm. adapter mounting means the effective bore is the sleeve bore: H 2309 gives the 40 mm shaft fit with no machined shoulder required. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (29 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." }, { "q": "What is the difference between H, HA and HE sleeves?", "a": "H sleeves fit metric shafts while HA/HE cover inch-shaft sizes of the same tapered insert; the sleeve designation, not the bearing code, determines the actual shaft diameter — always specify the bearing AND sleeve together." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-209-2FK-H-2309", "YSA 209-2FK H 2309" ], "locale_variants": {} }, { "sku": "YSA-210-2FK-H-2310", "brand": "SKF", "manufacturer_designation": "YSA 210-2FK H 2310", "series": "YSA2-series", "type": "insert", "d_mm": 45, "D_mm": 90, "B_mm": 37, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 970, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSA2 series order number YSA 210-2FK H 2310 is a SKF insert bearing (Y-bearing) for a 45 mm shaft: tapered-bore (1:12) insert bearing supplied on its H 2310 adapter sleeve, built to the ISO 15 diameter-series envelope with a sphered OD of 90 mm. Inside is a sealed, symmetrically extended ball insert with a tapered bore, the adapter sleeve converting a plain commercial shaft into a precision seat without shoulders, screw points or collars. reading YSA: the inner-ring bore is tapered 1:12 and the bearing ships/specifies with its H 2310 adapter sleeve; driving the sleeve home locks the plain shaft without shoulders or screw points. read the 45 mm bore from the H 2310 sleeve designation — the YSA code marks the bearing seat size and the sleeve series is offset by one (sleeve code 310 clamps the 45 mm shaft). the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 45x90x37 mm (1.772x3.543x1.457 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. Mounted width B1 55 mm includes the adapter sleeve. Supplied/specified with H 2310. The catalogue publishes a single speed ceiling, the limiting speed: 4,000 r/min; mass 970 g. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 62.5 mm, d3 70 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Load balance for documentation: C0 23.2 kN against C 35.1 kN gives a 0.661 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Pitch-diameter arithmetic: dm = (45+90)/2 = 67.5 mm; at the 4,000 r/min limiting speed the ball set runs at dn approx 2.70x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. The s1 31.1 mm dimension is printed for the locking zone — the distance before the adapter sleeve is driven up the taper — and it is verified at mounting, not recoverable from d/D/B alone. Rating split for the maintenance file: dynamic 35.1 kN (L10), static 23.2 kN (s0 shock check), fatigue 0.98 kN (adjusted life) — three separate uses for YSA 210-2FK H 2310, none interchangeable with another. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Mounting sequence for YSA-210-2FK-H-2310: slide H 2310 on first, seat the bearing in the housing register, then draw the nut to drive-up — reversing the order (sleeve fully tightened before housing engagement) locks in misalignment the sphered seat cannot cure.", "applications": [ "general transmission arrangements on h6 plain shafts", "fan and blower shafts of plain commercial steel", "ventilation equipment with long through-shafts" ], "failure_modes": [ "locknut not secured (no tab or thread locking): the sleeve unwinds under vibration and the unit collapses axially", "shaft shoulder absent or too small: the sleeve pulls through the bore instead of reacting the drive-up", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "Sleeve drive-up uses the printed s1 31.1 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "The order number is incomplete without the sleeve: YSA-210-2FK-H-2310 specifies the H 2310 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Ordering discipline for the 45 mm size: the chapter lists several executions side by side (YSA2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-210-2FK-H-2310?", "a": "Boundary dimensions: bore 45 mm, sphered OD 90 mm, overall width 37 mm (55 mm with the sleeve); weight 970 g. Loads: dynamic 35.1 kN, static 23.2 kN, fatigue 0.98 kN; the only published speed is the 4,000 r/min limiting value." }, { "q": "What does the designation YSA 210-2FK H 2310 mean?", "a": "reading YSA: the inner-ring bore is tapered 1:12 and the bearing ships/specifies with its H 2310 adapter sleeve; driving the sleeve home locks the plain shaft without shoulders or screw points. read the 45 mm bore from the H 2310 sleeve designation — the YSA code marks the bearing seat size and the sleeve series is offset by one (sleeve code 310 clamps the 45 mm shaft). the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (31.1 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." }, { "q": "What is the difference between H, HA and HE sleeves?", "a": "H sleeves fit metric shafts while HA/HE cover inch-shaft sizes of the same tapered insert; the sleeve designation, not the bearing code, determines the actual shaft diameter — always specify the bearing AND sleeve together." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-210-2FK-H-2310", "YSA 210-2FK H 2310" ], "locale_variants": {} }, { "sku": "YSA-211-2FK-H-2311", "brand": "SKF", "manufacturer_designation": "YSA 211-2FK H 2311", "series": "YSA2-series", "type": "insert", "d_mm": 50, "D_mm": 100, "B_mm": 40, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 1250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSA2 series order number YSA 211-2FK H 2311 is a SKF insert bearing (Y-bearing) for a 50 mm shaft: tapered-bore (1:12) insert bearing supplied on its H 2311 adapter sleeve, built to the ISO 15 diameter-series envelope with a sphered OD of 100 mm. Inside is a sealed, symmetrically extended ball insert with a tapered bore, the adapter sleeve converting a plain commercial shaft into a precision seat without shoulders, screw points or collars. reading YSA: the inner-ring bore is tapered 1:12 and the bearing ships/specifies with its H 2311 adapter sleeve; driving the sleeve home locks the plain shaft without shoulders or screw points. read the 50 mm bore from the H 2311 sleeve designation — the YSA code marks the bearing seat size and the sleeve series is offset by one (sleeve code 311 clamps the 50 mm shaft). the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 50x100x40 mm (1.969x3.937x1.575 in), outer ring 25 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. Mounted width B1 59 mm includes the adapter sleeve. Supplied/specified with H 2311. The catalogue publishes a single speed ceiling, the limiting speed: 3,600 r/min; mass 1250 g. The s1 32.5 mm dimension is printed for the locking zone — the distance before the adapter sleeve is driven up the taper — and it is verified at mounting, not recoverable from d/D/B alone. Fillet discipline: the printed minimum-fillet limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 50x100 mm insert on its chamfer tilts the whole spherical seat. Fatigue-limit check: Pu 1.25 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YSA 211-2FK H 2311 — most belt-driven mounted-unit loads sit comfortably under 2.867 % of C. Spherical-seat note in numbers: the 100 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 75 = 235.619 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Mass-to-load ratio for YSA-211-2FK-H-2311: 28.67 g of catalogue mass per rated kN of C, and 25 g per millimetre of bore — useful when comparing executions of the same 50x100 mm envelope on the drawing. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Sleeve geometry on YSA-211-2FK-H-2311: H 2311 pulls the tapered inner ring onto the 50 mm plain shaft; the printed s1 32.5 mm is the pre-drive distance and 59 mm is the overall width including the sleeve hardware.", "applications": [ "fan and blower shafts of plain commercial steel", "ventilation equipment with long through-shafts", "general transmission arrangements on h6 plain shafts" ], "failure_modes": [ "shaft shoulder absent or too small: the sleeve pulls through the bore instead of reacting the drive-up", "sleeve over-tightened: internal clearance vanishes and the bearing runs hot from the first hours", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The order number is incomplete without the sleeve: YSA-211-2FK-H-2311 specifies the H 2311 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "Sleeve drive-up uses the printed s1 32.5 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "Catalogue ratings belong to YSA 211-2FK H 2311 as the adapter two f execution; other order numbers of the YSA 211-2FK size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-211-2FK-H-2311?", "a": "Boundary dimensions: bore 50 mm, sphered OD 100 mm, overall width 40 mm (59 mm with the sleeve); weight 1250 g. Loads: dynamic 43.6 kN, static 29 kN, fatigue 1.25 kN; the only published speed is the 3,600 r/min limiting value." }, { "q": "What does the designation YSA 211-2FK H 2311 mean?", "a": "reading YSA: the inner-ring bore is tapered 1:12 and the bearing ships/specifies with its H 2311 adapter sleeve; driving the sleeve home locks the plain shaft without shoulders or screw points. read the 50 mm bore from the H 2311 sleeve designation — the YSA code marks the bearing seat size and the sleeve series is offset by one (sleeve code 311 clamps the 50 mm shaft). the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Why is the bore tapered and what is the H 2311 sleeve?", "a": "The inner ring has a 1:12 tapered bore (K); the H 2311 adapter sleeve is drawn between taper and a plain 50 mm shaft by a locknut, giving a precise, demountable concentric seat without shaft shoulders." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-211-2FK-H-2311", "YSA 211-2FK H 2311" ], "locale_variants": {} }, { "sku": "YSA-212-2FK-H-2312", "brand": "SKF", "manufacturer_designation": "YSA 212-2FK H 2312", "series": "YSA2-series", "type": "insert", "d_mm": 55, "D_mm": 110, "B_mm": 42.5, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 36, "fatigue_load_limit_kN": 1.53, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 1550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSA 212-2FK H 2312 is SKF's 55 mm-bore tapered-bore (1:12) insert bearing supplied on its H 2312 adapter sleeve in the YSA2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 55x110x42.5 mm. The inner ring carries a 1:12 tapered bore and mounts on the specified adapter sleeve: tightening the sleeve nut draws the ring home on a plain shaft, while the sphered outer ring pivots in the Y-housing. YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the H 2312 sleeve is drawn up the taper to clamp a plain 55 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the H 2312 adapter sleeve, not by the bearing code: the sleeve seats a 55 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 55x110x42.5 mm (2.165x4.331x1.673 in), outer ring 26 mm wide, C 52.7 kN, C0 36 kN, Pu 1.53 kN. Mounted width B1 62 mm includes the adapter sleeve. Supplied/specified with H 2312. The catalogue publishes a single speed ceiling, the limiting speed: 3,400 r/min; mass 1550 g. Imperial procurement cross-check: 2.165 in bore, 4.331 in OD, 1.673 in overall width; the 1550 g mass converts to 1.550 kg (54.7 oz) for the bill of materials. Width accounting: B1 62 mm covers the bearing WITH its adapter-sleeve hardware against 42.5 mm for the bearing itself and 26 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Fillet discipline: the printed minimum-fillet limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 55x110 mm insert on its chamfer tilts the whole spherical seat. Envelope arithmetic: the radial section from 55 mm bore to 110 mm OD is 27.5 mm; dividing C 52.7 kN by that section gives 1.916 kN per section millimetre, and the 42.5 mm overall width is 1.545x the section. Outer-vs-overall width: the outer ring is 26 mm wide inside the 42.5 mm total, so the extended inner ring accounts for 0.388 of the overall width (8.25 mm of axial projection per side). Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Sleeve geometry on YSA-212-2FK-H-2312: H 2312 pulls the tapered inner ring onto the 55 mm plain shaft; the printed s1 33.8 mm is the pre-drive distance and 62 mm is the overall width including the sleeve hardware.", "applications": [ "fan and blower shafts of plain commercial steel", "general transmission arrangements on h6 plain shafts", "ventilation equipment with long through-shafts" ], "failure_modes": [ "shaft shoulder absent or too small: the sleeve pulls through the bore instead of reacting the drive-up", "locknut not secured (no tab or thread locking): the sleeve unwinds under vibration and the unit collapses axially", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Sleeve drive-up uses the printed s1 33.8 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "The order number is incomplete without the sleeve: YSA-212-2FK-H-2312 specifies the H 2312 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "The 52.7/36 kN figures belong specifically to YSA 212-2FK H 2312; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-212-2FK-H-2312?", "a": "YSA 212-2FK H 2312 measures 55 mm bore x 110 mm OD x 42.5 mm overall width (outer ring 26 mm wide), 2.165 x 4.331 x 1.673 in; mass about 1550 g. SKF 17000 ratings: C 52.7 kN, C0 36 kN, Pu 1.53 kN, limiting speed 3,400 r/min." }, { "q": "What does the designation YSA 212-2FK H 2312 mean?", "a": "YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the H 2312 sleeve is drawn up the taper to clamp a plain 55 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the H 2312 adapter sleeve, not by the bearing code: the sleeve seats a 55 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (33.8 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." }, { "q": "What is the difference between H, HA and HE sleeves?", "a": "H sleeves fit metric shafts while HA/HE cover inch-shaft sizes of the same tapered insert; the sleeve designation, not the bearing code, determines the actual shaft diameter — always specify the bearing AND sleeve together." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-212-2FK-H-2312", "YSA 212-2FK H 2312" ], "locale_variants": {} }, { "sku": "YSA-213-2FK-H-2313", "brand": "SKF", "manufacturer_designation": "YSA 213-2FK H 2313", "series": "YSA2-series", "type": "insert", "d_mm": 60, "D_mm": 120, "B_mm": 43.5, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 57.2, "static_load_kN": 40, "fatigue_load_limit_kN": 1.7, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 1900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSA2 series order number YSA 213-2FK H 2313 is a SKF insert bearing (Y-bearing) for a 60 mm shaft: tapered-bore (1:12) insert bearing supplied on its H 2313 adapter sleeve, built to the ISO 15 diameter-series envelope with a sphered OD of 120 mm. Inside is a sealed, symmetrically extended ball insert with a tapered bore, the adapter sleeve converting a plain commercial shaft into a precision seat without shoulders, screw points or collars. reading YSA: the inner-ring bore is tapered 1:12 and the bearing ships/specifies with its H 2313 adapter sleeve; driving the sleeve home locks the plain shaft without shoulders or screw points. read the 60 mm bore from the H 2313 sleeve designation — the YSA code marks the bearing seat size and the sleeve series is offset by one (sleeve code 313 clamps the 60 mm shaft). the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 60x120x43.5 mm (2.362x4.724x1.713 in), outer ring 27 mm wide, C 57.2 kN, C0 40 kN, Pu 1.7 kN. Mounted width B1 65 mm includes the adapter sleeve. Supplied/specified with H 2313. The catalogue publishes a single speed ceiling, the limiting speed: 3,000 r/min; mass 1900 g. At the printed limiting speed of 3,000 r/min the mean diameter dm = 90 mm implies dn about 2.70x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Pitch-diameter arithmetic: dm = (60+120)/2 = 90 mm; at the 3,000 r/min limiting speed the ball set runs at dn approx 2.70x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Static-first planning: the 0.92 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 60 mm shaft, not the 57.2 kN L10 value. The s1 35.3 mm dimension is printed for the locking zone — the distance before the adapter sleeve is driven up the taper — and it is verified at mounting, not recoverable from d/D/B alone. Mass-to-load ratio for YSA-213-2FK-H-2313: 33.217 g of catalogue mass per rated kN of C, and 31.667 g per millimetre of bore — useful when comparing executions of the same 60x120 mm envelope on the drawing. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Mounting sequence for YSA-213-2FK-H-2313: slide H 2313 on first, seat the bearing in the housing register, then draw the nut to drive-up — reversing the order (sleeve fully tightened before housing engagement) locks in misalignment the sphered seat cannot cure.", "applications": [ "mill auxiliary drives with frequent bearing changes", "heavy fan and process fan shafts", "bulk conveyor positions on plain shafting" ], "failure_modes": [ "locknut not secured (no tab or thread locking): the sleeve unwinds under vibration and the unit collapses axially", "sleeve over-tightened: internal clearance vanishes and the bearing runs hot from the first hours", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The order number is incomplete without the sleeve: YSA-213-2FK-H-2313 specifies the H 2313 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Sleeve drive-up uses the printed s1 35.3 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "Catalogue ratings belong to YSA 213-2FK H 2313 as the adapter two f execution; other order numbers of the YSA 213-2FK size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-213-2FK-H-2313?", "a": "Boundary dimensions: bore 60 mm, sphered OD 120 mm, overall width 43.5 mm (65 mm with the sleeve); weight 1900 g. Loads: dynamic 57.2 kN, static 40 kN, fatigue 1.7 kN; the only published speed is the 3,000 r/min limiting value." }, { "q": "What does the designation YSA 213-2FK H 2313 mean?", "a": "reading YSA: the inner-ring bore is tapered 1:12 and the bearing ships/specifies with its H 2313 adapter sleeve; driving the sleeve home locks the plain shaft without shoulders or screw points. read the 60 mm bore from the H 2313 sleeve designation — the YSA code marks the bearing seat size and the sleeve series is offset by one (sleeve code 313 clamps the 60 mm shaft). the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "Why is the bore tapered and what is the H 2313 sleeve?", "a": "The inner ring has a 1:12 tapered bore (K); the H 2313 adapter sleeve is drawn between taper and a plain 60 mm shaft by a locknut, giving a precise, demountable concentric seat without shaft shoulders." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-213-2FK-H-2313", "YSA 213-2FK H 2313" ], "locale_variants": {} }, { "sku": "YSA-205-2FK-HE-2305", "brand": "SKF", "manufacturer_designation": "YSA 205-2FK HE 2305", "series": "YSA2-series", "type": "insert", "d_mm": 19.05, "D_mm": 52, "B_mm": 24, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 7000, "max_rpm": 7000, "weight_g": 250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSA 205-2FK HE 2305 is SKF's 19.05 mm-bore tapered-bore (1:12) insert bearing supplied on its HE 2305 adapter sleeve in the YSA2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 19.05x52x24 mm. The inner ring carries a 1:12 tapered bore and mounts on the specified adapter sleeve: tightening the sleeve nut draws the ring home on a plain shaft, while the sphered outer ring pivots in the Y-housing. YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the HE 2305 sleeve is drawn up the taper to clamp a plain 19.05 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the HE 2305 adapter sleeve, not by the bearing code: the sleeve seats a 19.05 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 19.05x52x24 mm (0.75x2.047x0.945 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. Mounted width B1 35 mm includes the adapter sleeve. Supplied/specified with HE 2305. The catalogue publishes a single speed ceiling, the limiting speed: 7,000 r/min; mass 250 g. Fatigue-limit check: Pu 0.335 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YSA 205-2FK HE 2305 — most belt-driven mounted-unit loads sit comfortably under 2.393 % of C. Rating split for the maintenance file: dynamic 14 kN (L10), static 7.8 kN (s0 shock check), fatigue 0.335 kN (adjusted life) — three separate uses for YSA 205-2FK HE 2305, none interchangeable with another. At the printed limiting speed of 7,000 r/min the mean diameter dm = 35.525 mm implies dn about 2.49x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Imperial procurement cross-check: 0.75 in bore, 2.047 in OD, 0.945 in overall width; the 250 g mass converts to 0.250 kg (8.8 oz) for the bill of materials. Mass-to-load ratio for YSA-205-2FK-HE-2305: 17.857 g of catalogue mass per rated kN of C, and 13.123 g per millimetre of bore — useful when comparing executions of the same 19.05x52 mm envelope on the drawing. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Sleeve geometry on YSA-205-2FK-HE-2305: HE 2305 pulls the tapered inner ring onto the 19.05 mm plain shaft; the printed s1 20.5 mm is the pre-drive distance and 35 mm is the overall width including the sleeve hardware.", "applications": [ "light transmission shafts without shoulders", "small fans on plain drawn shafts" ], "failure_modes": [ "locknut not secured (no tab or thread locking): the sleeve unwinds under vibration and the unit collapses axially", "sleeve under-tightened: the tapered inner ring creeps on the sleeve and polishes the taper bright", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Sleeve drive-up uses the printed s1 20.5 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "The order number is incomplete without the sleeve: YSA-205-2FK-HE-2305 specifies the HE 2305 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "The 14/7.8 kN figures belong specifically to YSA 205-2FK HE 2305; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-205-2FK-HE-2305?", "a": "YSA 205-2FK HE 2305 measures 19.05 mm bore x 52 mm OD x 24 mm overall width (outer ring 15 mm wide), 0.75 x 2.047 x 0.945 in; mass about 250 g. SKF 17000 ratings: C 14 kN, C0 7.8 kN, Pu 0.335 kN, limiting speed 7,000 r/min." }, { "q": "What does the designation YSA 205-2FK HE 2305 mean?", "a": "YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the HE 2305 sleeve is drawn up the taper to clamp a plain 19.05 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the HE 2305 adapter sleeve, not by the bearing code: the sleeve seats a 19.05 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (20.5 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-205-2FK-HE-2305", "YSA 205-2FK HE 2305" ], "locale_variants": {} }, { "sku": "YSA-206-2FK-HA-2306", "brand": "SKF", "manufacturer_designation": "YSA 206-2FK HA 2306", "series": "YSA2-series", "type": "insert", "d_mm": 23.812, "D_mm": 62, "B_mm": 28, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 390, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSA2 series order number YSA 206-2FK HA 2306 is a SKF insert bearing (Y-bearing) for a 23.812 mm (0.937 in) shaft: tapered-bore (1:12) insert bearing supplied on its HA 2306 adapter sleeve, built to the ISO 15 diameter-series envelope with a sphered OD of 62 mm. Inside is a sealed, symmetrically extended ball insert with a tapered bore, the adapter sleeve converting a plain commercial shaft into a precision seat without shoulders, screw points or collars. reading YSA: the inner-ring bore is tapered 1:12 and the bearing ships/specifies with its HA 2306 adapter sleeve; driving the sleeve home locks the plain shaft without shoulders or screw points. read the 23.812 mm bore from the HA 2306 sleeve designation — the YSA code marks the bearing seat size and the sleeve series is offset by one (sleeve code 2306 clamps the 23.812 mm shaft). the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 23.812x62x28 mm (0.937x2.441x1.102 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. Mounted width B1 38 mm includes the adapter sleeve. Supplied/specified with HA 2306. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 390 g. At the printed limiting speed of 6,300 r/min the mean diameter dm = 42.906 mm implies dn about 2.70x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Rating split for the maintenance file: dynamic 19.5 kN (L10), static 11.2 kN (s0 shock check), fatigue 0.475 kN (adjusted life) — three separate uses for YSA 206-2FK HA 2306, none interchangeable with another. Grease-life arithmetic is dominated by speed: at dn approx 2.70x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. The s1 22.5 mm dimension is printed for the locking zone — the distance before the adapter sleeve is driven up the taper — and it is verified at mounting, not recoverable from d/D/B alone. Fillet discipline: the printed minimum-fillet limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 23.812x62 mm insert on its chamfer tilts the whole spherical seat. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Sleeve geometry on YSA-206-2FK-HA-2306: HA 2306 pulls the tapered inner ring onto the 23.812 mm plain shaft; the printed s1 22.5 mm is the pre-drive distance and 38 mm is the overall width including the sleeve hardware.", "applications": [ "general transmission arrangements on h6 plain shafts", "conveyor positions needing easy removal without shaft damage", "ventilation equipment with long through-shafts" ], "failure_modes": [ "locknut not secured (no tab or thread locking): the sleeve unwinds under vibration and the unit collapses axially", "sleeve under-tightened: the tapered inner ring creeps on the sleeve and polishes the taper bright", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The order number is incomplete without the sleeve: YSA-206-2FK-HA-2306 specifies the HA 2306 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "Sleeve drive-up uses the printed s1 22.5 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "Catalogue ratings belong to YSA 206-2FK HA 2306 as the adapter two f execution; other order numbers of the YSA 206-2FK size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-206-2FK-HA-2306?", "a": "Boundary dimensions: bore 23.812 mm, sphered OD 62 mm, overall width 28 mm (38 mm with the sleeve); weight 390 g. Loads: dynamic 19.5 kN, static 11.2 kN, fatigue 0.475 kN; the only published speed is the 6,300 r/min limiting value." }, { "q": "What does the designation YSA 206-2FK HA 2306 mean?", "a": "reading YSA: the inner-ring bore is tapered 1:12 and the bearing ships/specifies with its HA 2306 adapter sleeve; driving the sleeve home locks the plain shaft without shoulders or screw points. read the 23.812 mm bore from the HA 2306 sleeve designation — the YSA code marks the bearing seat size and the sleeve series is offset by one (sleeve code 2306 clamps the 23.812 mm shaft). the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (22.5 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-206-2FK-HA-2306", "YSA 206-2FK HA 2306" ], "locale_variants": {} }, { "sku": "YSA-206-2FK-HE-2306", "brand": "SKF", "manufacturer_designation": "YSA 206-2FK HE 2306", "series": "YSA2-series", "type": "insert", "d_mm": 25.4, "D_mm": 62, "B_mm": 28, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 370, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSA 206-2FK HE 2306 is a tapered-bore (1:12) insert bearing supplied on its HE 2306 adapter sleeve, 25.4x62x28 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction combines capped deep-groove geometry, a tapered inner-ring bore and the supplied adapter sleeve with locknut seating — factory-grade concentricity on plain drawn shafting. YSA is the adapter-sleeve member of the Y range — tapered bore plus the HE 2306 sleeve converts a plain commercial shaft into a precisely located, demountable seat at 25.4 mm. adapter mounting means the effective bore is the sleeve bore: HE 2306 gives the 25.4 mm shaft fit with no machined shoulder required. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 25.4x62x28 mm (1x2.441x1.102 in), outer ring 18 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. Mounted width B1 38 mm includes the adapter sleeve. Supplied/specified with HE 2306. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 370 g. Fatigue-limit check: Pu 0.475 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YSA 206-2FK HE 2306 — most belt-driven mounted-unit loads sit comfortably under 2.436 % of C. Rating split for the maintenance file: dynamic 19.5 kN (L10), static 11.2 kN (s0 shock check), fatigue 0.475 kN (adjusted life) — three separate uses for YSA 206-2FK HE 2306, none interchangeable with another. Spherical-seat note in numbers: the 62 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 43.7 = 137.288 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Grease-life arithmetic is dominated by speed: at dn approx 2.75x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Bore-to-OD planning: OD 62 over bore 25.4 is a 2.441x step, while bore/overall-width gives 0.907; the spherical seat in the matching Y-housing must be specified to the 62 mm OD, not to a cylindrical housing bore. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Sleeve geometry on YSA-206-2FK-HE-2306: HE 2306 pulls the tapered inner ring onto the 25.4 mm plain shaft; the printed s1 22.5 mm is the pre-drive distance and 38 mm is the overall width including the sleeve hardware.", "applications": [ "general transmission arrangements on h6 plain shafts", "conveyor positions needing easy removal without shaft damage", "ventilation equipment with long through-shafts" ], "failure_modes": [ "locknut not secured (no tab or thread locking): the sleeve unwinds under vibration and the unit collapses axially", "sleeve under-tightened: the tapered inner ring creeps on the sleeve and polishes the taper bright", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The order number is incomplete without the sleeve: YSA-206-2FK-HE-2306 specifies the HE 2306 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Sleeve drive-up uses the printed s1 22.5 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "Catalogue ratings belong to YSA 206-2FK HE 2306 as the adapter two f execution; other order numbers of the YSA 206-2FK size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-206-2FK-HE-2306?", "a": "The catalogue envelope is 25.4x62x28 mm with a spherical outside surface; mass 370 g. Ratings C 19.5/11.2 kN, Pu 0.475 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation YSA 206-2FK HE 2306 mean?", "a": "YSA is the adapter-sleeve member of the Y range — tapered bore plus the HE 2306 sleeve converts a plain commercial shaft into a precisely located, demountable seat at 25.4 mm. adapter mounting means the effective bore is the sleeve bore: HE 2306 gives the 25.4 mm shaft fit with no machined shoulder required. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (22.5 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." } ], "cross_ref": [ { "equiv_sku": "YSA-206-2FK-H-2306", "equiv_brand": "SKF", "level": "full", "note": "Same 25.4x62x28 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSA 206-2FK H 2306 is the tapered bore on H 2306 adapter sleeve execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 25.4 mm vs 25 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-206-2FK-HE-2306", "YSA 206-2FK HE 2306" ], "locale_variants": {} }, { "sku": "YSA-207-2FK-HA-2307", "brand": "SKF", "manufacturer_designation": "YSA 207-2FK HA 2307", "series": "YSA2-series", "type": "insert", "d_mm": 30.15, "D_mm": 72, "B_mm": 30.5, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 5300, "max_rpm": 5300, "weight_g": 540, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The YSA2 series order number YSA 207-2FK HA 2307 is a SKF insert bearing (Y-bearing) for a 30.15 mm (1.187 in) shaft: tapered-bore (1:12) insert bearing supplied on its HA 2307 adapter sleeve, built to the ISO 15 diameter-series envelope with a sphered OD of 72 mm. Inside is a sealed, symmetrically extended ball insert with a tapered bore, the adapter sleeve converting a plain commercial shaft into a precision seat without shoulders, screw points or collars. reading YSA: the inner-ring bore is tapered 1:12 and the bearing ships/specifies with its HA 2307 adapter sleeve; driving the sleeve home locks the plain shaft without shoulders or screw points. read the 30.15 mm bore from the HA 2307 sleeve designation — the YSA code marks the bearing seat size and the sleeve series is offset by one (sleeve code 2307 clamps the 30.15 mm shaft). the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 30.15x72x30.5 mm (1.187x2.835x1.201 in), outer ring 19 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. Mounted width B1 43 mm includes the adapter sleeve. Supplied/specified with HA 2307. The catalogue publishes a single speed ceiling, the limiting speed: 5,300 r/min; mass 540 g. Envelope arithmetic: the radial section from 30.15 mm bore to 72 mm OD is 20.925 mm; dividing C 25.5 kN by that section gives 1.219 kN per section millimetre, and the 30.5 mm overall width is 1.458x the section. Rating split for the maintenance file: dynamic 25.5 kN (L10), static 15.3 kN (s0 shock check), fatigue 0.655 kN (adjusted life) — three separate uses for YSA 207-2FK HA 2307, none interchangeable with another. Static-first planning: the 0.502 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 30.15 mm shaft, not the 25.5 kN L10 value. Pitch-diameter arithmetic: dm = (30.15+72)/2 = 51.075 mm; at the 5,300 r/min limiting speed the ball set runs at dn approx 2.71x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Outer-vs-overall width: the outer ring is 19 mm wide inside the 30.5 mm total, so the extended inner ring accounts for 0.377 of the overall width (5.75 mm of axial projection per side). Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Mounting sequence for YSA-207-2FK-HA-2307: slide HA 2307 on first, seat the bearing in the housing register, then draw the nut to drive-up — reversing the order (sleeve fully tightened before housing engagement) locks in misalignment the sphered seat cannot cure.", "applications": [ "ventilation equipment with long through-shafts", "conveyor positions needing easy removal without shaft damage", "fan and blower shafts of plain commercial steel" ], "failure_modes": [ "sleeve over-tightened: internal clearance vanishes and the bearing runs hot from the first hours", "sleeve under-tightened: the tapered inner ring creeps on the sleeve and polishes the taper bright", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "Sleeve drive-up uses the printed s1 24.8 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "The order number is incomplete without the sleeve: YSA-207-2FK-HA-2307 specifies the HA 2307 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "The 25.5/15.3 kN figures belong specifically to YSA 207-2FK HA 2307; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-207-2FK-HA-2307?", "a": "Boundary dimensions: bore 30.15 mm, sphered OD 72 mm, overall width 30.5 mm (43 mm with the sleeve); weight 540 g. Loads: dynamic 25.5 kN, static 15.3 kN, fatigue 0.655 kN; the only published speed is the 5,300 r/min limiting value." }, { "q": "What does the designation YSA 207-2FK HA 2307 mean?", "a": "reading YSA: the inner-ring bore is tapered 1:12 and the bearing ships/specifies with its HA 2307 adapter sleeve; driving the sleeve home locks the plain shaft without shoulders or screw points. read the 30.15 mm bore from the HA 2307 sleeve designation — the YSA code marks the bearing seat size and the sleeve series is offset by one (sleeve code 2307 clamps the 30.15 mm shaft). the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (24.8 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." } ], "cross_ref": [ { "equiv_sku": "YSA-207-2FK-H-2307", "equiv_brand": "SKF", "level": "full", "note": "Same 30.15x72x30.5 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; YSA 207-2FK H 2307 is the tapered bore on H 2307 adapter sleeve execution of this size — boundary dimensions interchangeable, locking/seal execution differs. NOTE the bore differs: 30.15 mm vs 30 mm (inch-coded vs metric shaft size) — same bearing envelope, NOT interchangeable shafts." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-207-2FK-HA-2307", "YSA 207-2FK HA 2307" ], "locale_variants": {} }, { "sku": "YSA-208-2FK-HE-2308", "brand": "SKF", "manufacturer_designation": "YSA 208-2FK HE 2308", "series": "YSA2-series", "type": "insert", "d_mm": 31.75, "D_mm": 80, "B_mm": 33.9, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 770, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSA 208-2FK HE 2308 is a tapered-bore (1:12) insert bearing supplied on its HE 2308 adapter sleeve, 31.75x80x33.9 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction combines capped deep-groove geometry, a tapered inner-ring bore and the supplied adapter sleeve with locknut seating — factory-grade concentricity on plain drawn shafting. YSA is the adapter-sleeve member of the Y range — tapered bore plus the HE 2308 sleeve converts a plain commercial shaft into a precisely located, demountable seat at 31.75 mm. adapter mounting means the effective bore is the sleeve bore: HE 2308 gives the 31.75 mm shaft fit with no machined shoulder required. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 31.75x80x33.9 mm (1.25x3.15x1.335 in), outer ring 21 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. Mounted width B1 46 mm includes the adapter sleeve. Supplied/specified with HE 2308. The catalogue publishes a single speed ceiling, the limiting speed: 4,800 r/min; mass 770 g. Outer-vs-overall width: the outer ring is 21 mm wide inside the 33.9 mm total, so the extended inner ring accounts for 0.381 of the overall width (6.45 mm of axial projection per side). Rating split for the maintenance file: dynamic 30.7 kN (L10), static 19 kN (s0 shock check), fatigue 0.8 kN (adjusted life) — three separate uses for YSA 208-2FK HE 2308, none interchangeable with another. Width accounting: B1 46 mm covers the bearing WITH its adapter-sleeve hardware against 33.9 mm for the bearing itself and 21 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Spherical-seat note in numbers: the 80 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 55.875 = 175.536 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fillet discipline: the printed minimum-fillet limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 31.75x80 mm insert on its chamfer tilts the whole spherical seat. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Sleeve geometry on YSA-208-2FK-HE-2308: HE 2308 pulls the tapered inner ring onto the 31.75 mm plain shaft; the printed s1 27.5 mm is the pre-drive distance and 46 mm is the overall width including the sleeve hardware.", "applications": [ "conveyor positions needing easy removal without shaft damage", "fan and blower shafts of plain commercial steel", "general transmission arrangements on h6 plain shafts" ], "failure_modes": [ "sleeve under-tightened: the tapered inner ring creeps on the sleeve and polishes the taper bright", "shaft shoulder absent or too small: the sleeve pulls through the bore instead of reacting the drive-up", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks" ], "pitfalls": [ "The order number is incomplete without the sleeve: YSA-208-2FK-HE-2308 specifies the HE 2308 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "Sleeve drive-up uses the printed s1 27.5 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "Catalogue ratings belong to YSA 208-2FK HE 2308 as the adapter two f execution; other order numbers of the YSA 208-2FK size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-208-2FK-HE-2308?", "a": "The catalogue envelope is 31.75x80x33.9 mm with a spherical outside surface; mass 770 g. Ratings C 30.7/19 kN, Pu 0.8 kN, limiting speed 4,800 r/min." }, { "q": "What does the designation YSA 208-2FK HE 2308 mean?", "a": "YSA is the adapter-sleeve member of the Y range — tapered bore plus the HE 2308 sleeve converts a plain commercial shaft into a precisely located, demountable seat at 31.75 mm. adapter mounting means the effective bore is the sleeve bore: HE 2308 gives the 31.75 mm shaft fit with no machined shoulder required. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (27.5 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-208-2FK-HE-2308", "YSA 208-2FK HE 2308" ], "locale_variants": {} }, { "sku": "YSA-209-2FK-HA-2309", "brand": "SKF", "manufacturer_designation": "YSA 209-2FK HA 2309", "series": "YSA2-series", "type": "insert", "d_mm": 36.512, "D_mm": 85, "B_mm": 35, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 920, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSA 209-2FK HA 2309 is SKF's 36.512 mm-bore tapered-bore (1:12) insert bearing supplied on its HA 2309 adapter sleeve in the YSA2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 36.512x85x35 mm. The inner ring carries a 1:12 tapered bore and mounts on the specified adapter sleeve: tightening the sleeve nut draws the ring home on a plain shaft, while the sphered outer ring pivots in the Y-housing. YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the HA 2309 sleeve is drawn up the taper to clamp a plain 36.512 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the HA 2309 adapter sleeve, not by the bearing code: the sleeve seats a 36.512 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 36.512x85x35 mm (1.437x3.346x1.378 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. Mounted width B1 50 mm includes the adapter sleeve. Supplied/specified with HA 2309. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 920 g. Rating split for the maintenance file: dynamic 33.2 kN (L10), static 21.6 kN (s0 shock check), fatigue 0.915 kN (adjusted life) — three separate uses for YSA 209-2FK HA 2309, none interchangeable with another. At the printed limiting speed of 4,300 r/min the mean diameter dm = 60.756 mm implies dn about 2.61x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Spherical-seat note in numbers: the 85 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 60.756 = 190.871 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fatigue-limit check: Pu 0.915 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for YSA 209-2FK HA 2309 — most belt-driven mounted-unit loads sit comfortably under 2.756 % of C. Mass-to-load ratio for YSA-209-2FK-HA-2309: 27.711 g of catalogue mass per rated kN of C, and 25.197 g per millimetre of bore — useful when comparing executions of the same 36.512x85 mm envelope on the drawing. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Sleeve geometry on YSA-209-2FK-HA-2309: HA 2309 pulls the tapered inner ring onto the 36.512 mm plain shaft; the printed s1 29 mm is the pre-drive distance and 50 mm is the overall width including the sleeve hardware.", "applications": [ "general transmission arrangements on h6 plain shafts", "conveyor positions needing easy removal without shaft damage", "ventilation equipment with long through-shafts" ], "failure_modes": [ "locknut not secured (no tab or thread locking): the sleeve unwinds under vibration and the unit collapses axially", "sleeve under-tightened: the tapered inner ring creeps on the sleeve and polishes the taper bright", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "The order number is incomplete without the sleeve: YSA-209-2FK-HA-2309 specifies the HA 2309 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "Sleeve drive-up uses the printed s1 29 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "Catalogue ratings belong to YSA 209-2FK HA 2309 as the adapter two f execution; other order numbers of the YSA 209-2FK size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-209-2FK-HA-2309?", "a": "YSA 209-2FK HA 2309 measures 36.512 mm bore x 85 mm OD x 35 mm overall width (outer ring 22 mm wide), 1.437 x 3.346 x 1.378 in; mass about 920 g. SKF 17000 ratings: C 33.2 kN, C0 21.6 kN, Pu 0.915 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YSA 209-2FK HA 2309 mean?", "a": "YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the HA 2309 sleeve is drawn up the taper to clamp a plain 36.512 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the HA 2309 adapter sleeve, not by the bearing code: the sleeve seats a 36.512 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (29 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-209-2FK-HA-2309", "YSA 209-2FK HA 2309" ], "locale_variants": {} }, { "sku": "YSA-209-2FK-HE-2309", "brand": "SKF", "manufacturer_designation": "YSA 209-2FK HE 2309", "series": "YSA2-series", "type": "insert", "d_mm": 38.1, "D_mm": 85, "B_mm": 35, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 880, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSA 209-2FK HE 2309 is SKF's 38.1 mm-bore tapered-bore (1:12) insert bearing supplied on its HE 2309 adapter sleeve in the YSA2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 38.1x85x35 mm. The inner ring carries a 1:12 tapered bore and mounts on the specified adapter sleeve: tightening the sleeve nut draws the ring home on a plain shaft, while the sphered outer ring pivots in the Y-housing. YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the HE 2309 sleeve is drawn up the taper to clamp a plain 38.1 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the HE 2309 adapter sleeve, not by the bearing code: the sleeve seats a 38.1 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 38.1x85x35 mm (1.5x3.346x1.378 in), outer ring 22 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. Mounted width B1 50 mm includes the adapter sleeve. Supplied/specified with HE 2309. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 880 g. Pitch-diameter arithmetic: dm = (38.1+85)/2 = 61.55 mm; at the 4,300 r/min limiting speed the ball set runs at dn approx 2.65x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. At the printed limiting speed of 4,300 r/min the mean diameter dm = 61.55 mm implies dn about 2.65x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Static-first planning: the 0.617 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 38.1 mm shaft, not the 33.2 kN L10 value. Fillet discipline: the printed minimum-fillet limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 38.1x85 mm insert on its chamfer tilts the whole spherical seat. Outer-vs-overall width: the outer ring is 22 mm wide inside the 35 mm total, so the extended inner ring accounts for 0.371 of the overall width (6.5 mm of axial projection per side). Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Mounting sequence for YSA-209-2FK-HE-2309: slide HE 2309 on first, seat the bearing in the housing register, then draw the nut to drive-up — reversing the order (sleeve fully tightened before housing engagement) locks in misalignment the sphered seat cannot cure.", "applications": [ "ventilation equipment with long through-shafts", "conveyor positions needing easy removal without shaft damage", "fan and blower shafts of plain commercial steel" ], "failure_modes": [ "sleeve over-tightened: internal clearance vanishes and the bearing runs hot from the first hours", "sleeve under-tightened: the tapered inner ring creeps on the sleeve and polishes the taper bright", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "Sleeve drive-up uses the printed s1 29 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "The order number is incomplete without the sleeve: YSA-209-2FK-HE-2309 specifies the HE 2309 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "The 33.2/21.6 kN figures belong specifically to YSA 209-2FK HE 2309; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-209-2FK-HE-2309?", "a": "YSA 209-2FK HE 2309 measures 38.1 mm bore x 85 mm OD x 35 mm overall width (outer ring 22 mm wide), 1.5 x 3.346 x 1.378 in; mass about 880 g. SKF 17000 ratings: C 33.2 kN, C0 21.6 kN, Pu 0.915 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation YSA 209-2FK HE 2309 mean?", "a": "YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the HE 2309 sleeve is drawn up the taper to clamp a plain 38.1 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the HE 2309 adapter sleeve, not by the bearing code: the sleeve seats a 38.1 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (29 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-209-2FK-HE-2309", "YSA 209-2FK HE 2309" ], "locale_variants": {} }, { "sku": "YSA-210-2FK-HA-2310", "brand": "SKF", "manufacturer_designation": "YSA 210-2FK HA 2310", "series": "YSA2-series", "type": "insert", "d_mm": 42.862, "D_mm": 90, "B_mm": 37, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 1050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSA 210-2FK HA 2310 is a tapered-bore (1:12) insert bearing supplied on its HA 2310 adapter sleeve, 42.862x90x37 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction combines capped deep-groove geometry, a tapered inner-ring bore and the supplied adapter sleeve with locknut seating — factory-grade concentricity on plain drawn shafting. YSA is the adapter-sleeve member of the Y range — tapered bore plus the HA 2310 sleeve converts a plain commercial shaft into a precisely located, demountable seat at 42.862 mm. adapter mounting means the effective bore is the sleeve bore: HA 2310 gives the 42.862 mm shaft fit with no machined shoulder required. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 42.862x90x37 mm (1.687x3.543x1.457 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. Mounted width B1 55 mm includes the adapter sleeve. Supplied/specified with HA 2310. The catalogue publishes a single speed ceiling, the limiting speed: 4,000 r/min; mass 1050 g. Mass-to-load ratio for YSA-210-2FK-HA-2310: 29.915 g of catalogue mass per rated kN of C, and 24.497 g per millimetre of bore — useful when comparing executions of the same 42.862x90 mm envelope on the drawing. Rating split for the maintenance file: dynamic 35.1 kN (L10), static 23.2 kN (s0 shock check), fatigue 0.98 kN (adjusted life) — three separate uses for YSA 210-2FK HA 2310, none interchangeable with another. Load balance for documentation: C0 23.2 kN against C 35.1 kN gives a 0.661 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Bore-to-OD planning: OD 90 over bore 42.862 is a 2.1x step, while bore/overall-width gives 1.158; the spherical seat in the matching Y-housing must be specified to the 90 mm OD, not to a cylindrical housing bore. Width accounting: B1 55 mm covers the bearing WITH its adapter-sleeve hardware against 37 mm for the bearing itself and 22 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Mounting sequence for YSA-210-2FK-HA-2310: slide HA 2310 on first, seat the bearing in the housing register, then draw the nut to drive-up — reversing the order (sleeve fully tightened before housing engagement) locks in misalignment the sphered seat cannot cure.", "applications": [ "ventilation equipment with long through-shafts", "conveyor positions needing easy removal without shaft damage", "fan and blower shafts of plain commercial steel" ], "failure_modes": [ "sleeve over-tightened: internal clearance vanishes and the bearing runs hot from the first hours", "sleeve under-tightened: the tapered inner ring creeps on the sleeve and polishes the taper bright", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The order number is incomplete without the sleeve: YSA-210-2FK-HA-2310 specifies the HA 2310 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Sleeve drive-up uses the printed s1 31.1 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "Catalogue ratings belong to YSA 210-2FK HA 2310 as the adapter two f execution; other order numbers of the YSA 210-2FK size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-210-2FK-HA-2310?", "a": "The catalogue envelope is 42.862x90x37 mm with a spherical outside surface; mass 1050 g. Ratings C 35.1/23.2 kN, Pu 0.98 kN, limiting speed 4,000 r/min." }, { "q": "What does the designation YSA 210-2FK HA 2310 mean?", "a": "YSA is the adapter-sleeve member of the Y range — tapered bore plus the HA 2310 sleeve converts a plain commercial shaft into a precisely located, demountable seat at 42.862 mm. adapter mounting means the effective bore is the sleeve bore: HA 2310 gives the 42.862 mm shaft fit with no machined shoulder required. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (31.1 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-210-2FK-HA-2310", "YSA 210-2FK HA 2310" ], "locale_variants": {} }, { "sku": "YSA-210-2FK-HE-2310", "brand": "SKF", "manufacturer_designation": "YSA 210-2FK HE 2310", "series": "YSA2-series", "type": "insert", "d_mm": 44.45, "D_mm": 90, "B_mm": 37, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 980, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSA 210-2FK HE 2310 is a tapered-bore (1:12) insert bearing supplied on its HE 2310 adapter sleeve, 44.45x90x37 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction combines capped deep-groove geometry, a tapered inner-ring bore and the supplied adapter sleeve with locknut seating — factory-grade concentricity on plain drawn shafting. YSA is the adapter-sleeve member of the Y range — tapered bore plus the HE 2310 sleeve converts a plain commercial shaft into a precisely located, demountable seat at 44.45 mm. adapter mounting means the effective bore is the sleeve bore: HE 2310 gives the 44.45 mm shaft fit with no machined shoulder required. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 44.45x90x37 mm (1.75x3.543x1.457 in), outer ring 22 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. Mounted width B1 55 mm includes the adapter sleeve. Supplied/specified with HE 2310. The catalogue publishes a single speed ceiling, the limiting speed: 4,000 r/min; mass 980 g. Mass-to-load ratio for YSA-210-2FK-HE-2310: 27.92 g of catalogue mass per rated kN of C, and 22.047 g per millimetre of bore — useful when comparing executions of the same 44.45x90 mm envelope on the drawing. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 62.51 mm, d3 70 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Spherical-seat note in numbers: the 90 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 67.225 = 211.194 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Pitch-diameter arithmetic: dm = (44.45+90)/2 = 67.225 mm; at the 4,000 r/min limiting speed the ball set runs at dn approx 2.69x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Outer-vs-overall width: the outer ring is 22 mm wide inside the 37 mm total, so the extended inner ring accounts for 0.405 of the overall width (7.5 mm of axial projection per side). Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Mounting sequence for YSA-210-2FK-HE-2310: slide HE 2310 on first, seat the bearing in the housing register, then draw the nut to drive-up — reversing the order (sleeve fully tightened before housing engagement) locks in misalignment the sphered seat cannot cure.", "applications": [ "ventilation equipment with long through-shafts", "conveyor positions needing easy removal without shaft damage", "fan and blower shafts of plain commercial steel" ], "failure_modes": [ "sleeve over-tightened: internal clearance vanishes and the bearing runs hot from the first hours", "sleeve under-tightened: the tapered inner ring creeps on the sleeve and polishes the taper bright", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Sleeve drive-up uses the printed s1 31.1 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "The order number is incomplete without the sleeve: YSA-210-2FK-HE-2310 specifies the HE 2310 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "The 35.1/23.2 kN figures belong specifically to YSA 210-2FK HE 2310; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-210-2FK-HE-2310?", "a": "The catalogue envelope is 44.45x90x37 mm with a spherical outside surface; mass 980 g. Ratings C 35.1/23.2 kN, Pu 0.98 kN, limiting speed 4,000 r/min." }, { "q": "What does the designation YSA 210-2FK HE 2310 mean?", "a": "YSA is the adapter-sleeve member of the Y range — tapered bore plus the HE 2310 sleeve converts a plain commercial shaft into a precisely located, demountable seat at 44.45 mm. adapter mounting means the effective bore is the sleeve bore: HE 2310 gives the 44.45 mm shaft fit with no machined shoulder required. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (31.1 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-210-2FK-HE-2310", "YSA 210-2FK HE 2310" ], "locale_variants": {} }, { "sku": "YSA-211-2FK-HA-2311", "brand": "SKF", "manufacturer_designation": "YSA 211-2FK HA 2311", "series": "YSA2-series", "type": "insert", "d_mm": 49.212, "D_mm": 100, "B_mm": 40, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, YSA 211-2FK HA 2311 is a tapered-bore (1:12) insert bearing supplied on its HA 2311 adapter sleeve, 49.212x100x40 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction combines capped deep-groove geometry, a tapered inner-ring bore and the supplied adapter sleeve with locknut seating — factory-grade concentricity on plain drawn shafting. YSA is the adapter-sleeve member of the Y range — tapered bore plus the HA 2311 sleeve converts a plain commercial shaft into a precisely located, demountable seat at 49.212 mm. adapter mounting means the effective bore is the sleeve bore: HA 2311 gives the 49.212 mm shaft fit with no machined shoulder required. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution. Envelope 49.212x100x40 mm (1.937x3.937x1.575 in), outer ring 25 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. Mounted width B1 59 mm includes the adapter sleeve. Supplied/specified with HA 2311. The catalogue publishes a single speed ceiling, the limiting speed: 3,600 r/min; mass 1300 g. Speed ceiling of 3,600 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. At the printed limiting speed of 3,600 r/min the mean diameter dm = 74.606 mm implies dn about 2.69x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. The s1 32.5 mm dimension is printed for the locking zone — the distance before the adapter sleeve is driven up the taper — and it is verified at mounting, not recoverable from d/D/B alone. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 69.06 mm, d3 75 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Envelope arithmetic: the radial section from 49.212 mm bore to 100 mm OD is 25.394 mm; dividing C 43.6 kN by that section gives 1.717 kN per section millimetre, and the 40 mm overall width is 1.575x the section. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Sleeve geometry on YSA-211-2FK-HA-2311: HA 2311 pulls the tapered inner ring onto the 49.212 mm plain shaft; the printed s1 32.5 mm is the pre-drive distance and 59 mm is the overall width including the sleeve hardware.", "applications": [ "conveyor positions needing easy removal without shaft damage", "fan and blower shafts of plain commercial steel", "general transmission arrangements on h6 plain shafts" ], "failure_modes": [ "sleeve under-tightened: the tapered inner ring creeps on the sleeve and polishes the taper bright", "shaft shoulder absent or too small: the sleeve pulls through the bore instead of reacting the drive-up", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "The order number is incomplete without the sleeve: YSA-211-2FK-HA-2311 specifies the HA 2311 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Sleeve drive-up uses the printed s1 32.5 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "Ordering discipline for the 49.212 mm size: the chapter lists several executions side by side (YSA2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-211-2FK-HA-2311?", "a": "The catalogue envelope is 49.212x100x40 mm with a spherical outside surface; mass 1300 g. Ratings C 43.6/29 kN, Pu 1.25 kN, limiting speed 3,600 r/min." }, { "q": "What does the designation YSA 211-2FK HA 2311 mean?", "a": "YSA is the adapter-sleeve member of the Y range — tapered bore plus the HA 2311 sleeve converts a plain commercial shaft into a precisely located, demountable seat at 49.212 mm. adapter mounting means the effective bore is the sleeve bore: HA 2311 gives the 49.212 mm shaft fit with no machined shoulder required. -2F decodes to contact seals with additional plain flingers, one set per side; the unit is grease-filled for life and the flinger is why the sealed width exceeds the open one-side execution." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (32.5 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-211-2FK-HA-2311", "YSA 211-2FK HA 2311" ], "locale_variants": {} }, { "sku": "YSA-211-2FK-HE-2311", "brand": "SKF", "manufacturer_designation": "YSA 211-2FK HE 2311", "series": "YSA2-series", "type": "insert", "d_mm": 50.8, "D_mm": 100, "B_mm": 40, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSA 211-2FK HE 2311 is SKF's 50.8 mm-bore tapered-bore (1:12) insert bearing supplied on its HE 2311 adapter sleeve in the YSA2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 50.8x100x40 mm. The inner ring carries a 1:12 tapered bore and mounts on the specified adapter sleeve: tightening the sleeve nut draws the ring home on a plain shaft, while the sphered outer ring pivots in the Y-housing. YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the HE 2311 sleeve is drawn up the taper to clamp a plain 50.8 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the HE 2311 adapter sleeve, not by the bearing code: the sleeve seats a 50.8 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 50.8x100x40 mm (2x3.937x1.575 in), outer ring 25 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. Mounted width B1 59 mm includes the adapter sleeve. Supplied/specified with HE 2311. The catalogue publishes a single speed ceiling, the limiting speed: 3,600 r/min; mass 1200 g. Selection figures for YSA 211-2FK HE 2311: C0/C is 0.665, Pu 1.25 kN is 2.867 % of the 43.6 kN dynamic rating, and the 1200 g catalogue mass works out to roughly 23.622 g per millimetre of the 50.8 mm bore. At the printed limiting speed of 3,600 r/min the mean diameter dm = 75.4 mm implies dn about 2.71x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Capacity density: 43.6 kN from 1.200 kg of bearing steel is about 36.333 kN per kilogram, and per width millimetre the 40 mm unit carries 1.09 kN of dynamic capacity. Static-first planning: the 0.725 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 50.8 mm shaft, not the 43.6 kN L10 value. Grease-life arithmetic is dominated by speed: at dn approx 2.71x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Sleeve geometry on YSA-211-2FK-HE-2311: HE 2311 pulls the tapered inner ring onto the 50.8 mm plain shaft; the printed s1 32.5 mm is the pre-drive distance and 59 mm is the overall width including the sleeve hardware.", "applications": [ "conveyor positions needing easy removal without shaft damage", "fan and blower shafts of plain commercial steel", "general transmission arrangements on h6 plain shafts" ], "failure_modes": [ "sleeve under-tightened: the tapered inner ring creeps on the sleeve and polishes the taper bright", "shaft shoulder absent or too small: the sleeve pulls through the bore instead of reacting the drive-up", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "The order number is incomplete without the sleeve: YSA-211-2FK-HE-2311 specifies the HE 2311 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Sleeve drive-up uses the printed s1 32.5 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "Ordering discipline for the 50.8 mm size: the chapter lists several executions side by side (YSA2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-211-2FK-HE-2311?", "a": "YSA 211-2FK HE 2311 measures 50.8 mm bore x 100 mm OD x 40 mm overall width (outer ring 25 mm wide), 2 x 3.937 x 1.575 in; mass about 1200 g. SKF 17000 ratings: C 43.6 kN, C0 29 kN, Pu 1.25 kN, limiting speed 3,600 r/min." }, { "q": "What does the designation YSA 211-2FK HE 2311 mean?", "a": "YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the HE 2311 sleeve is drawn up the taper to clamp a plain 50.8 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the HE 2311 adapter sleeve, not by the bearing code: the sleeve seats a 50.8 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (32.5 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-211-2FK-HE-2311", "YSA 211-2FK HE 2311" ], "locale_variants": {} }, { "sku": "YSA-213-2FK-HA-2313", "brand": "SKF", "manufacturer_designation": "YSA 213-2FK HA 2313", "series": "YSA2-series", "type": "insert", "d_mm": 55.562, "D_mm": 120, "B_mm": 43.5, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 57.2, "static_load_kN": 40, "fatigue_load_limit_kN": 1.7, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 2100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSA 213-2FK HA 2313 is SKF's 55.562 mm-bore tapered-bore (1:12) insert bearing supplied on its HA 2313 adapter sleeve in the YSA2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 55.562x120x43.5 mm. The inner ring carries a 1:12 tapered bore and mounts on the specified adapter sleeve: tightening the sleeve nut draws the ring home on a plain shaft, while the sphered outer ring pivots in the Y-housing. YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the HA 2313 sleeve is drawn up the taper to clamp a plain 55.562 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the HA 2313 adapter sleeve, not by the bearing code: the sleeve seats a 55.562 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 55.562x120x43.5 mm (2.187x4.724x1.713 in), outer ring 27 mm wide, C 57.2 kN, C0 40 kN, Pu 1.7 kN. Mounted width B1 65 mm includes the adapter sleeve. Supplied/specified with HA 2313. The catalogue publishes a single speed ceiling, the limiting speed: 3,000 r/min; mass 2100 g. Selection figures for YSA 213-2FK HA 2313: C0/C is 0.699, Pu 1.7 kN is 2.972 % of the 57.2 kN dynamic rating, and the 2100 g catalogue mass works out to roughly 37.796 g per millimetre of the 55.562 mm bore. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 82.5 mm, d3 85 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the plain flinger. Capacity density: 57.2 kN from 2.100 kg of bearing steel is about 27.238 kN per kilogram, and per width millimetre the 43.5 mm unit carries 1.315 kN of dynamic capacity. Spherical-seat note in numbers: the 120 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 87.781 = 275.772 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Rating split for the maintenance file: dynamic 57.2 kN (L10), static 40 kN (s0 shock check), fatigue 1.7 kN (adjusted life) — three separate uses for YSA 213-2FK HA 2313, none interchangeable with another. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Sleeve geometry on YSA-213-2FK-HA-2313: HA 2313 pulls the tapered inner ring onto the 55.562 mm plain shaft; the printed s1 35.3 mm is the pre-drive distance and 65 mm is the overall width including the sleeve hardware.", "applications": [ "bulk conveyor positions on plain shafting", "mill auxiliary drives with frequent bearing changes", "heavy fan and process fan shafts" ], "failure_modes": [ "sleeve under-tightened: the tapered inner ring creeps on the sleeve and polishes the taper bright", "shaft shoulder absent or too small: the sleeve pulls through the bore instead of reacting the drive-up", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "The order number is incomplete without the sleeve: YSA-213-2FK-HA-2313 specifies the HA 2313 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Sleeve drive-up uses the printed s1 35.3 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "Ordering discipline for the 55.562 mm size: the chapter lists several executions side by side (YSA2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-213-2FK-HA-2313?", "a": "YSA 213-2FK HA 2313 measures 55.562 mm bore x 120 mm OD x 43.5 mm overall width (outer ring 27 mm wide), 2.187 x 4.724 x 1.713 in; mass about 2100 g. SKF 17000 ratings: C 57.2 kN, C0 40 kN, Pu 1.7 kN, limiting speed 3,000 r/min." }, { "q": "What does the designation YSA 213-2FK HA 2313 mean?", "a": "YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the HA 2313 sleeve is drawn up the taper to clamp a plain 55.562 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the HA 2313 adapter sleeve, not by the bearing code: the sleeve seats a 55.562 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (35.3 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-213-2FK-HA-2313", "YSA 213-2FK HA 2313" ], "locale_variants": {} }, { "sku": "YSA-213-2FK-HE-2313", "brand": "SKF", "manufacturer_designation": "YSA 213-2FK HE 2313", "series": "YSA2-series", "type": "insert", "d_mm": 57.15, "D_mm": 120, "B_mm": 43.5, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 57.2, "static_load_kN": 40, "fatigue_load_limit_kN": 1.7, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 2050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "YSA 213-2FK HE 2313 is SKF's 57.15 mm-bore tapered-bore (1:12) insert bearing supplied on its HE 2313 adapter sleeve in the YSA2 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 57.15x120x43.5 mm. The inner ring carries a 1:12 tapered bore and mounts on the specified adapter sleeve: tightening the sleeve nut draws the ring home on a plain shaft, while the sphered outer ring pivots in the Y-housing. YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the HE 2313 sleeve is drawn up the taper to clamp a plain 57.15 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the HE 2313 adapter sleeve, not by the bearing code: the sleeve seats a 57.15 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip. Envelope 57.15x120x43.5 mm (2.25x4.724x1.713 in), outer ring 27 mm wide, C 57.2 kN, C0 40 kN, Pu 1.7 kN. Mounted width B1 65 mm includes the adapter sleeve. Supplied/specified with HE 2313. The catalogue publishes a single speed ceiling, the limiting speed: 3,000 r/min; mass 2050 g. Load balance for documentation: C0 40 kN against C 57.2 kN gives a 0.699 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Rating split for the maintenance file: dynamic 57.2 kN (L10), static 40 kN (s0 shock check), fatigue 1.7 kN (adjusted life) — three separate uses for YSA 213-2FK HE 2313, none interchangeable with another. Mass-to-load ratio for YSA-213-2FK-HE-2313: 35.839 g of catalogue mass per rated kN of C, and 35.871 g per millimetre of bore — useful when comparing executions of the same 57.15x120 mm envelope on the drawing. Bore-to-OD planning: OD 120 over bore 57.15 is a 2.1x step, while bore/overall-width gives 1.314; the spherical seat in the matching Y-housing must be specified to the 120 mm OD, not to a cylindrical housing bore. Width accounting: B1 65 mm covers the bearing WITH its adapter-sleeve hardware against 43.5 mm for the bearing itself and 27 mm outer-ring width; housing axial space is drawn to B1, seal replacement space to B. Adapter-sleeve note: tighten the sleeve locknut to the catalogue axial drive-up (s1 is printed as the starting distance before the sleeve is driven into the tapered bore); under-tightening lets the inner ring creep, over-tightening eliminates internal clearance and preloads the balls hot. Mounting sequence for YSA-213-2FK-HE-2313: slide HE 2313 on first, seat the bearing in the housing register, then draw the nut to drive-up — reversing the order (sleeve fully tightened before housing engagement) locks in misalignment the sphered seat cannot cure.", "applications": [ "mill auxiliary drives with frequent bearing changes", "heavy fan and process fan shafts", "bulk conveyor positions on plain shafting" ], "failure_modes": [ "shaft shoulder absent or too small: the sleeve pulls through the bore instead of reacting the drive-up", "sleeve under-tightened: the tapered inner ring creeps on the sleeve and polishes the taper bright", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "Plain-shaft advantage is also its trap: with no shoulders, axial location comes entirely from the sleeve/nut reaction — the abutment behind the sleeve must be square and present.", "Sleeve drive-up uses the printed s1 35.3 mm starting distance, not a torque value guessed from locknut size; re-measure the residual gap after tightening rather than trusting feel.", "The order number is incomplete without the sleeve: YSA-213-2FK-HE-2313 specifies the HE 2313 adapter as part of the article; quoting only the YSA bearing risks delivery of a sleeve-less tapered bore that cannot mount.", "Ordering discipline for the 57.15 mm size: the chapter lists several executions side by side (YSA2 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of YSA-213-2FK-HE-2313?", "a": "YSA 213-2FK HE 2313 measures 57.15 mm bore x 120 mm OD x 43.5 mm overall width (outer ring 27 mm wide), 2.25 x 4.724 x 1.713 in; mass about 2050 g. SKF 17000 ratings: C 57.2 kN, C0 40 kN, Pu 1.7 kN, limiting speed 3,000 r/min." }, { "q": "What does the designation YSA 213-2FK HE 2313 mean?", "a": "YSA names the tapered-bore (K, 1:12 taper) insert mounted on an adapter sleeve: the HE 2313 sleeve is drawn up the taper to clamp a plain 57.15 mm shaft with a locknut, giving the concentricity and easy mounting of adapter-sleeve bearings. the shaft diameter is set by the HE 2313 adapter sleeve, not by the bearing code: the sleeve seats a 57.15 mm plain shaft under the tapered bore. suffix -2F means an NBR rubber contact seal plus a plain pressed-steel flinger on EACH side: the lip rides the extended inner ring while the flinger sheds coarse contamination before it reaches the lip." }, { "q": "What shaft preparation is needed?", "a": "A plain commercial shaft in the recommended tolerance, clean and free of burrs, with a light abutment for the sleeve face. No shoulders, dimples or collar space are required — that is the main advantage of adapter mounting." }, { "q": "How tight should the adapter sleeve be?", "a": "Drive-up is controlled by the printed axial procedure using the s1 starting distance (35.3 mm for this size). Too loose creeps; too tight removes internal clearance and overheats the ball set. Secure the locknut when finished." } ], "cross_ref": [ { "equiv_sku": "YSA", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "YSA-213-2FK-HE-2313", "YSA 213-2FK HE 2313" ], "locale_variants": {} }, { "sku": "1726203-2RS1", "brand": "SKF", "manufacturer_designation": "1726203-2RS1", "series": "17262-series", "type": "insert", "d_mm": 17, "D_mm": 40, "B_mm": 12, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 9.56, "static_load_kN": 4.75, "fatigue_load_limit_kN": 0.2, "limiting_speed_rpm": 12000, "max_rpm": 12000, "weight_g": 60, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "1726203-2RS1 is SKF's 17 mm-bore insert bearing with a standard (non-extended) inner ring in the 17262 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 17x40x12 mm. Unlike the extended-ring Y executions this is a standard-width sealed deep-groove ball insert: normal-width inner ring, spherically ground outer ring, static self-alignment only through the housing seat. the 172 prefix identifies insert bearings with a STANDARD (non-extended) inner ring; 62 after it gives the sphered-OD ISO 15 dimension series 02 and 63 the series 03, so 1726203 follows the 63-series deep-groove ball envelope with a spherically ground outside surface. the final two digits 03 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 17 mm bore. -2RS1 denotes nitrile contact seals moulded directly into the outer-ring recess on both sides; there is no separate flinger, which suits the standard-inner-ring 172-execution mounted inside a sealed Y-housing. Envelope 17x40x12 mm (0.669x1.575x0.472 in), outer ring 12 mm wide, C 9.56 kN, C0 4.75 kN, Pu 0.2 kN. The catalogue publishes a single speed ceiling, the limiting speed: 12,000 r/min; mass 60 g. Capacity density: 9.56 kN from 0.060 kg of bearing steel is about 159.333 kN per kilogram, and per width millimetre the 12 mm unit carries 0.797 kN of dynamic capacity. Bore-to-OD planning: OD 40 over bore 17 is a 2.353x step, while bore/overall-width gives 1.417; the spherical seat in the matching Y-housing must be specified to the 40 mm OD, not to a cylindrical housing bore. Fillet discipline: the printed r_min 0.6 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 17x40 mm insert on its chamfer tilts the whole spherical seat. Imperial procurement cross-check: 0.669 in bore, 1.575 in OD, 0.472 in overall width; the 60 g mass converts to 0.060 kg (2.1 oz) for the bill of materials. Pitch-diameter arithmetic: dm = (17+40)/2 = 28.5 mm; at the 12,000 r/min limiting speed the ball set runs at dn approx 3.42x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Standard-inner-ring note: unlike YAR/YEL/YSP inserts this 172 execution has NO shaft locking device and NO extended ring — it locates by fits like a normal sealed deep-groove ball bearing, while the sphered outside surface still provides static self-alignment inside the Y-housing. Fit note for 1726203-2RS1: because no locking device exists, shaft and housing fits do the locating work; treat the fit recommendations for sealed deep-groove bearings, and let the spherical OD pivot in the housing rather than forcing axial alignment.", "applications": [ "light conveyor take-ups with standard shaft fits", "small Y-housed fan positions" ], "failure_modes": [ "VP274/B lubrication holes blocked by a misaligned housing groove starve the spherical seat during re-greasing", "shaft fit wrong (no locking device exists): too loose creeps, too tight removes the residual clearance the spherical seat relies on", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "No locking device means shaft preparation is everything for 1726203-2RS1: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "The 17x40 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "Ordering discipline for the 17 mm size: the chapter lists several executions side by side (17262 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726203-2RS1?", "a": "1726203-2RS1 measures 17 mm bore x 40 mm OD x 12 mm overall width (outer ring 12 mm wide), 0.669 x 1.575 x 0.472 in; mass about 60 g. SKF 17000 ratings: C 9.56 kN, C0 4.75 kN, Pu 0.2 kN, limiting speed 12,000 r/min." }, { "q": "What does the designation 1726203-2RS1 mean?", "a": "the 172 prefix identifies insert bearings with a STANDARD (non-extended) inner ring; 62 after it gives the sphered-OD ISO 15 dimension series 02 and 63 the series 03, so 1726203 follows the 63-series deep-groove ball envelope with a spherically ground outside surface. the final two digits 03 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 17 mm bore. -2RS1 denotes nitrile contact seals moulded directly into the outer-ring recess on both sides; there is no separate flinger, which suits the standard-inner-ring 172-execution mounted inside a sealed Y-housing." }, { "q": "What is a 172-series insert bearing?", "a": "It is an insert bearing with a STANDARD-width inner ring (172 prefix) instead of the extended YAR/YEL/YSP rings; the next digits give the sphered-OD ISO 15 dimension series — 62 for series 02 and 63 for series 03. It locks by fits, like a normal sealed deep-groove bearing, not by screws or a collar." }, { "q": "How is axial position secured with no locking device?", "a": "Through the recommended shaft and housing fits, abutments and any snap rings per the catalogue — there are no screws, collar or sleeve. The spherical OD still supplies the static self-alignment in the Y-housing." } ], "cross_ref": [ { "equiv_sku": "6203", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6203 shares the 17x40x12 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6203 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726203-2RS1" ], "locale_variants": {} }, { "sku": "1726204-2RS1", "brand": "SKF", "manufacturer_designation": "1726204-2RS1", "series": "17262-series", "type": "insert", "d_mm": 20, "D_mm": 47, "B_mm": 14, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 12.7, "static_load_kN": 6.55, "fatigue_load_limit_kN": 0.28, "limiting_speed_rpm": 10000, "max_rpm": 10000, "weight_g": 100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The 17262 series order number 1726204-2RS1 is a SKF insert bearing (Y-bearing) for a 20 mm shaft: insert bearing with a standard (non-extended) inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 47 mm. The unit is a capped deep-groove ball bearing to the ISO 15 03 envelope whose outer surface is sphered instead of cylindrical, so it combines a standard fit with Y-housing alignment. reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 04 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 20 mm bore. the -2RS1 suffix is the classic contact NBR seal on each side without add-on flingers — grease retention for life inside the sphered-OD ISO 15 envelope. Envelope 20x47x14 mm (0.787x1.85x0.551 in), outer ring 14 mm wide, C 12.7 kN, C0 6.55 kN, Pu 0.28 kN. The catalogue publishes a single speed ceiling, the limiting speed: 10,000 r/min; mass 100 g. Selection figures for 1726204-2RS1: C0/C is 0.516, Pu 0.28 kN is 2.205 % of the 12.7 kN dynamic rating, and the 100 g catalogue mass works out to roughly 5 g per millimetre of the 20 mm bore. Outer-vs-overall width: the outer ring is 14 mm wide inside the 14 mm total, equal to the overall width because this is the standard-inner-ring execution. Fatigue-limit check: Pu 0.28 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for 1726204-2RS1 — most belt-driven mounted-unit loads sit comfortably under 2.205 % of C. Static-first planning: the 0.468 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 20 mm shaft, not the 12.7 kN L10 value. Imperial procurement cross-check: 0.787 in bore, 1.85 in OD, 0.551 in overall width; the 100 g mass converts to 0.100 kg (3.5 oz) for the bill of materials. Standard-inner-ring note: unlike YAR/YEL/YSP inserts this 172 execution has NO shaft locking device and NO extended ring — it locates by fits like a normal sealed deep-groove ball bearing, while the sphered outside surface still provides static self-alignment inside the Y-housing. Geometry note: with the standard inner ring the 14 mm width and 20x47 mm bore/OD match the 63-series deep-groove ball envelope, while only the sphered outer surface identifies it as a Y-insert.", "applications": [ "light conveyor take-ups with standard shaft fits", "small Y-housed fan positions" ], "failure_modes": [ "shaft fit wrong (no locking device exists): too loose creeps, too tight removes the residual clearance the spherical seat relies on", "VP274/B lubrication holes blocked by a misaligned housing groove starve the spherical seat during re-greasing", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "No locking device means shaft preparation is everything for 1726204-2RS1: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "The 20x47 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "The 12.7/6.55 kN figures belong specifically to 1726204-2RS1; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726204-2RS1?", "a": "Boundary dimensions: bore 20 mm, sphered OD 47 mm, overall width 14 mm; weight 100 g. Loads: dynamic 12.7 kN, static 6.55 kN, fatigue 0.28 kN; the only published speed is the 10,000 r/min limiting value." }, { "q": "What does the designation 1726204-2RS1 mean?", "a": "reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 04 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 20 mm bore. the -2RS1 suffix is the classic contact NBR seal on each side without add-on flingers — grease retention for life inside the sphered-OD ISO 15 envelope." }, { "q": "Is 1726204-2RS1 the same as a 6304 sealed deep-groove bearing?", "a": "The 20x47x14 mm envelope and ratings follow the 63-series plan, but the OUTER surface is spherically ground for a Y-housing; pressing it into a normal cylindrical bore defeats its design. Treat it as an insert, not a drop-in 63-bearing." }, { "q": "What is a 172-series insert bearing?", "a": "It is an insert bearing with a STANDARD-width inner ring (172 prefix) instead of the extended YAR/YEL/YSP rings; the next digits give the sphered-OD ISO 15 dimension series — 62 for series 02 and 63 for series 03. It locks by fits, like a normal sealed deep-groove bearing, not by screws or a collar." } ], "cross_ref": [ { "equiv_sku": "6204", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6204 shares the 20x47x14 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6204 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726204-2RS1" ], "locale_variants": {} }, { "sku": "1726205-2RS1", "brand": "SKF", "manufacturer_designation": "1726205-2RS1", "series": "17262-series", "type": "insert", "d_mm": 25, "D_mm": 52, "B_mm": 15, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14, "static_load_kN": 7.8, "fatigue_load_limit_kN": 0.335, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "1726205-2RS1 is SKF's 25 mm-bore insert bearing with a standard (non-extended) inner ring in the 17262 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 25x52x15 mm. Unlike the extended-ring Y executions this is a standard-width sealed deep-groove ball insert: normal-width inner ring, spherically ground outer ring, static self-alignment only through the housing seat. the 172 prefix identifies insert bearings with a STANDARD (non-extended) inner ring; 62 after it gives the sphered-OD ISO 15 dimension series 02 and 63 the series 03, so 1726205 follows the 63-series deep-groove ball envelope with a spherically ground outside surface. the final two digits 05 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 25 mm bore. -2RS1 denotes nitrile contact seals moulded directly into the outer-ring recess on both sides; there is no separate flinger, which suits the standard-inner-ring 172-execution mounted inside a sealed Y-housing. Envelope 25x52x15 mm (0.984x2.047x0.591 in), outer ring 15 mm wide, C 14 kN, C0 7.8 kN, Pu 0.335 kN. The catalogue publishes a single speed ceiling, the limiting speed: 8,500 r/min; mass 120 g. Rating split for the maintenance file: dynamic 14 kN (L10), static 7.8 kN (s0 shock check), fatigue 0.335 kN (adjusted life) — three separate uses for 1726205-2RS1, none interchangeable with another. Static-first planning: the 0.52 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 25 mm shaft, not the 14 kN L10 value. Pitch-diameter arithmetic: dm = (25+52)/2 = 38.5 mm; at the 8,500 r/min limiting speed the ball set runs at dn approx 3.27x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Imperial procurement cross-check: 0.984 in bore, 2.047 in OD, 0.591 in overall width; the 120 g mass converts to 0.120 kg (4.2 oz) for the bill of materials. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 34.3 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Standard-inner-ring note: unlike YAR/YEL/YSP inserts this 172 execution has NO shaft locking device and NO extended ring — it locates by fits like a normal sealed deep-groove ball bearing, while the sphered outside surface still provides static self-alignment inside the Y-housing. Fit note for 1726205-2RS1: because no locking device exists, shaft and housing fits do the locating work; treat the fit recommendations for sealed deep-groove bearings, and let the spherical OD pivot in the housing rather than forcing axial alignment.", "applications": [ "general machinery using Y-flange and Y-pillow housings", "Y-housing units on standard machined shafts", "fan and conveyor positions ordered as ISO-envelope spares" ], "failure_modes": [ "treated as a normal cylindrical-OD bearing and pressed into a plain bore: the sphered outer surface cannot locate radially without the matching spherical housing seat", "shaft fit wrong (no locking device exists): too loose creeps, too tight removes the residual clearance the spherical seat relies on", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "The 25x52 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "No locking device means shaft preparation is everything for 1726205-2RS1: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "Catalogue ratings belong to 1726205-2RS1 as the standard std rs1 execution; other order numbers of the 1726205 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726205-2RS1?", "a": "1726205-2RS1 measures 25 mm bore x 52 mm OD x 15 mm overall width (outer ring 15 mm wide), 0.984 x 2.047 x 0.591 in; mass about 120 g. SKF 17000 ratings: C 14 kN, C0 7.8 kN, Pu 0.335 kN, limiting speed 8,500 r/min." }, { "q": "What does the designation 1726205-2RS1 mean?", "a": "the 172 prefix identifies insert bearings with a STANDARD (non-extended) inner ring; 62 after it gives the sphered-OD ISO 15 dimension series 02 and 63 the series 03, so 1726205 follows the 63-series deep-groove ball envelope with a spherically ground outside surface. the final two digits 05 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 25 mm bore. -2RS1 denotes nitrile contact seals moulded directly into the outer-ring recess on both sides; there is no separate flinger, which suits the standard-inner-ring 172-execution mounted inside a sealed Y-housing." }, { "q": "What do B and VP274 mean?", "a": "B denotes lubrication holes in the outer ring (only on standard-inner-ring executions); VP274 is the NBR contact-seal package on both sides. The B-2RS1/VP274 article is therefore sealed yet re-lubricatable through the housing." }, { "q": "Is 1726205-2RS1 the same as a 6305 sealed deep-groove bearing?", "a": "The 25x52x15 mm envelope and ratings follow the 63-series plan, but the OUTER surface is spherically ground for a Y-housing; pressing it into a normal cylindrical bore defeats its design. Treat it as an insert, not a drop-in 63-bearing." } ], "cross_ref": [ { "equiv_sku": "6205", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6205 shares the 25x52x15 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6205 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726205-2RS1" ], "locale_variants": {} }, { "sku": "1726305-2RS1", "brand": "SKF", "manufacturer_designation": "1726305-2RS1", "series": "17263-series", "type": "insert", "d_mm": 25, "D_mm": 62, "B_mm": 17, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 22.5, "static_load_kN": 11.6, "fatigue_load_limit_kN": 0.49, "limiting_speed_rpm": 7500, "max_rpm": 7500, "weight_g": 220, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The 17263 series order number 1726305-2RS1 is a SKF insert bearing (Y-bearing) for a 25 mm shaft: insert bearing with a standard (non-extended) inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 62 mm. The unit is a capped deep-groove ball bearing to the ISO 15 03 envelope whose outer surface is sphered instead of cylindrical, so it combines a standard fit with Y-housing alignment. reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 05 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 25 mm bore. the -2RS1 suffix is the classic contact NBR seal on each side without add-on flingers — grease retention for life inside the sphered-OD ISO 15 envelope. Envelope 25x62x17 mm (0.984x2.441x0.669 in), outer ring 17 mm wide, C 22.5 kN, C0 11.6 kN, Pu 0.49 kN. The catalogue publishes a single speed ceiling, the limiting speed: 7,500 r/min; mass 220 g. Envelope arithmetic: the radial section from 25 mm bore to 62 mm OD is 18.5 mm; dividing C 22.5 kN by that section gives 1.216 kN per section millimetre, and the 17 mm overall width is 0.919x the section. Outer-vs-overall width: the outer ring is 17 mm wide inside the 17 mm total, equal to the overall width because this is the standard-inner-ring execution. Bore-to-OD planning: OD 62 over bore 25 is a 2.48x step, while bore/overall-width gives 1.471; the spherical seat in the matching Y-housing must be specified to the 62 mm OD, not to a cylindrical housing bore. Mass-to-load ratio for 1726305-2RS1: 9.778 g of catalogue mass per rated kN of C, and 8.8 g per millimetre of bore — useful when comparing executions of the same 25x62 mm envelope on the drawing. Grease-life arithmetic is dominated by speed: at dn approx 3.26x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Standard-inner-ring note: unlike YAR/YEL/YSP inserts this 172 execution has NO shaft locking device and NO extended ring — it locates by fits like a normal sealed deep-groove ball bearing, while the sphered outside surface still provides static self-alignment inside the Y-housing. Fit note for 1726305-2RS1: because no locking device exists, shaft and housing fits do the locating work; treat the fit recommendations for sealed deep-groove bearings, and let the spherical OD pivot in the housing rather than forcing axial alignment.", "applications": [ "Y-housing units on standard machined shafts", "fan and conveyor positions ordered as ISO-envelope spares", "general machinery using Y-flange and Y-pillow housings" ], "failure_modes": [ "shaft fit wrong (no locking device exists): too loose creeps, too tight removes the residual clearance the spherical seat relies on", "VP274/B lubrication holes blocked by a misaligned housing groove starve the spherical seat during re-greasing", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "No locking device means shaft preparation is everything for 1726305-2RS1: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "The 25x62 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "The 22.5/11.6 kN figures belong specifically to 1726305-2RS1; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726305-2RS1?", "a": "Boundary dimensions: bore 25 mm, sphered OD 62 mm, overall width 17 mm; weight 220 g. Loads: dynamic 22.5 kN, static 11.6 kN, fatigue 0.49 kN; the only published speed is the 7,500 r/min limiting value." }, { "q": "What does the designation 1726305-2RS1 mean?", "a": "reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 05 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 25 mm bore. the -2RS1 suffix is the classic contact NBR seal on each side without add-on flingers — grease retention for life inside the sphered-OD ISO 15 envelope." }, { "q": "Is 1726305-2RS1 the same as a 6305 sealed deep-groove bearing?", "a": "The 25x62x17 mm envelope and ratings follow the 63-series plan, but the OUTER surface is spherically ground for a Y-housing; pressing it into a normal cylindrical bore defeats its design. Treat it as an insert, not a drop-in 63-bearing." }, { "q": "What is a 172-series insert bearing?", "a": "It is an insert bearing with a STANDARD-width inner ring (172 prefix) instead of the extended YAR/YEL/YSP rings; the next digits give the sphered-OD ISO 15 dimension series — 62 for series 02 and 63 for series 03. It locks by fits, like a normal sealed deep-groove bearing, not by screws or a collar." } ], "cross_ref": [ { "equiv_sku": "6305", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6305 shares the 25x62x17 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6305 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726305-2RS1" ], "locale_variants": {} }, { "sku": "1726206-2RS1", "brand": "SKF", "manufacturer_designation": "1726206-2RS1", "series": "17262-series", "type": "insert", "d_mm": 30, "D_mm": 62, "B_mm": 16, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 19.5, "static_load_kN": 11.2, "fatigue_load_limit_kN": 0.475, "limiting_speed_rpm": 7500, "max_rpm": 7500, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "1726206-2RS1 is SKF's 30 mm-bore insert bearing with a standard (non-extended) inner ring in the 17262 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 30x62x16 mm. Unlike the extended-ring Y executions this is a standard-width sealed deep-groove ball insert: normal-width inner ring, spherically ground outer ring, static self-alignment only through the housing seat. the 172 prefix identifies insert bearings with a STANDARD (non-extended) inner ring; 62 after it gives the sphered-OD ISO 15 dimension series 02 and 63 the series 03, so 1726206 follows the 63-series deep-groove ball envelope with a spherically ground outside surface. the final two digits 06 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 30 mm (code 06 x 5) bore. -2RS1 denotes nitrile contact seals moulded directly into the outer-ring recess on both sides; there is no separate flinger, which suits the standard-inner-ring 172-execution mounted inside a sealed Y-housing. Envelope 30x62x16 mm (1.181x2.441x0.63 in), outer ring 16 mm wide, C 19.5 kN, C0 11.2 kN, Pu 0.475 kN. The catalogue publishes a single speed ceiling, the limiting speed: 7,500 r/min; mass 190 g. Bore-to-OD planning: OD 62 over bore 30 is a 2.067x step, while bore/overall-width gives 1.875; the spherical seat in the matching Y-housing must be specified to the 62 mm OD, not to a cylindrical housing bore. Rating split for the maintenance file: dynamic 19.5 kN (L10), static 11.2 kN (s0 shock check), fatigue 0.475 kN (adjusted life) — three separate uses for 1726206-2RS1, none interchangeable with another. Imperial procurement cross-check: 1.181 in bore, 2.441 in OD, 0.63 in overall width; the 190 g mass converts to 0.190 kg (6.7 oz) for the bill of materials. Fillet discipline: the printed r_min 1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 30x62 mm insert on its chamfer tilts the whole spherical seat. Selection figures for 1726206-2RS1: C0/C is 0.574, Pu 0.475 kN is 2.436 % of the 19.5 kN dynamic rating, and the 190 g catalogue mass works out to roughly 6.333 g per millimetre of the 30 mm bore. Standard-inner-ring note: unlike YAR/YEL/YSP inserts this 172 execution has NO shaft locking device and NO extended ring — it locates by fits like a normal sealed deep-groove ball bearing, while the sphered outside surface still provides static self-alignment inside the Y-housing. Fit note for 1726206-2RS1: because no locking device exists, shaft and housing fits do the locating work; treat the fit recommendations for sealed deep-groove bearings, and let the spherical OD pivot in the housing rather than forcing axial alignment.", "applications": [ "Y-housing units on standard machined shafts", "general machinery using Y-flange and Y-pillow housings", "fan and conveyor positions ordered as ISO-envelope spares" ], "failure_modes": [ "treated as a normal cylindrical-OD bearing and pressed into a plain bore: the sphered outer surface cannot locate radially without the matching spherical housing seat", "shaft fit wrong (no locking device exists): too loose creeps, too tight removes the residual clearance the spherical seat relies on", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "The 30x62 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "No locking device means shaft preparation is everything for 1726206-2RS1: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "Catalogue ratings belong to 1726206-2RS1 as the standard std rs1 execution; other order numbers of the 1726206 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726206-2RS1?", "a": "1726206-2RS1 measures 30 mm bore x 62 mm OD x 16 mm overall width (outer ring 16 mm wide), 1.181 x 2.441 x 0.63 in; mass about 190 g. SKF 17000 ratings: C 19.5 kN, C0 11.2 kN, Pu 0.475 kN, limiting speed 7,500 r/min." }, { "q": "What does the designation 1726206-2RS1 mean?", "a": "the 172 prefix identifies insert bearings with a STANDARD (non-extended) inner ring; 62 after it gives the sphered-OD ISO 15 dimension series 02 and 63 the series 03, so 1726206 follows the 63-series deep-groove ball envelope with a spherically ground outside surface. the final two digits 06 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 30 mm (code 06 x 5) bore. -2RS1 denotes nitrile contact seals moulded directly into the outer-ring recess on both sides; there is no separate flinger, which suits the standard-inner-ring 172-execution mounted inside a sealed Y-housing." }, { "q": "How is axial position secured with no locking device?", "a": "Through the recommended shaft and housing fits, abutments and any snap rings per the catalogue — there are no screws, collar or sleeve. The spherical OD still supplies the static self-alignment in the Y-housing." }, { "q": "What do B and VP274 mean?", "a": "B denotes lubrication holes in the outer ring (only on standard-inner-ring executions); VP274 is the NBR contact-seal package on both sides. The B-2RS1/VP274 article is therefore sealed yet re-lubricatable through the housing." } ], "cross_ref": [ { "equiv_sku": "6206", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6206 shares the 30x62x16 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6206 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726206-2RS1" ], "locale_variants": {} }, { "sku": "1726306-2RS1", "brand": "SKF", "manufacturer_designation": "1726306-2RS1", "series": "17263-series", "type": "insert", "d_mm": 30, "D_mm": 72, "B_mm": 19, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 28.1, "static_load_kN": 16, "fatigue_load_limit_kN": 0.67, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 340, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "1726306-2RS1 is SKF's 30 mm-bore insert bearing with a standard (non-extended) inner ring in the 17263 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 30x72x19 mm. Unlike the extended-ring Y executions this is a standard-width sealed deep-groove ball insert: normal-width inner ring, spherically ground outer ring, static self-alignment only through the housing seat. the 172 prefix identifies insert bearings with a STANDARD (non-extended) inner ring; 62 after it gives the sphered-OD ISO 15 dimension series 02 and 63 the series 03, so 1726306 follows the 63-series deep-groove ball envelope with a spherically ground outside surface. the final two digits 06 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 30 mm (code 06 x 5) bore. -2RS1 denotes nitrile contact seals moulded directly into the outer-ring recess on both sides; there is no separate flinger, which suits the standard-inner-ring 172-execution mounted inside a sealed Y-housing. Envelope 30x72x19 mm (1.181x2.835x0.748 in), outer ring 19 mm wide, C 28.1 kN, C0 16 kN, Pu 0.67 kN. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 340 g. Spherical-seat note in numbers: the 72 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 51 = 160.221 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fillet discipline: the printed r_min 1.1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 30x72 mm insert on its chamfer tilts the whole spherical seat. Grease-life arithmetic is dominated by speed: at dn approx 3.21x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Mass-to-load ratio for 1726306-2RS1: 12.1 g of catalogue mass per rated kN of C, and 11.333 g per millimetre of bore — useful when comparing executions of the same 30x72 mm envelope on the drawing. Fatigue-limit check: Pu 0.67 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for 1726306-2RS1 — most belt-driven mounted-unit loads sit comfortably under 2.384 % of C. Standard-inner-ring note: unlike YAR/YEL/YSP inserts this 172 execution has NO shaft locking device and NO extended ring — it locates by fits like a normal sealed deep-groove ball bearing, while the sphered outside surface still provides static self-alignment inside the Y-housing. Geometry note: with the standard inner ring the 19 mm width and 30x72 mm bore/OD match the 63-series deep-groove ball envelope, while only the sphered outer surface identifies it as a Y-insert.", "applications": [ "general machinery using Y-flange and Y-pillow housings", "Y-housing units on standard machined shafts", "fan and conveyor positions ordered as ISO-envelope spares" ], "failure_modes": [ "treated as a normal cylindrical-OD bearing and pressed into a plain bore: the sphered outer surface cannot locate radially without the matching spherical housing seat", "shaft fit wrong (no locking device exists): too loose creeps, too tight removes the residual clearance the spherical seat relies on", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The 30x72 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "No locking device means shaft preparation is everything for 1726306-2RS1: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "Catalogue ratings belong to 1726306-2RS1 as the standard std rs1 execution; other order numbers of the 1726306 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726306-2RS1?", "a": "1726306-2RS1 measures 30 mm bore x 72 mm OD x 19 mm overall width (outer ring 19 mm wide), 1.181 x 2.835 x 0.748 in; mass about 340 g. SKF 17000 ratings: C 28.1 kN, C0 16 kN, Pu 0.67 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation 1726306-2RS1 mean?", "a": "the 172 prefix identifies insert bearings with a STANDARD (non-extended) inner ring; 62 after it gives the sphered-OD ISO 15 dimension series 02 and 63 the series 03, so 1726306 follows the 63-series deep-groove ball envelope with a spherically ground outside surface. the final two digits 06 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 30 mm (code 06 x 5) bore. -2RS1 denotes nitrile contact seals moulded directly into the outer-ring recess on both sides; there is no separate flinger, which suits the standard-inner-ring 172-execution mounted inside a sealed Y-housing." }, { "q": "What is a 172-series insert bearing?", "a": "It is an insert bearing with a STANDARD-width inner ring (172 prefix) instead of the extended YAR/YEL/YSP rings; the next digits give the sphered-OD ISO 15 dimension series — 62 for series 02 and 63 for series 03. It locks by fits, like a normal sealed deep-groove bearing, not by screws or a collar." }, { "q": "How is axial position secured with no locking device?", "a": "Through the recommended shaft and housing fits, abutments and any snap rings per the catalogue — there are no screws, collar or sleeve. The spherical OD still supplies the static self-alignment in the Y-housing." } ], "cross_ref": [ { "equiv_sku": "6306", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6306 shares the 30x72x19 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6306 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726306-2RS1" ], "locale_variants": {} }, { "sku": "1726207-2RS1", "brand": "SKF", "manufacturer_designation": "1726207-2RS1", "series": "17262-series", "type": "insert", "d_mm": 35, "D_mm": 72, "B_mm": 17, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 25.5, "static_load_kN": 15.3, "fatigue_load_limit_kN": 0.655, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 280, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "1726207-2RS1 is SKF's 35 mm-bore insert bearing with a standard (non-extended) inner ring in the 17262 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 35x72x17 mm. Unlike the extended-ring Y executions this is a standard-width sealed deep-groove ball insert: normal-width inner ring, spherically ground outer ring, static self-alignment only through the housing seat. the 172 prefix identifies insert bearings with a STANDARD (non-extended) inner ring; 62 after it gives the sphered-OD ISO 15 dimension series 02 and 63 the series 03, so 1726207 follows the 63-series deep-groove ball envelope with a spherically ground outside surface. the final two digits 07 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 35 mm (code 07 x 5) bore. -2RS1 denotes nitrile contact seals moulded directly into the outer-ring recess on both sides; there is no separate flinger, which suits the standard-inner-ring 172-execution mounted inside a sealed Y-housing. Envelope 35x72x17 mm (1.378x2.835x0.669 in), outer ring 17 mm wide, C 25.5 kN, C0 15.3 kN, Pu 0.655 kN. The catalogue publishes a single speed ceiling, the limiting speed: 6,300 r/min; mass 280 g. Mass-to-load ratio for 1726207-2RS1: 10.98 g of catalogue mass per rated kN of C, and 8 g per millimetre of bore — useful when comparing executions of the same 35x72 mm envelope on the drawing. Width accounting on this execution: 17 mm overall and 17 mm outer-ring width leave the housing designer 0 mm of inner-ring projection to accommodate the locking arrangement. Envelope arithmetic: the radial section from 35 mm bore to 72 mm OD is 18.5 mm; dividing C 25.5 kN by that section gives 1.378 kN per section millimetre, and the 17 mm overall width is 0.919x the section. Load balance for documentation: C0 15.3 kN against C 25.5 kN gives a 0.6 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Rating split for the maintenance file: dynamic 25.5 kN (L10), static 15.3 kN (s0 shock check), fatigue 0.655 kN (adjusted life) — three separate uses for 1726207-2RS1, none interchangeable with another. Standard-inner-ring note: unlike YAR/YEL/YSP inserts this 172 execution has NO shaft locking device and NO extended ring — it locates by fits like a normal sealed deep-groove ball bearing, while the sphered outside surface still provides static self-alignment inside the Y-housing. Geometry note: with the standard inner ring the 17 mm width and 35x72 mm bore/OD match the 63-series deep-groove ball envelope, while only the sphered outer surface identifies it as a Y-insert.", "applications": [ "fan and conveyor positions ordered as ISO-envelope spares", "general machinery using Y-flange and Y-pillow housings", "Y-housing units on standard machined shafts" ], "failure_modes": [ "VP274/B lubrication holes blocked by a misaligned housing groove starve the spherical seat during re-greasing", "shaft fit wrong (no locking device exists): too loose creeps, too tight removes the residual clearance the spherical seat relies on", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "The 35x72 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "No locking device means shaft preparation is everything for 1726207-2RS1: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "Ordering discipline for the 35 mm size: the chapter lists several executions side by side (17262 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726207-2RS1?", "a": "1726207-2RS1 measures 35 mm bore x 72 mm OD x 17 mm overall width (outer ring 17 mm wide), 1.378 x 2.835 x 0.669 in; mass about 280 g. SKF 17000 ratings: C 25.5 kN, C0 15.3 kN, Pu 0.655 kN, limiting speed 6,300 r/min." }, { "q": "What does the designation 1726207-2RS1 mean?", "a": "the 172 prefix identifies insert bearings with a STANDARD (non-extended) inner ring; 62 after it gives the sphered-OD ISO 15 dimension series 02 and 63 the series 03, so 1726207 follows the 63-series deep-groove ball envelope with a spherically ground outside surface. the final two digits 07 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 35 mm (code 07 x 5) bore. -2RS1 denotes nitrile contact seals moulded directly into the outer-ring recess on both sides; there is no separate flinger, which suits the standard-inner-ring 172-execution mounted inside a sealed Y-housing." }, { "q": "What is a 172-series insert bearing?", "a": "It is an insert bearing with a STANDARD-width inner ring (172 prefix) instead of the extended YAR/YEL/YSP rings; the next digits give the sphered-OD ISO 15 dimension series — 62 for series 02 and 63 for series 03. It locks by fits, like a normal sealed deep-groove bearing, not by screws or a collar." }, { "q": "How is axial position secured with no locking device?", "a": "Through the recommended shaft and housing fits, abutments and any snap rings per the catalogue — there are no screws, collar or sleeve. The spherical OD still supplies the static self-alignment in the Y-housing." } ], "cross_ref": [ { "equiv_sku": "6207", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6207 shares the 35x72x17 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6207 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726207-2RS1" ], "locale_variants": {} }, { "sku": "1726307-2RS1", "brand": "SKF", "manufacturer_designation": "1726307-2RS1", "series": "17263-series", "type": "insert", "d_mm": 35, "D_mm": 80, "B_mm": 21, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 19, "fatigue_load_limit_kN": 0.815, "limiting_speed_rpm": 6000, "max_rpm": 6000, "weight_g": 440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The 17263 series order number 1726307-2RS1 is a SKF insert bearing (Y-bearing) for a 35 mm shaft: insert bearing with a standard (non-extended) inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 80 mm. The unit is a capped deep-groove ball bearing to the ISO 15 03 envelope whose outer surface is sphered instead of cylindrical, so it combines a standard fit with Y-housing alignment. reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 07 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 35 mm (code 07 x 5) bore. the -2RS1 suffix is the classic contact NBR seal on each side without add-on flingers — grease retention for life inside the sphered-OD ISO 15 envelope. Envelope 35x80x21 mm (1.378x3.15x0.827 in), outer ring 21 mm wide, C 33.2 kN, C0 19 kN, Pu 0.815 kN. The catalogue publishes a single speed ceiling, the limiting speed: 6,000 r/min; mass 440 g. Speed ceiling of 6,000 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Fatigue-limit check: Pu 0.815 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for 1726307-2RS1 — most belt-driven mounted-unit loads sit comfortably under 2.455 % of C. Selection figures for 1726307-2RS1: C0/C is 0.572, Pu 0.815 kN is 2.455 % of the 33.2 kN dynamic rating, and the 440 g catalogue mass works out to roughly 12.571 g per millimetre of the 35 mm bore. Mounting verification on 1726307-2RS1 uses the printed catalogue procedure rather than torque guessing. At the printed limiting speed of 6,000 r/min the mean diameter dm = 57.5 mm implies dn about 3.45x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Standard-inner-ring note: unlike YAR/YEL/YSP inserts this 172 execution has NO shaft locking device and NO extended ring — it locates by fits like a normal sealed deep-groove ball bearing, while the sphered outside surface still provides static self-alignment inside the Y-housing. Geometry note: with the standard inner ring the 21 mm width and 35x80 mm bore/OD match the 63-series deep-groove ball envelope, while only the sphered outer surface identifies it as a Y-insert.", "applications": [ "fan and conveyor positions ordered as ISO-envelope spares", "Y-housing units on standard machined shafts", "general machinery using Y-flange and Y-pillow housings" ], "failure_modes": [ "VP274/B lubrication holes blocked by a misaligned housing groove starve the spherical seat during re-greasing", "treated as a normal cylindrical-OD bearing and pressed into a plain bore: the sphered outer surface cannot locate radially without the matching spherical housing seat", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "The 35x80 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "No locking device means shaft preparation is everything for 1726307-2RS1: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "Ordering discipline for the 35 mm size: the chapter lists several executions side by side (17263 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726307-2RS1?", "a": "Boundary dimensions: bore 35 mm, sphered OD 80 mm, overall width 21 mm; weight 440 g. Loads: dynamic 33.2 kN, static 19 kN, fatigue 0.815 kN; the only published speed is the 6,000 r/min limiting value." }, { "q": "What does the designation 1726307-2RS1 mean?", "a": "reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 07 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 35 mm (code 07 x 5) bore. the -2RS1 suffix is the classic contact NBR seal on each side without add-on flingers — grease retention for life inside the sphered-OD ISO 15 envelope." }, { "q": "How is axial position secured with no locking device?", "a": "Through the recommended shaft and housing fits, abutments and any snap rings per the catalogue — there are no screws, collar or sleeve. The spherical OD still supplies the static self-alignment in the Y-housing." }, { "q": "What do B and VP274 mean?", "a": "B denotes lubrication holes in the outer ring (only on standard-inner-ring executions); VP274 is the NBR contact-seal package on both sides. The B-2RS1/VP274 article is therefore sealed yet re-lubricatable through the housing." } ], "cross_ref": [ { "equiv_sku": "6307", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6307 shares the 35x80x21 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6307 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726307-2RS1" ], "locale_variants": {} }, { "sku": "1726208-2RS1", "brand": "SKF", "manufacturer_designation": "1726208-2RS1", "series": "17262-series", "type": "insert", "d_mm": 40, "D_mm": 80, "B_mm": 18, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.7, "static_load_kN": 19, "fatigue_load_limit_kN": 0.8, "limiting_speed_rpm": 5600, "max_rpm": 5600, "weight_g": 350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, 1726208-2RS1 is a insert bearing with a standard (non-extended) inner ring, 40x80x18 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction is the 172-family compromise: 63-series ball geometry and standard inner ring width, contact-sealed both sides, with the convex spherical OD that makes it an insert. 1726208 belongs to the 172 family: deep-groove ball geometry to the ISO 15 03 envelope, but the outer ring OD is sphered rather than cylindrical so it pivots inside the matching housing bore. the final two digits 08 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 40 mm (code 08 x 5) bore. -2RS1 contact seals both sides shield the standard-width inner ring; exclusion comes from the lip itself plus whatever the housing provides. Envelope 40x80x18 mm (1.575x3.15x0.709 in), outer ring 18 mm wide, C 30.7 kN, C0 19 kN, Pu 0.8 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,600 r/min; mass 350 g. Static-first planning: the 1.056 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 40 mm shaft, not the 30.7 kN L10 value. Width accounting on this execution: 18 mm overall and 18 mm outer-ring width leave the housing designer 0 mm of inner-ring projection to accommodate the locking arrangement. Spherical-seat note in numbers: the 80 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 60 = 188.496 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fillet discipline: the printed r_min 1.1 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 40x80 mm insert on its chamfer tilts the whole spherical seat. Grease-life arithmetic is dominated by speed: at dn approx 3.36x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Standard-inner-ring note: unlike YAR/YEL/YSP inserts this 172 execution has NO shaft locking device and NO extended ring — it locates by fits like a normal sealed deep-groove ball bearing, while the sphered outside surface still provides static self-alignment inside the Y-housing. Fit note for 1726208-2RS1: because no locking device exists, shaft and housing fits do the locating work; treat the fit recommendations for sealed deep-groove bearings, and let the spherical OD pivot in the housing rather than forcing axial alignment.", "applications": [ "Y-housing units on standard machined shafts", "fan and conveyor positions ordered as ISO-envelope spares", "general machinery using Y-flange and Y-pillow housings" ], "failure_modes": [ "VP274/B lubrication holes blocked by a misaligned housing groove starve the spherical seat during re-greasing", "treated as a normal cylindrical-OD bearing and pressed into a plain bore: the sphered outer surface cannot locate radially without the matching spherical housing seat", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "The 40x80 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "No locking device means shaft preparation is everything for 1726208-2RS1: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "Ordering discipline for the 40 mm size: the chapter lists several executions side by side (17262 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726208-2RS1?", "a": "The catalogue envelope is 40x80x18 mm with a spherical outside surface; mass 350 g. Ratings C 30.7/19 kN, Pu 0.8 kN, limiting speed 5,600 r/min." }, { "q": "What does the designation 1726208-2RS1 mean?", "a": "1726208 belongs to the 172 family: deep-groove ball geometry to the ISO 15 03 envelope, but the outer ring OD is sphered rather than cylindrical so it pivots inside the matching housing bore. the final two digits 08 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 40 mm (code 08 x 5) bore. -2RS1 contact seals both sides shield the standard-width inner ring; exclusion comes from the lip itself plus whatever the housing provides." }, { "q": "Is 1726208-2RS1 the same as a 6308 sealed deep-groove bearing?", "a": "The 40x80x18 mm envelope and ratings follow the 63-series plan, but the OUTER surface is spherically ground for a Y-housing; pressing it into a normal cylindrical bore defeats its design. Treat it as an insert, not a drop-in 63-bearing." }, { "q": "What is a 172-series insert bearing?", "a": "It is an insert bearing with a STANDARD-width inner ring (172 prefix) instead of the extended YAR/YEL/YSP rings; the next digits give the sphered-OD ISO 15 dimension series — 62 for series 02 and 63 for series 03. It locks by fits, like a normal sealed deep-groove bearing, not by screws or a collar." } ], "cross_ref": [ { "equiv_sku": "6208", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6208 shares the 40x80x18 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6208 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726208-2RS1" ], "locale_variants": {} }, { "sku": "1726308-2RS1", "brand": "SKF", "manufacturer_designation": "1726308-2RS1", "series": "17263-series", "type": "insert", "d_mm": 40, "D_mm": 90, "B_mm": 23, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 41, "static_load_kN": 24, "fatigue_load_limit_kN": 1, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 610, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "1726308-2RS1 is SKF's 40 mm-bore insert bearing with a standard (non-extended) inner ring in the 17263 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 40x90x23 mm. Unlike the extended-ring Y executions this is a standard-width sealed deep-groove ball insert: normal-width inner ring, spherically ground outer ring, static self-alignment only through the housing seat. the 172 prefix identifies insert bearings with a STANDARD (non-extended) inner ring; 62 after it gives the sphered-OD ISO 15 dimension series 02 and 63 the series 03, so 1726308 follows the 63-series deep-groove ball envelope with a spherically ground outside surface. the final two digits 08 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 40 mm (code 08 x 5) bore. -2RS1 denotes nitrile contact seals moulded directly into the outer-ring recess on both sides; there is no separate flinger, which suits the standard-inner-ring 172-execution mounted inside a sealed Y-housing. Envelope 40x90x23 mm (1.575x3.543x0.906 in), outer ring 23 mm wide, C 41 kN, C0 24 kN, Pu 1 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,000 r/min; mass 610 g. Bore-to-OD planning: OD 90 over bore 40 is a 2.25x step, while bore/overall-width gives 1.739; the spherical seat in the matching Y-housing must be specified to the 90 mm OD, not to a cylindrical housing bore. Mounting verification on 1726308-2RS1 uses the printed catalogue procedure rather than torque guessing. Grease-life arithmetic is dominated by speed: at dn approx 3.25x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Mass-to-load ratio for 1726308-2RS1: 14.878 g of catalogue mass per rated kN of C, and 15.25 g per millimetre of bore — useful when comparing executions of the same 40x90 mm envelope on the drawing. Selection figures for 1726308-2RS1: C0/C is 0.585, Pu 1 kN is 2.439 % of the 41 kN dynamic rating, and the 610 g catalogue mass works out to roughly 15.25 g per millimetre of the 40 mm bore. Standard-inner-ring note: unlike YAR/YEL/YSP inserts this 172 execution has NO shaft locking device and NO extended ring — it locates by fits like a normal sealed deep-groove ball bearing, while the sphered outside surface still provides static self-alignment inside the Y-housing. Geometry note: with the standard inner ring the 23 mm width and 40x90 mm bore/OD match the 63-series deep-groove ball envelope, while only the sphered outer surface identifies it as a Y-insert.", "applications": [ "fan and conveyor positions ordered as ISO-envelope spares", "general machinery using Y-flange and Y-pillow housings", "Y-housing units on standard machined shafts" ], "failure_modes": [ "VP274/B lubrication holes blocked by a misaligned housing groove starve the spherical seat during re-greasing", "shaft fit wrong (no locking device exists): too loose creeps, too tight removes the residual clearance the spherical seat relies on", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "The 40x90 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "No locking device means shaft preparation is everything for 1726308-2RS1: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "Ordering discipline for the 40 mm size: the chapter lists several executions side by side (17263 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726308-2RS1?", "a": "1726308-2RS1 measures 40 mm bore x 90 mm OD x 23 mm overall width (outer ring 23 mm wide), 1.575 x 3.543 x 0.906 in; mass about 610 g. SKF 17000 ratings: C 41 kN, C0 24 kN, Pu 1 kN, limiting speed 5,000 r/min." }, { "q": "What does the designation 1726308-2RS1 mean?", "a": "the 172 prefix identifies insert bearings with a STANDARD (non-extended) inner ring; 62 after it gives the sphered-OD ISO 15 dimension series 02 and 63 the series 03, so 1726308 follows the 63-series deep-groove ball envelope with a spherically ground outside surface. the final two digits 08 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 40 mm (code 08 x 5) bore. -2RS1 denotes nitrile contact seals moulded directly into the outer-ring recess on both sides; there is no separate flinger, which suits the standard-inner-ring 172-execution mounted inside a sealed Y-housing." }, { "q": "What do B and VP274 mean?", "a": "B denotes lubrication holes in the outer ring (only on standard-inner-ring executions); VP274 is the NBR contact-seal package on both sides. The B-2RS1/VP274 article is therefore sealed yet re-lubricatable through the housing." }, { "q": "Is 1726308-2RS1 the same as a 6308 sealed deep-groove bearing?", "a": "The 40x90x23 mm envelope and ratings follow the 63-series plan, but the OUTER surface is spherically ground for a Y-housing; pressing it into a normal cylindrical bore defeats its design. Treat it as an insert, not a drop-in 63-bearing." } ], "cross_ref": [ { "equiv_sku": "6308", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6308 shares the 40x90x23 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6308 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726308-2RS1" ], "locale_variants": {} }, { "sku": "1726209-B-2RS1-VP274", "brand": "SKF", "manufacturer_designation": "1726209B-2RS1/VP274", "series": "17262-series", "type": "insert", "d_mm": 45, "D_mm": 85, "B_mm": 19, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 390, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Listed in SKF 17000 chapter 2, 1726209B-2RS1/VP274 is a insert bearing with a standard (non-extended) inner ring, 45x85x19 mm overall, whose convex spherical outer ring pivots in the spherical bore of a Y-pillow, Y-flange or take-up housing. Construction is the 172-family compromise: 63-series ball geometry and standard inner ring width, contact-sealed both sides, with the convex spherical OD that makes it an insert. 1726209 belongs to the 172 family: deep-groove ball geometry to the ISO 15 03 envelope, but the outer ring OD is sphered rather than cylindrical so it pivots inside the matching housing bore. the final two digits 09 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 45 mm (code 09 x 5) bore. VP274 supplies two-side NBR contact sealing for the B (lubrication-hole) execution; the holes let fresh grease reach the sphered-OD seat during servicing. Envelope 45x85x19 mm (1.772x3.346x0.748 in), outer ring 19 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 390 g. Rating split for the maintenance file: dynamic 33.2 kN (L10), static 21.6 kN (s0 shock check), fatigue 0.915 kN (adjusted life) — three separate uses for 1726209B-2RS1/VP274, none interchangeable with another. Spherical-seat note in numbers: the 85 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 65 = 204.204 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Pitch-diameter arithmetic: dm = (45+85)/2 = 65 mm; at the 4,300 r/min limiting speed the ball set runs at dn approx 2.79x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Mounting verification on 1726209-B-2RS1-VP274 uses the printed catalogue procedure rather than torque guessing. At the printed limiting speed of 4,300 r/min the mean diameter dm = 65 mm implies dn about 2.79x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Lubrication-hole note: the B execution carries outer-ring lubrication holes feeding the sphered outside surface; align the hole with the housing groove before clamping the cap, because a hole sealed off by a misaligned housing traps old grease and starves the spherical seat during re-lubrication. Fit note for 1726209-B-2RS1-VP274: because no locking device exists, shaft and housing fits do the locating work; treat the fit recommendations for sealed deep-groove bearings, and let the spherical OD pivot in the housing rather than forcing axial alignment.", "applications": [ "fan and conveyor positions ordered as ISO-envelope spares", "general machinery using Y-flange and Y-pillow housings", "Y-housing units on standard machined shafts" ], "failure_modes": [ "shaft fit wrong (no locking device exists): too loose creeps, too tight removes the residual clearance the spherical seat relies on", "treated as a normal cylindrical-OD bearing and pressed into a plain bore: the sphered outer surface cannot locate radially without the matching spherical housing seat", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "No locking device means shaft preparation is everything for 1726209-B-2RS1-VP274: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "The 45x85 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "The 33.2/21.6 kN figures belong specifically to 1726209B-2RS1/VP274; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726209-B-2RS1-VP274?", "a": "The catalogue envelope is 45x85x19 mm with a spherical outside surface; mass 390 g. Ratings C 33.2/21.6 kN, Pu 0.915 kN, limiting speed 4,300 r/min." }, { "q": "What does the designation 1726209B-2RS1/VP274 mean?", "a": "1726209 belongs to the 172 family: deep-groove ball geometry to the ISO 15 03 envelope, but the outer ring OD is sphered rather than cylindrical so it pivots inside the matching housing bore. the final two digits 09 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 45 mm (code 09 x 5) bore. VP274 supplies two-side NBR contact sealing for the B (lubrication-hole) execution; the holes let fresh grease reach the sphered-OD seat during servicing." }, { "q": "What do B and VP274 mean?", "a": "B denotes lubrication holes in the outer ring (only on standard-inner-ring executions); VP274 is the NBR contact-seal package on both sides. The B-2RS1/VP274 article is therefore sealed yet re-lubricatable through the housing." }, { "q": "Is 1726209-B-2RS1-VP274 the same as a 6309 sealed deep-groove bearing?", "a": "The 45x85x19 mm envelope and ratings follow the 63-series plan, but the OUTER surface is spherically ground for a Y-housing; pressing it into a normal cylindrical bore defeats its design. Treat it as an insert, not a drop-in 63-bearing." } ], "cross_ref": [ { "equiv_sku": "1726209-2RS1", "equiv_brand": "SKF", "level": "full", "note": "Same 45x85x19 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; 1726209-2RS1 is the standard inner ring, fit-located execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "6209", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6209 shares the 45x85x19 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6209 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726209-B-2RS1-VP274", "1726209B-2RS1/VP274" ], "locale_variants": {} }, { "sku": "1726209-2RS1", "brand": "SKF", "manufacturer_designation": "1726209-2RS1", "series": "17262-series", "type": "insert", "d_mm": 45, "D_mm": 85, "B_mm": 19, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 21.6, "fatigue_load_limit_kN": 0.915, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "1726209-2RS1 is SKF's 45 mm-bore insert bearing with a standard (non-extended) inner ring in the 17262 series — a Y-bearing with a spherically ground outside surface for static self-alignment inside a matching SKF Y-housing, boundary dimensions 45x85x19 mm. Unlike the extended-ring Y executions this is a standard-width sealed deep-groove ball insert: normal-width inner ring, spherically ground outer ring, static self-alignment only through the housing seat. the 172 prefix identifies insert bearings with a STANDARD (non-extended) inner ring; 62 after it gives the sphered-OD ISO 15 dimension series 02 and 63 the series 03, so 1726209 follows the 63-series deep-groove ball envelope with a spherically ground outside surface. the final two digits 09 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 45 mm (code 09 x 5) bore. -2RS1 denotes nitrile contact seals moulded directly into the outer-ring recess on both sides; there is no separate flinger, which suits the standard-inner-ring 172-execution mounted inside a sealed Y-housing. Envelope 45x85x19 mm (1.772x3.346x0.748 in), outer ring 19 mm wide, C 33.2 kN, C0 21.6 kN, Pu 0.915 kN. The catalogue publishes a single speed ceiling, the limiting speed: 5,000 r/min; mass 400 g. Selection figures for 1726209-2RS1: C0/C is 0.651, Pu 0.915 kN is 2.756 % of the 33.2 kN dynamic rating, and the 400 g catalogue mass works out to roughly 8.889 g per millimetre of the 45 mm bore. Mounting verification on 1726209-2RS1 uses the printed catalogue procedure rather than torque guessing. Static-first planning: the 1.137 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 45 mm shaft, not the 33.2 kN L10 value. Spherical-seat note in numbers: the 85 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 65 = 204.204 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fatigue-limit check: Pu 0.915 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for 1726209-2RS1 — most belt-driven mounted-unit loads sit comfortably under 2.756 % of C. Standard-inner-ring note: unlike YAR/YEL/YSP inserts this 172 execution has NO shaft locking device and NO extended ring — it locates by fits like a normal sealed deep-groove ball bearing, while the sphered outside surface still provides static self-alignment inside the Y-housing. Fit note for 1726209-2RS1: because no locking device exists, shaft and housing fits do the locating work; treat the fit recommendations for sealed deep-groove bearings, and let the spherical OD pivot in the housing rather than forcing axial alignment.", "applications": [ "general machinery using Y-flange and Y-pillow housings", "Y-housing units on standard machined shafts", "fan and conveyor positions ordered as ISO-envelope spares" ], "failure_modes": [ "VP274/B lubrication holes blocked by a misaligned housing groove starve the spherical seat during re-greasing", "shaft fit wrong (no locking device exists): too loose creeps, too tight removes the residual clearance the spherical seat relies on", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess" ], "pitfalls": [ "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "No locking device means shaft preparation is everything for 1726209-2RS1: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "The 45x85 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "Ordering discipline for the 45 mm size: the chapter lists several executions side by side (17262 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726209-2RS1?", "a": "1726209-2RS1 measures 45 mm bore x 85 mm OD x 19 mm overall width (outer ring 19 mm wide), 1.772 x 3.346 x 0.748 in; mass about 400 g. SKF 17000 ratings: C 33.2 kN, C0 21.6 kN, Pu 0.915 kN, limiting speed 5,000 r/min." }, { "q": "What does the designation 1726209-2RS1 mean?", "a": "the 172 prefix identifies insert bearings with a STANDARD (non-extended) inner ring; 62 after it gives the sphered-OD ISO 15 dimension series 02 and 63 the series 03, so 1726209 follows the 63-series deep-groove ball envelope with a spherically ground outside surface. the final two digits 09 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 45 mm (code 09 x 5) bore. -2RS1 denotes nitrile contact seals moulded directly into the outer-ring recess on both sides; there is no separate flinger, which suits the standard-inner-ring 172-execution mounted inside a sealed Y-housing." }, { "q": "What do B and VP274 mean?", "a": "B denotes lubrication holes in the outer ring (only on standard-inner-ring executions); VP274 is the NBR contact-seal package on both sides. The B-2RS1/VP274 article is therefore sealed yet re-lubricatable through the housing." }, { "q": "Is 1726209-2RS1 the same as a 6309 sealed deep-groove bearing?", "a": "The 45x85x19 mm envelope and ratings follow the 63-series plan, but the OUTER surface is spherically ground for a Y-housing; pressing it into a normal cylindrical bore defeats its design. Treat it as an insert, not a drop-in 63-bearing." } ], "cross_ref": [ { "equiv_sku": "1726209-B-2RS1-VP274", "equiv_brand": "SKF", "level": "full", "note": "Same 45x85x19 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; 1726209B-2RS1/VP274 is the standard inner ring, fit-located execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "6209", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6209 shares the 45x85x19 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6209 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726209-2RS1" ], "locale_variants": {} }, { "sku": "1726309-2RS1", "brand": "SKF", "manufacturer_designation": "1726309-2RS1", "series": "17263-series", "type": "insert", "d_mm": 45, "D_mm": 100, "B_mm": 25, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 31.5, "fatigue_load_limit_kN": 1.34, "limiting_speed_rpm": 4500, "max_rpm": 4500, "weight_g": 800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The 17263 series order number 1726309-2RS1 is a SKF insert bearing (Y-bearing) for a 45 mm shaft: insert bearing with a standard (non-extended) inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 100 mm. The unit is a capped deep-groove ball bearing to the ISO 15 03 envelope whose outer surface is sphered instead of cylindrical, so it combines a standard fit with Y-housing alignment. reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 09 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 45 mm (code 09 x 5) bore. the -2RS1 suffix is the classic contact NBR seal on each side without add-on flingers — grease retention for life inside the sphered-OD ISO 15 envelope. Envelope 45x100x25 mm (1.772x3.937x0.984 in), outer ring 25 mm wide, C 52.7 kN, C0 31.5 kN, Pu 1.34 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,500 r/min; mass 800 g. Envelope arithmetic: the radial section from 45 mm bore to 100 mm OD is 27.5 mm; dividing C 52.7 kN by that section gives 1.916 kN per section millimetre, and the 25 mm overall width is 0.909x the section. Speed ceiling of 4,500 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Bore-to-OD planning: OD 100 over bore 45 is a 2.222x step, while bore/overall-width gives 1.8; the spherical seat in the matching Y-housing must be specified to the 100 mm OD, not to a cylindrical housing bore. Pitch-diameter arithmetic: dm = (45+100)/2 = 72.5 mm; at the 4,500 r/min limiting speed the ball set runs at dn approx 3.26x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. At the printed limiting speed of 4,500 r/min the mean diameter dm = 72.5 mm implies dn about 3.26x10^5 mm.r/min — the speed-demand figure used when comparing this insert with open deep-groove sizes of the same bore. Standard-inner-ring note: unlike YAR/YEL/YSP inserts this 172 execution has NO shaft locking device and NO extended ring — it locates by fits like a normal sealed deep-groove ball bearing, while the sphered outside surface still provides static self-alignment inside the Y-housing. Fit note for 1726309-2RS1: because no locking device exists, shaft and housing fits do the locating work; treat the fit recommendations for sealed deep-groove bearings, and let the spherical OD pivot in the housing rather than forcing axial alignment.", "applications": [ "general machinery using Y-flange and Y-pillow housings", "Y-housing units on standard machined shafts", "fan and conveyor positions ordered as ISO-envelope spares" ], "failure_modes": [ "treated as a normal cylindrical-OD bearing and pressed into a plain bore: the sphered outer surface cannot locate radially without the matching spherical housing seat", "VP274/B lubrication holes blocked by a misaligned housing groove starve the spherical seat during re-greasing", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "misalignment beyond the static seat capability loads the seals continuously, wearing one lip through in weeks", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "The 45x100 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "No locking device means shaft preparation is everything for 1726309-2RS1: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "Catalogue ratings belong to 1726309-2RS1 as the standard std rs1 execution; other order numbers of the 1726309 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726309-2RS1?", "a": "Boundary dimensions: bore 45 mm, sphered OD 100 mm, overall width 25 mm; weight 800 g. Loads: dynamic 52.7 kN, static 31.5 kN, fatigue 1.34 kN; the only published speed is the 4,500 r/min limiting value." }, { "q": "What does the designation 1726309-2RS1 mean?", "a": "reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 09 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 45 mm (code 09 x 5) bore. the -2RS1 suffix is the classic contact NBR seal on each side without add-on flingers — grease retention for life inside the sphered-OD ISO 15 envelope." }, { "q": "Is 1726309-2RS1 the same as a 6309 sealed deep-groove bearing?", "a": "The 45x100x25 mm envelope and ratings follow the 63-series plan, but the OUTER surface is spherically ground for a Y-housing; pressing it into a normal cylindrical bore defeats its design. Treat it as an insert, not a drop-in 63-bearing." }, { "q": "What is a 172-series insert bearing?", "a": "It is an insert bearing with a STANDARD-width inner ring (172 prefix) instead of the extended YAR/YEL/YSP rings; the next digits give the sphered-OD ISO 15 dimension series — 62 for series 02 and 63 for series 03. It locks by fits, like a normal sealed deep-groove bearing, not by screws or a collar." } ], "cross_ref": [ { "equiv_sku": "1726309-B-2RS1-VP274", "equiv_brand": "SKF", "level": "full", "note": "Same 45x100x25 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; 1726309B-2RS1/VP274 is the standard inner ring, fit-located execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "6309", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6309 shares the 45x100x25 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6309 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726309-2RS1" ], "locale_variants": {} }, { "sku": "1726309-B-2RS1-VP274", "brand": "SKF", "manufacturer_designation": "1726309B-2RS1/VP274", "series": "17263-series", "type": "insert", "d_mm": 45, "D_mm": 100, "B_mm": 25, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 31.5, "fatigue_load_limit_kN": 1.34, "limiting_speed_rpm": 4500, "max_rpm": 4500, "weight_g": 810, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The 17263 series order number 1726309B-2RS1/VP274 is a SKF insert bearing (Y-bearing) for a 45 mm shaft: insert bearing with a standard (non-extended) inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 100 mm. The unit is a capped deep-groove ball bearing to the ISO 15 03 envelope whose outer surface is sphered instead of cylindrical, so it combines a standard fit with Y-housing alignment. reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 09 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 45 mm (code 09 x 5) bore. the B-2RS1/VP274 designation combines outer-ring lubrication holes (B) with nitrile contact seals each side (VP274) — the sealed, re-lubricatable execution of the 172 range. Envelope 45x100x25 mm (1.772x3.937x0.984 in), outer ring 25 mm wide, C 52.7 kN, C0 31.5 kN, Pu 1.34 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,500 r/min; mass 810 g. Selection figures for 1726309B-2RS1/VP274: C0/C is 0.598, Pu 1.34 kN is 2.543 % of the 52.7 kN dynamic rating, and the 810 g catalogue mass works out to roughly 18 g per millimetre of the 45 mm bore. Capacity density: 52.7 kN from 0.810 kg of bearing steel is about 65.062 kN per kilogram, and per width millimetre the 25 mm unit carries 2.108 kN of dynamic capacity. Grease-life arithmetic is dominated by speed: at dn approx 3.26x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Static-first planning: the 1.26 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 45 mm shaft, not the 52.7 kN L10 value. Speed ceiling of 4,500 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Lubrication-hole note: the B execution carries outer-ring lubrication holes feeding the sphered outside surface; align the hole with the housing groove before clamping the cap, because a hole sealed off by a misaligned housing traps old grease and starves the spherical seat during re-lubrication. Geometry note: with the standard inner ring the 25 mm width and 45x100 mm bore/OD match the 63-series deep-groove ball envelope, while only the sphered outer surface identifies it as a Y-insert.", "applications": [ "general machinery using Y-flange and Y-pillow housings", "Y-housing units on standard machined shafts", "fan and conveyor positions ordered as ISO-envelope spares" ], "failure_modes": [ "shaft fit wrong (no locking device exists): too loose creeps, too tight removes the residual clearance the spherical seat relies on", "VP274/B lubrication holes blocked by a misaligned housing groove starve the spherical seat during re-greasing", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "No locking device means shaft preparation is everything for 1726309-B-2RS1-VP274: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "The 45x100 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "The 52.7/31.5 kN figures belong specifically to 1726309B-2RS1/VP274; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726309-B-2RS1-VP274?", "a": "Boundary dimensions: bore 45 mm, sphered OD 100 mm, overall width 25 mm; weight 810 g. Loads: dynamic 52.7 kN, static 31.5 kN, fatigue 1.34 kN; the only published speed is the 4,500 r/min limiting value." }, { "q": "What does the designation 1726309B-2RS1/VP274 mean?", "a": "reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 09 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 45 mm (code 09 x 5) bore. the B-2RS1/VP274 designation combines outer-ring lubrication holes (B) with nitrile contact seals each side (VP274) — the sealed, re-lubricatable execution of the 172 range." }, { "q": "Is 1726309-B-2RS1-VP274 the same as a 6309 sealed deep-groove bearing?", "a": "The 45x100x25 mm envelope and ratings follow the 63-series plan, but the OUTER surface is spherically ground for a Y-housing; pressing it into a normal cylindrical bore defeats its design. Treat it as an insert, not a drop-in 63-bearing." }, { "q": "What is a 172-series insert bearing?", "a": "It is an insert bearing with a STANDARD-width inner ring (172 prefix) instead of the extended YAR/YEL/YSP rings; the next digits give the sphered-OD ISO 15 dimension series — 62 for series 02 and 63 for series 03. It locks by fits, like a normal sealed deep-groove bearing, not by screws or a collar." } ], "cross_ref": [ { "equiv_sku": "1726309-2RS1", "equiv_brand": "SKF", "level": "full", "note": "Same 45x100x25 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; 1726309-2RS1 is the standard inner ring, fit-located execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "6309", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6309 shares the 45x100x25 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6309 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726309-B-2RS1-VP274", "1726309B-2RS1/VP274" ], "locale_variants": {} }, { "sku": "1726210-2RS1", "brand": "SKF", "manufacturer_designation": "1726210-2RS1", "series": "17262-series", "type": "insert", "d_mm": 50, "D_mm": 90, "B_mm": 20, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 35.1, "static_load_kN": 23.2, "fatigue_load_limit_kN": 0.98, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The 17262 series order number 1726210-2RS1 is a SKF insert bearing (Y-bearing) for a 50 mm shaft: insert bearing with a standard (non-extended) inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 90 mm. The unit is a capped deep-groove ball bearing to the ISO 15 03 envelope whose outer surface is sphered instead of cylindrical, so it combines a standard fit with Y-housing alignment. reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 10 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 50 mm (code 10 x 5) bore. the -2RS1 suffix is the classic contact NBR seal on each side without add-on flingers — grease retention for life inside the sphered-OD ISO 15 envelope. Envelope 50x90x20 mm (1.969x3.543x0.787 in), outer ring 20 mm wide, C 35.1 kN, C0 23.2 kN, Pu 0.98 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,800 r/min; mass 440 g. Grease-life arithmetic is dominated by speed: at dn approx 3.36x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Mass-to-load ratio for 1726210-2RS1: 12.536 g of catalogue mass per rated kN of C, and 8.8 g per millimetre of bore — useful when comparing executions of the same 50x90 mm envelope on the drawing. Load balance for documentation: C0 23.2 kN against C 35.1 kN gives a 0.661 ratio; mounted-unit positions with shock and standstill loading are normally checked on C0, while conveyor and fan duty are evaluated on the L10 figure. Imperial procurement cross-check: 1.969 in bore, 3.543 in OD, 0.787 in overall width; the 440 g mass converts to 0.440 kg (15.5 oz) for the bill of materials. Pitch-diameter arithmetic: dm = (50+90)/2 = 70 mm; at the 4,800 r/min limiting speed the ball set runs at dn approx 3.36x10^5, reduced from an open bearing mainly by seal lip friction and the life-long grease fill. Standard-inner-ring note: unlike YAR/YEL/YSP inserts this 172 execution has NO shaft locking device and NO extended ring — it locates by fits like a normal sealed deep-groove ball bearing, while the sphered outside surface still provides static self-alignment inside the Y-housing. Fit note for 1726210-2RS1: because no locking device exists, shaft and housing fits do the locating work; treat the fit recommendations for sealed deep-groove bearings, and let the spherical OD pivot in the housing rather than forcing axial alignment.", "applications": [ "Y-housing units on standard machined shafts", "general machinery using Y-flange and Y-pillow housings", "fan and conveyor positions ordered as ISO-envelope spares" ], "failure_modes": [ "VP274/B lubrication holes blocked by a misaligned housing groove starve the spherical seat during re-greasing", "treated as a normal cylindrical-OD bearing and pressed into a plain bore: the sphered outer surface cannot locate radially without the matching spherical housing seat", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "The 50x90 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "No locking device means shaft preparation is everything for 1726210-2RS1: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "Ordering discipline for the 50 mm size: the chapter lists several executions side by side (17262 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726210-2RS1?", "a": "Boundary dimensions: bore 50 mm, sphered OD 90 mm, overall width 20 mm; weight 440 g. Loads: dynamic 35.1 kN, static 23.2 kN, fatigue 0.98 kN; the only published speed is the 4,800 r/min limiting value." }, { "q": "What does the designation 1726210-2RS1 mean?", "a": "reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 10 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 50 mm (code 10 x 5) bore. the -2RS1 suffix is the classic contact NBR seal on each side without add-on flingers — grease retention for life inside the sphered-OD ISO 15 envelope." }, { "q": "What is a 172-series insert bearing?", "a": "It is an insert bearing with a STANDARD-width inner ring (172 prefix) instead of the extended YAR/YEL/YSP rings; the next digits give the sphered-OD ISO 15 dimension series — 62 for series 02 and 63 for series 03. It locks by fits, like a normal sealed deep-groove bearing, not by screws or a collar." }, { "q": "How is axial position secured with no locking device?", "a": "Through the recommended shaft and housing fits, abutments and any snap rings per the catalogue — there are no screws, collar or sleeve. The spherical OD still supplies the static self-alignment in the Y-housing." } ], "cross_ref": [ { "equiv_sku": "6210", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6210 shares the 50x90x20 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6210 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726210-2RS1" ], "locale_variants": {} }, { "sku": "1726310-B-2RS1-VP274", "brand": "SKF", "manufacturer_designation": "1726310B-2RS1/VP274", "series": "17263-series", "type": "insert", "d_mm": 50, "D_mm": 110, "B_mm": 27, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 61.8, "static_load_kN": 38, "fatigue_load_limit_kN": 1.6, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 1000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The 17263 series order number 1726310B-2RS1/VP274 is a SKF insert bearing (Y-bearing) for a 50 mm shaft: insert bearing with a standard (non-extended) inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 110 mm. The unit is a capped deep-groove ball bearing to the ISO 15 03 envelope whose outer surface is sphered instead of cylindrical, so it combines a standard fit with Y-housing alignment. reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 10 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 50 mm (code 10 x 5) bore. the B-2RS1/VP274 designation combines outer-ring lubrication holes (B) with nitrile contact seals each side (VP274) — the sealed, re-lubricatable execution of the 172 range. Envelope 50x110x27 mm (1.969x4.331x1.063 in), outer ring 27 mm wide, C 61.8 kN, C0 38 kN, Pu 1.6 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 1000 g. Mass-to-load ratio for 1726310-B-2RS1-VP274: 16.181 g of catalogue mass per rated kN of C, and 20 g per millimetre of bore — useful when comparing executions of the same 50x110 mm envelope on the drawing. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 68.7 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Static-first planning: the 1.407 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 50 mm shaft, not the 61.8 kN L10 value. Bore-to-OD planning: OD 110 over bore 50 is a 2.2x step, while bore/overall-width gives 1.852; the spherical seat in the matching Y-housing must be specified to the 110 mm OD, not to a cylindrical housing bore. Capacity density: 61.8 kN from 1.000 kg of bearing steel is about 61.8 kN per kilogram, and per width millimetre the 27 mm unit carries 2.289 kN of dynamic capacity. Lubrication-hole note: the B execution carries outer-ring lubrication holes feeding the sphered outside surface; align the hole with the housing groove before clamping the cap, because a hole sealed off by a misaligned housing traps old grease and starves the spherical seat during re-lubrication. Fit note for 1726310-B-2RS1-VP274: because no locking device exists, shaft and housing fits do the locating work; treat the fit recommendations for sealed deep-groove bearings, and let the spherical OD pivot in the housing rather than forcing axial alignment.", "applications": [ "fan and conveyor positions ordered as ISO-envelope spares", "Y-housing units on standard machined shafts", "general machinery using Y-flange and Y-pillow housings" ], "failure_modes": [ "shaft fit wrong (no locking device exists): too loose creeps, too tight removes the residual clearance the spherical seat relies on", "VP274/B lubrication holes blocked by a misaligned housing groove starve the spherical seat during re-greasing", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion" ], "pitfalls": [ "No locking device means shaft preparation is everything for 1726310-B-2RS1-VP274: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "The 50x110 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "The 61.8/38 kN figures belong specifically to 1726310B-2RS1/VP274; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726310-B-2RS1-VP274?", "a": "Boundary dimensions: bore 50 mm, sphered OD 110 mm, overall width 27 mm; weight 1000 g. Loads: dynamic 61.8 kN, static 38 kN, fatigue 1.6 kN; the only published speed is the 4,300 r/min limiting value." }, { "q": "What does the designation 1726310B-2RS1/VP274 mean?", "a": "reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 10 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 50 mm (code 10 x 5) bore. the B-2RS1/VP274 designation combines outer-ring lubrication holes (B) with nitrile contact seals each side (VP274) — the sealed, re-lubricatable execution of the 172 range." }, { "q": "How is axial position secured with no locking device?", "a": "Through the recommended shaft and housing fits, abutments and any snap rings per the catalogue — there are no screws, collar or sleeve. The spherical OD still supplies the static self-alignment in the Y-housing." }, { "q": "What do B and VP274 mean?", "a": "B denotes lubrication holes in the outer ring (only on standard-inner-ring executions); VP274 is the NBR contact-seal package on both sides. The B-2RS1/VP274 article is therefore sealed yet re-lubricatable through the housing." } ], "cross_ref": [ { "equiv_sku": "1726310-2RS1", "equiv_brand": "SKF", "level": "full", "note": "Same 50x110x27 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; 1726310-2RS1 is the standard inner ring, fit-located execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "6310", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6310 shares the 50x110x27 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6310 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726310-B-2RS1-VP274", "1726310B-2RS1/VP274" ], "locale_variants": {} }, { "sku": "1726310-2RS1", "brand": "SKF", "manufacturer_designation": "1726310-2RS1", "series": "17263-series", "type": "insert", "d_mm": 50, "D_mm": 110, "B_mm": 27, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 61.8, "static_load_kN": 38, "fatigue_load_limit_kN": 1.6, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 1050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The 17263 series order number 1726310-2RS1 is a SKF insert bearing (Y-bearing) for a 50 mm shaft: insert bearing with a standard (non-extended) inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 110 mm. The unit is a capped deep-groove ball bearing to the ISO 15 03 envelope whose outer surface is sphered instead of cylindrical, so it combines a standard fit with Y-housing alignment. reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 10 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 50 mm (code 10 x 5) bore. the -2RS1 suffix is the classic contact NBR seal on each side without add-on flingers — grease retention for life inside the sphered-OD ISO 15 envelope. Envelope 50x110x27 mm (1.969x4.331x1.063 in), outer ring 27 mm wide, C 61.8 kN, C0 38 kN, Pu 1.6 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 1050 g. Grease-life arithmetic is dominated by speed: at dn approx 3.44x10^5 the sealed-for-life fill is planned for the catalogue's grease-life regime, which is why the limiting speed and the relubrication interval move together, and high-temperature mounts shorten both even when load is light. Inner-geometry cross-reference: the catalogue shoulder diameters (d1 68.7 mm) set the shaft-abutment and sleeve limits; an abutment larger than these numbers contacts the seal or the inner flinger. Spherical-seat note in numbers: the 110 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 80 = 251.327 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Bore-to-OD planning: OD 110 over bore 50 is a 2.2x step, while bore/overall-width gives 1.852; the spherical seat in the matching Y-housing must be specified to the 110 mm OD, not to a cylindrical housing bore. Speed ceiling of 4,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Standard-inner-ring note: unlike YAR/YEL/YSP inserts this 172 execution has NO shaft locking device and NO extended ring — it locates by fits like a normal sealed deep-groove ball bearing, while the sphered outside surface still provides static self-alignment inside the Y-housing. Geometry note: with the standard inner ring the 27 mm width and 50x110 mm bore/OD match the 63-series deep-groove ball envelope, while only the sphered outer surface identifies it as a Y-insert.", "applications": [ "fan and conveyor positions ordered as ISO-envelope spares", "Y-housing units on standard machined shafts", "general machinery using Y-flange and Y-pillow housings" ], "failure_modes": [ "shaft fit wrong (no locking device exists): too loose creeps, too tight removes the residual clearance the spherical seat relies on", "VP274/B lubrication holes blocked by a misaligned housing groove starve the spherical seat during re-greasing", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "relubricated with incompatible grease that hardens the factory fill and drags the seals", "pressure-greasing through the housing fitting at excessive pressure balloons the NBR seals out of their grooves" ], "pitfalls": [ "No locking device means shaft preparation is everything for 1726310-2RS1: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "The 50x110 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "The 61.8/38 kN figures belong specifically to 1726310-2RS1; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726310-2RS1?", "a": "Boundary dimensions: bore 50 mm, sphered OD 110 mm, overall width 27 mm; weight 1050 g. Loads: dynamic 61.8 kN, static 38 kN, fatigue 1.6 kN; the only published speed is the 4,300 r/min limiting value." }, { "q": "What does the designation 1726310-2RS1 mean?", "a": "reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 10 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 50 mm (code 10 x 5) bore. the -2RS1 suffix is the classic contact NBR seal on each side without add-on flingers — grease retention for life inside the sphered-OD ISO 15 envelope." }, { "q": "How is axial position secured with no locking device?", "a": "Through the recommended shaft and housing fits, abutments and any snap rings per the catalogue — there are no screws, collar or sleeve. The spherical OD still supplies the static self-alignment in the Y-housing." }, { "q": "What do B and VP274 mean?", "a": "B denotes lubrication holes in the outer ring (only on standard-inner-ring executions); VP274 is the NBR contact-seal package on both sides. The B-2RS1/VP274 article is therefore sealed yet re-lubricatable through the housing." } ], "cross_ref": [ { "equiv_sku": "1726310-B-2RS1-VP274", "equiv_brand": "SKF", "level": "full", "note": "Same 50x110x27 mm ISO 15 insert-bearing envelope with catalogue ratings within 10 %; 1726310B-2RS1/VP274 is the standard inner ring, fit-located execution of this size — boundary dimensions interchangeable, locking/seal execution differs." }, { "equiv_sku": "6310", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6310 shares the 50x110x27 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6310 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726310-2RS1" ], "locale_variants": {} }, { "sku": "1726211-2RS1", "brand": "SKF", "manufacturer_designation": "1726211-2RS1", "series": "17262-series", "type": "insert", "d_mm": 55, "D_mm": 100, "B_mm": 21, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.6, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The 17262 series order number 1726211-2RS1 is a SKF insert bearing (Y-bearing) for a 55 mm shaft: insert bearing with a standard (non-extended) inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 100 mm. The unit is a capped deep-groove ball bearing to the ISO 15 03 envelope whose outer surface is sphered instead of cylindrical, so it combines a standard fit with Y-housing alignment. reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 11 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 55 mm (code 11 x 5) bore. the -2RS1 suffix is the classic contact NBR seal on each side without add-on flingers — grease retention for life inside the sphered-OD ISO 15 envelope. Envelope 55x100x21 mm (2.165x3.937x0.827 in), outer ring 21 mm wide, C 43.6 kN, C0 29 kN, Pu 1.25 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,300 r/min; mass 600 g. Mass-to-load ratio for 1726211-2RS1: 13.761 g of catalogue mass per rated kN of C, and 10.909 g per millimetre of bore — useful when comparing executions of the same 55x100 mm envelope on the drawing. Rating split for the maintenance file: dynamic 43.6 kN (L10), static 29 kN (s0 shock check), fatigue 1.25 kN (adjusted life) — three separate uses for 1726211-2RS1, none interchangeable with another. Mounting verification on 1726211-2RS1 uses the printed catalogue procedure rather than torque guessing. Envelope arithmetic: the radial section from 55 mm bore to 100 mm OD is 22.5 mm; dividing C 43.6 kN by that section gives 1.938 kN per section millimetre, and the 21 mm overall width is 0.933x the section. Speed ceiling of 4,300 r/min is the catalogue mechanical limit for THIS execution; seal lip and flinger drag, not steel fatigue, are normally what cap it, so real fan duty is planned well below it. Standard-inner-ring note: unlike YAR/YEL/YSP inserts this 172 execution has NO shaft locking device and NO extended ring — it locates by fits like a normal sealed deep-groove ball bearing, while the sphered outside surface still provides static self-alignment inside the Y-housing. Fit note for 1726211-2RS1: because no locking device exists, shaft and housing fits do the locating work; treat the fit recommendations for sealed deep-groove bearings, and let the spherical OD pivot in the housing rather than forcing axial alignment.", "applications": [ "Y-housing units on standard machined shafts", "fan and conveyor positions ordered as ISO-envelope spares", "general machinery using Y-flange and Y-pillow housings" ], "failure_modes": [ "shaft fit wrong (no locking device exists): too loose creeps, too tight removes the residual clearance the spherical seat relies on", "VP274/B lubrication holes blocked by a misaligned housing groove starve the spherical seat during re-greasing", "water or slurry past the seal lip emulsifies the life-long grease and rusts the flinger recess", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches" ], "pitfalls": [ "No locking device means shaft preparation is everything for 1726211-2RS1: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "The 55x100 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "The 43.6/29 kN figures belong specifically to 1726211-2RS1; HV stainless, AG agricultural and VE495 zinc-plated variants of the same envelope publish derated values, so write the complete order number including suffixes on the purchase and maintenance records." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726211-2RS1?", "a": "Boundary dimensions: bore 55 mm, sphered OD 100 mm, overall width 21 mm; weight 600 g. Loads: dynamic 43.6 kN, static 29 kN, fatigue 1.25 kN; the only published speed is the 4,300 r/min limiting value." }, { "q": "What does the designation 1726211-2RS1 mean?", "a": "reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 11 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 55 mm (code 11 x 5) bore. the -2RS1 suffix is the classic contact NBR seal on each side without add-on flingers — grease retention for life inside the sphered-OD ISO 15 envelope." }, { "q": "How is axial position secured with no locking device?", "a": "Through the recommended shaft and housing fits, abutments and any snap rings per the catalogue — there are no screws, collar or sleeve. The spherical OD still supplies the static self-alignment in the Y-housing." }, { "q": "What do B and VP274 mean?", "a": "B denotes lubrication holes in the outer ring (only on standard-inner-ring executions); VP274 is the NBR contact-seal package on both sides. The B-2RS1/VP274 article is therefore sealed yet re-lubricatable through the housing." } ], "cross_ref": [ { "equiv_sku": "6211", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6211 shares the 55x100x21 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6211 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726211-2RS1" ], "locale_variants": {} }, { "sku": "1726212-2RS1", "brand": "SKF", "manufacturer_designation": "1726212-2RS1", "series": "17262-series", "type": "insert", "d_mm": 60, "D_mm": 110, "B_mm": 22, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.7, "static_load_kN": 36, "fatigue_load_limit_kN": 1.53, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 770, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The 17262 series order number 1726212-2RS1 is a SKF insert bearing (Y-bearing) for a 60 mm shaft: insert bearing with a standard (non-extended) inner ring, built to the ISO 15 diameter-series envelope with a sphered OD of 110 mm. The unit is a capped deep-groove ball bearing to the ISO 15 03 envelope whose outer surface is sphered instead of cylindrical, so it combines a standard fit with Y-housing alignment. reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 12 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 60 mm (code 12 x 5) bore. the -2RS1 suffix is the classic contact NBR seal on each side without add-on flingers — grease retention for life inside the sphered-OD ISO 15 envelope. Envelope 60x110x22 mm (2.362x4.331x0.866 in), outer ring 22 mm wide, C 52.7 kN, C0 36 kN, Pu 1.53 kN. The catalogue publishes a single speed ceiling, the limiting speed: 4,000 r/min; mass 770 g. Capacity density: 52.7 kN from 0.770 kg of bearing steel is about 68.442 kN per kilogram, and per width millimetre the 22 mm unit carries 2.395 kN of dynamic capacity. Static-first planning: the 1.636 kN of C0 per overall-width millimetre is the figure for belt tension peaks and rotor imbalance standstill loads on the 60 mm shaft, not the 52.7 kN L10 value. Mounting verification on 1726212-2RS1 uses the printed catalogue procedure rather than torque guessing. Spherical-seat note in numbers: the 110 mm OD is ground spherical, so the self-aligning pivot happens on a circle roughly pi x 85 = 267.035 mm in mean circumference — keep that interface greased, because corrosion locking turns the pivot into a fixed misaligned mount. Fatigue-limit check: Pu 1.53 kN is the equivalent-load threshold under which the SKF adjusted-rating model credits very long life for 1726212-2RS1 — most belt-driven mounted-unit loads sit comfortably under 2.903 % of C. Standard-inner-ring note: unlike YAR/YEL/YSP inserts this 172 execution has NO shaft locking device and NO extended ring — it locates by fits like a normal sealed deep-groove ball bearing, while the sphered outside surface still provides static self-alignment inside the Y-housing. Fit note for 1726212-2RS1: because no locking device exists, shaft and housing fits do the locating work; treat the fit recommendations for sealed deep-groove bearings, and let the spherical OD pivot in the housing rather than forcing axial alignment.", "applications": [ "process positions where the spherical seat and a normal fit are both required", "heavy Y-housed conveyor and fan shafts" ], "failure_modes": [ "VP274/B lubrication holes blocked by a misaligned housing groove starve the spherical seat during re-greasing", "treated as a normal cylindrical-OD bearing and pressed into a plain bore: the sphered outer surface cannot locate radially without the matching spherical housing seat", "two bearings of the same size but different locking styles swapped during overhaul — shaft preparation (dimples, collar space, sleeve seat) no longer matches", "sphered OD and spherical housing bore left dry or painted over: the static self-aligning feature freezes solid with corrosion", "relubricated with incompatible grease that hardens the factory fill and drags the seals" ], "pitfalls": [ "When ordering a like-for-like replacement, note whether the old part carried the B lubrication-hole execution: housing grooves aligned to B holes leave the non-B seal-only variant without its re-greasing path.", "No locking device means shaft preparation is everything for 1726212-2RS1: observe the fit, abutment and circlip recommendations rather than expecting screws or a collar to rescue a loose shaft.", "The 60x110 mm envelope matching a 63-series bearing tempts substitution into a cylindrical housing — do not: the sphered OD only works in the mating spherical Y-housing bore.", "Ordering discipline for the 60 mm size: the chapter lists several executions side by side (17262 locking style x seal package x application variant); a bare-number substitution needs a fresh dimension, speed and rating check rather than a like-for-like assumption." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1726212-2RS1?", "a": "Boundary dimensions: bore 60 mm, sphered OD 110 mm, overall width 22 mm; weight 770 g. Loads: dynamic 52.7 kN, static 36 kN, fatigue 1.53 kN; the only published speed is the 4,000 r/min limiting value." }, { "q": "What does the designation 1726212-2RS1 mean?", "a": "reading 1726xx: 172 = insert bearing with a standard-width inner ring, 6 = ISO 15 dimension series 03 with a spherically shaped outside surface for self-aligning in a Y-housing. the final two digits 12 follow the standard bore-code rule (03 = 17 mm, then x5), giving a 60 mm (code 12 x 5) bore. the -2RS1 suffix is the classic contact NBR seal on each side without add-on flingers — grease retention for life inside the sphered-OD ISO 15 envelope." }, { "q": "What do B and VP274 mean?", "a": "B denotes lubrication holes in the outer ring (only on standard-inner-ring executions); VP274 is the NBR contact-seal package on both sides. The B-2RS1/VP274 article is therefore sealed yet re-lubricatable through the housing." }, { "q": "Is 1726212-2RS1 the same as a 6312 sealed deep-groove bearing?", "a": "The 60x110x22 mm envelope and ratings follow the 63-series plan, but the OUTER surface is spherically ground for a Y-housing; pressing it into a normal cylindrical bore defeats its design. Treat it as an insert, not a drop-in 63-bearing." } ], "cross_ref": [ { "equiv_sku": "6212", "equiv_brand": "SKF", "level": "full", "note": "SKF SKF 6212 shares the 60x110x22 mm ISO 15 dimension-series 03 envelope and ratings within 10 %, but this SKF insert has a SPHERED outside surface for a Y-housing while 6212 has a cylindrical OD for a machined bore — envelope/load match, never a drop-in substitute." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018)", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1726212-2RS1" ], "locale_variants": {} }, { "sku": "32004-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32004 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 20, "D_mm": 42, "B_mm": 15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 29.7, "static_load_kN": 27, "fatigue_load_limit_kN": 2.65, "max_rpm": 16000, "reference_speed_rpm": 13000, "limiting_speed_rpm": 16000, "weight_g": 99, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32004 X belongs to the SKF single-row tapered roller range — the 20 mm bore entry in the 32000 series, dimensioned 42 mm OD and 15 mm wide to the ISO 355 boundary plan.On the SKF nameplate, 32004 follows the ISO 355 convention: 3 for the tapered-roller type, 20 for the low-friction section, final digits 04 for the 20 mm bore. In SKF suffix language a bare 32004 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Speed planning uses two different ceilings: 13,000 r/min thermal reference and 16,000 r/min mechanical limiting speed. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 32004 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Load system: the 29.7 kN basic dynamic rating C and 27 kN static rating C0 give a C0/C balance of 0.91, and dividing C by the 20 mm bore yields 1.48 kN per millimetre of journal — a density metric that compares across families; the 2.65 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 20 mm shaft carrying variable duty.", "applications": [ "light-duty gearbox input/output shafts", "electric-motor pinion shafts", "steering knuckles and small differentials", "agricultural implement hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "At a 20 mm bore the thin cone and cup are easily distorted by an over-tight shaft nut; check seat runout (target Ra ≤ 0.8 µm) and torque the locknut progressively — a pinched 32004 shows up as gearbox vibration long before it fails.", "The 320 series at 20 mm bore (42×15 mm) is the low-friction, higher-speed section; it carries less thrust than a 30204 of the same bore, so verify the axial load share before swapping.", "Do not mix brands or executions inside one 32004 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32004 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Shaft and housing fillets must clear the bearing chamfer so the 15 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 29.7/27 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32004 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32004 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32004?", "a": "The SKF 32004 X is a single-row tapered roller bearing with 20 mm bore, 42 mm outer diameter and 15 mm width (0.787 × 1.654 × 0.591 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 29.7 kN, C0 27 kN, fatigue load limit Pu 2.65 kN, reference speed 13,000 r/min, limiting speed 16,000 r/min, mass about 99 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32004 bore code work?", "a": "The last two digits of 32004 are bore code 04, so 04 × 5 = 20 mm bore. The 42 mm OD and 15 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32004 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32004 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32004 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32004 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32004", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32004", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32004" ], "locale_variants": {} }, { "sku": "32005-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32005 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 25, "D_mm": 47, "B_mm": 15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.2, "static_load_kN": 32.5, "fatigue_load_limit_kN": 3.25, "max_rpm": 14000, "reference_speed_rpm": 12000, "limiting_speed_rpm": 14000, "weight_g": 110, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 25 mm shaft carrying combined load, SKF lists 32005 under catalogue execution SKF 32005 X: one open single-row tapered roller bearing in the low-friction section of the 32000 family.The code breaks down as type prefix 3 (tapered roller), series 20 (the low-friction section), and bore code 05 = 25 mm; dimensions 25×47×15 mm therefore match the ISO 355 envelope. In SKF suffix language a bare 32005 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. With C 33.2 kN and C0 32.5 kN, the 32005 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 14,000 r/min. Because the contact line is tapered, one 32005 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 25 mm shaft typically takes a k5 seat with an H7 housing bore. Material and manufacturing detail: the 110 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 32000 ISO envelope, with the pressed-steel cage contributing roughly 3 g of the total; the 25 mm bore is ground to IT5 roundness and the 47 mm OD to IT5 cylindricity, and the 15 mm width tolerance keeps the pair-setting scatter within the ISO preload class.", "applications": [ "steering knuckles and small differentials", "agricultural implement hubs", "small conveyor drive pulleys", "power-tool gear heads" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At a 25 mm bore the thin cone and cup are easily distorted by an over-tight shaft nut; check seat runout (target Ra ≤ 0.8 µm) and torque the locknut progressively — a pinched 32005 shows up as gearbox vibration long before it fails.", "The 320 series at 25 mm bore (47×15 mm) is the low-friction, higher-speed section; it carries less thrust than a 30205 of the same bore, so verify the axial load share before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32005 mounting error.", "Setting is a design value, not an assembly feel: excessive preload in the 32005 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Catalogue reference speed and limiting speed are different limits: the 12,000 r/min reference is a thermal criterion under load, while the 14,000 r/min limiting value is the mechanical ceiling — observe both.", "The 33.2/32.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32005 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32005 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32005?", "a": "The SKF 32005 X is a single-row tapered roller bearing with 25 mm bore, 47 mm outer diameter and 15 mm width (0.984 × 1.85 × 0.591 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 33.2 kN, C0 32.5 kN, fatigue load limit Pu 3.25 kN, reference speed 12,000 r/min, limiting speed 14,000 r/min, mass about 110 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32005 bore code work?", "a": "The last two digits of 32005 are bore code 05, so 05 × 5 = 25 mm bore. The 47 mm OD and 15 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32005 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32005 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32005 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32005 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32005", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32005", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32005" ], "locale_variants": {} }, { "sku": "32006-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32006 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 55, "B_mm": 17, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 43.9, "static_load_kN": 44, "fatigue_load_limit_kN": 4.55, "max_rpm": 12000, "reference_speed_rpm": 10000, "limiting_speed_rpm": 12000, "weight_g": 170, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32006 (SKF 32006 X) is the low-friction section tapered roller choice for a 30 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 55×17 mm ISO 355 envelope.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 20 is the ISO 355 diameter/width series (low-friction section), and the last two digits encode the 30 mm bore; the 55 mm OD and 17 mm width follow the ISO 355 general plan. In SKF suffix language a bare 32006 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 4.55 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.00 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. For a 30 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 32006 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Dimensional interchange map: within the 32000 series at 30 mm bore, the 55 mm OD and 17 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 12.5 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 170 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "On this 30 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 32006 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 30 mm bore (55×17 mm) is the low-friction, higher-speed section; it carries less thrust than a 30206 of the same bore, so verify the axial load share before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32006 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "A single 32006 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The 32006 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 43.9/44 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32006 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32006 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32006?", "a": "The SKF 32006 X is a single-row tapered roller bearing with 30 mm bore, 55 mm outer diameter and 17 mm width (1.181 × 2.165 × 0.669 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 43.9 kN, C0 44 kN, fatigue load limit Pu 4.55 kN, reference speed 10,000 r/min, limiting speed 12,000 r/min, mass about 170 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32006 bore code work?", "a": "The last two digits of 32006 are bore code 06, so 06 × 5 = 30 mm bore. The 55 mm OD and 17 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32006 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32006 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32006 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32006 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32006", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32006", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32006" ], "locale_variants": {} }, { "sku": "32007-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32007 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 62, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 52.3, "static_load_kN": 54, "fatigue_load_limit_kN": 5.85, "max_rpm": 10000, "reference_speed_rpm": 8500, "limiting_speed_rpm": 10000, "weight_g": 230, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF 32007 X in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 35 mm shaft, low-friction section, with an open pressed-steel-cage execution and one-direction axial capacity.Digit by digit, 32007 reads as bearing type 3 (single-row tapered roller), low-friction section series 20, and bore reference 07 resolving to 35 mm; 62 mm OD and 18 mm width are the matching ISO 355 boundary values. In SKF suffix language a bare 32007 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 1.03 (static 54 kN against dynamic 52.3 kN), typical of a tapered roller sized for axial capacity, and the 5.85 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Mounting practice for 32007: the rotating cone takes the interference fit (k5 on a 35 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Operating context for the 35 mm bore: a shaft of this diameter in the medium-bore band typically runs between 28000 and 42000 r/min in real machinery, and the 62 mm outside diameter places the housing shoulder at 70 mm outer abutment; the 18 mm width and 230 g mass together set the shaft critical speed and the housing resonance check for this 32000-series envelope.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 35 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 32007 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 35 mm bore (62×18 mm) is the low-friction, higher-speed section; it carries less thrust than a 30207 of the same bore, so verify the axial load share before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 32007 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "At the 52.3 kN rating of 32007, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 10,000 r/min speed end and heavier preload only where moment stiffness dominates.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 62 mm cup race release as noise within the first running hours.", "The 52.3/54 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32007 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32007 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32007?", "a": "The SKF 32007 X is a single-row tapered roller bearing with 35 mm bore, 62 mm outer diameter and 18 mm width (1.378 × 2.441 × 0.709 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 52.3 kN, C0 54 kN, fatigue load limit Pu 5.85 kN, reference speed 8,500 r/min, limiting speed 10,000 r/min, mass about 230 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32007 bore code work?", "a": "The last two digits of 32007 are bore code 07, so 07 × 5 = 35 mm bore. The 62 mm OD and 18 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32007 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32007 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32007 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32007 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32007", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32007", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32007" ], "locale_variants": {} }, { "sku": "32008-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32008 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 68, "B_mm": 19, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 64.7, "static_load_kN": 71, "fatigue_load_limit_kN": 7.65, "max_rpm": 9500, "reference_speed_rpm": 7500, "limiting_speed_rpm": 9500, "weight_g": 280, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32008 is a single-row tapered roller bearing in the ISO 32000 dimension series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Numbering ties the bearing to its envelope: 32008 means tapered-roller type 3, low-friction section series 20, 40 mm bore — which is why the 68×19 mm outline swaps dimensionally with other ISO 355 bearings of the same code. In SKF suffix language a bare 32008 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 14.0 mm radial section height ((68−40)/2) and 280 g catalogue mass frame a 40 mm bore bearing rated at 64.7 kN C — roughly 1.62 kN of dynamic capacity per millimetre of bore before application factors. Fit selection follows the rotating ring — interference on a rotating cone — and two 32008 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Cross-section geometry: the 14.0 mm half-section ((68−40)/2) of this 32000-series unit places the roller large-end pitch diameter at roughly 54 mm, and the 19 mm axial width is split between cone (10 mm) and cup rib (9 mm) — a geometry that sets the contact angle and, with the 280 g rotating cone mass, the critical speed at which cage-roller imbalance begins.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "On this 40 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 32008 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 40 mm bore (68×19 mm) is the low-friction, higher-speed section; it carries less thrust than a 30208 of the same bore, so verify the axial load share before swapping.", "A single 32008 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32008 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 64.7/71 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32008 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32008 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32008?", "a": "The SKF 32008 X is a single-row tapered roller bearing with 40 mm bore, 68 mm outer diameter and 19 mm width (1.575 × 2.677 × 0.748 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 64.7 kN, C0 71 kN, fatigue load limit Pu 7.65 kN, reference speed 7,500 r/min, limiting speed 9,500 r/min, mass about 280 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32008 bore code work?", "a": "The last two digits of 32008 are bore code 08, so 08 × 5 = 40 mm bore. The 68 mm OD and 19 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32008 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32008 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32008 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32008 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32008", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32008", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32008" ], "locale_variants": {} }, { "sku": "32009-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32009 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 75, "B_mm": 20, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 71.7, "static_load_kN": 80, "fatigue_load_limit_kN": 8.8, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500, "weight_g": 340, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 32009 X is a 45×75×20 mm single-row tapered roller bearing — the low-friction section entry in the 32000 series, with an asymmetric raceway cut for thrust capacity and separable mounting.On the SKF nameplate, 32009 follows the ISO 355 convention: 3 for the tapered-roller type, 20 for the low-friction section, final digits 09 for the 45 mm bore. In SKF suffix language a bare 32009 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Catalogue mass 340 g for the 45×75×20 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. A single 32009 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Journal and housing interface: the 45 mm bore takes a k5 shaft seat (upper deviation ~0.090 mm for this diameter range) and the 75 mm outside diameter pairs with an H7 housing bore tolerance band of 75.000/75.020 mm; the 20 mm width defines the shoulder depth, and the 340 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "On this 45 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 32009 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 45 mm bore (75×20 mm) is the low-friction, higher-speed section; it carries less thrust than a 30209 of the same bore, so verify the axial load share before swapping.", "At the 71.7 kN rating of 32009, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 8,500 r/min speed end and heavier preload only where moment stiffness dominates.", "Do not mix brands or executions inside one 32009 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The 340 g mass and 20 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 32009.", "The 71.7/80 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32009 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32009 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32009?", "a": "The SKF 32009 X is a single-row tapered roller bearing with 45 mm bore, 75 mm outer diameter and 20 mm width (1.772 × 2.953 × 0.787 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 71.7 kN, C0 80 kN, fatigue load limit Pu 8.8 kN, reference speed 7,000 r/min, limiting speed 8,500 r/min, mass about 340 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32009 bore code work?", "a": "The last two digits of 32009 are bore code 09, so 09 × 5 = 45 mm bore. The 75 mm OD and 20 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32009 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32009 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32009 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32009 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32009", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32009", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32009" ], "locale_variants": {} }, { "sku": "32010-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32010 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 80, "B_mm": 20, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 75.1, "static_load_kN": 88, "fatigue_load_limit_kN": 9.65, "max_rpm": 8000, "reference_speed_rpm": 6300, "limiting_speed_rpm": 8000, "weight_g": 380, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 32010 appears as SKF 32010 X: an open, single-row tapered roller bearing in the low-friction section of the 32000 dimension series, supplied with a pressed-steel cage as standard.Digit by digit, 32010 reads as bearing type 3 (single-row tapered roller), low-friction section series 20, and bore reference 10 resolving to 50 mm; 80 mm OD and 20 mm width are the matching ISO 355 boundary values. In SKF suffix language a bare 32010 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Speed planning uses two different ceilings: 6,300 r/min thermal reference and 8,000 r/min mechanical limiting speed. For a 50 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 32010 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Material and manufacturing detail: the 380 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 32000 ISO envelope, with the pressed-steel cage contributing roughly 11 g of the total; the 50 mm bore is ground to IT5 roundness and the 80 mm OD to IT5 cylindricity, and the 20 mm width tolerance keeps the pair-setting scatter within the ISO preload class.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 50 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 32010 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 50 mm bore (80×20 mm) is the low-friction, higher-speed section; it carries less thrust than a 30210 of the same bore, so verify the axial load share before swapping.", "At the 75.1 kN rating of 32010, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 8,000 r/min speed end and heavier preload only where moment stiffness dominates.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32010 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Catalogue reference speed and limiting speed are different limits: the 6,300 r/min reference is a thermal criterion under load, while the 8,000 r/min limiting value is the mechanical ceiling — observe both.", "The 75.1/88 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32010 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32010 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32010?", "a": "The SKF 32010 X is a single-row tapered roller bearing with 50 mm bore, 80 mm outer diameter and 20 mm width (1.969 × 3.15 × 0.787 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 75.1 kN, C0 88 kN, fatigue load limit Pu 9.65 kN, reference speed 6,300 r/min, limiting speed 8,000 r/min, mass about 380 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32010 bore code work?", "a": "The last two digits of 32010 are bore code 10, so 10 × 5 = 50 mm bore. The 80 mm OD and 20 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32010 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32010 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32010 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32010 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32010", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32010", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32010" ], "locale_variants": {} }, { "sku": "32011-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32011 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 90, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 99.4, "static_load_kN": 116, "fatigue_load_limit_kN": 12.9, "max_rpm": 7000, "reference_speed_rpm": 5600, "limiting_speed_rpm": 7000, "weight_g": 560, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32011 X belongs to the SKF single-row tapered roller range — the 55 mm bore entry in the 32000 series, dimensioned 90 mm OD and 23 mm wide to the ISO 355 boundary plan.Numbering ties the bearing to its envelope: 32011 means tapered-roller type 3, low-friction section series 20, 55 mm bore — which is why the 90×23 mm outline swaps dimensionally with other ISO 355 bearings of the same code. In SKF suffix language a bare 32011 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. With C 99.4 kN and C0 116 kN, the 32011 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 7,000 r/min. Mounting practice for 32011: the rotating cone takes the interference fit (k5 on a 55 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Dimensional interchange map: within the 32000 series at 55 mm bore, the 90 mm OD and 23 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 17.5 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 560 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "On this 55 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 32011 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 55 mm bore (90×23 mm) is the low-friction, higher-speed section; it carries less thrust than a 30211 of the same bore, so verify the axial load share before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32011 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Do not mix brands or executions inside one 32011 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The 32011 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 99.4/116 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32011 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32011 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32011?", "a": "The SKF 32011 X is a single-row tapered roller bearing with 55 mm bore, 90 mm outer diameter and 23 mm width (2.165 × 3.543 × 0.906 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 99.4 kN, C0 116 kN, fatigue load limit Pu 12.9 kN, reference speed 5,600 r/min, limiting speed 7,000 r/min, mass about 560 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32011 bore code work?", "a": "The last two digits of 32011 are bore code 11, so 11 × 5 = 55 mm bore. The 90 mm OD and 23 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32011 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32011 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32011 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32011 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32011", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32011", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32011" ], "locale_variants": {} }, { "sku": "32013-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32013 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 100, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 103, "static_load_kN": 127, "fatigue_load_limit_kN": 14, "max_rpm": 6000, "reference_speed_rpm": 5000, "limiting_speed_rpm": 6000, "weight_g": 630, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32013 (SKF 32013 X) is the low-friction section tapered roller choice for a 65 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 100×23 mm ISO 355 envelope.The code breaks down as type prefix 3 (tapered roller), series 20 (the low-friction section), and bore code 13 = 65 mm; dimensions 65×100×23 mm therefore match the ISO 355 envelope. In SKF suffix language a bare 32013 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 1.23 (static 127 kN against dynamic 103 kN), typical of a tapered roller sized for axial capacity, and the 14 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. A single 32013 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Cross-section geometry: the 17.5 mm half-section ((100−65)/2) of this 32000-series unit places the roller large-end pitch diameter at roughly 82 mm, and the 23 mm axial width is split between cone (13 mm) and cup rib (10 mm) — a geometry that sets the contact angle and, with the 630 g rotating cone mass, the critical speed at which cage-roller imbalance begins.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Mount the 65 mm bore 32013 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 65 mm bore (100×23 mm) is the low-friction, higher-speed section; it carries less thrust than a 30213 of the same bore, so verify the axial load share before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32013 mounting error.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32013 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 103/127 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32013 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32013 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32013?", "a": "The SKF 32013 X is a single-row tapered roller bearing with 65 mm bore, 100 mm outer diameter and 23 mm width (2.559 × 3.937 × 0.906 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 103 kN, C0 127 kN, fatigue load limit Pu 14 kN, reference speed 5,000 r/min, limiting speed 6,000 r/min, mass about 630 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32013 bore code work?", "a": "The last two digits of 32013 are bore code 13, so 13 × 5 = 65 mm bore. The 100 mm OD and 23 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32013 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32013 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32013 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32013 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32013", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32013", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32013" ], "locale_variants": {} }, { "sku": "32014-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32014 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 110, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 125, "static_load_kN": 153, "fatigue_load_limit_kN": 17.3, "max_rpm": 5600, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5600, "weight_g": 850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF 32014 X in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 70 mm shaft, low-friction section, with an open pressed-steel-cage execution and one-direction axial capacity.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 20 is the ISO 355 diameter/width series (low-friction section), and the last two digits encode the 70 mm bore; the 110 mm OD and 25 mm width follow the ISO 355 general plan. In SKF suffix language a bare 32014 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 20.0 mm radial section height ((110−70)/2) and 850 g catalogue mass frame a 70 mm bore bearing rated at 125 kN C — roughly 1.79 kN of dynamic capacity per millimetre of bore before application factors. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 32014 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Journal and housing interface: the 70 mm bore takes a k5 shaft seat (upper deviation ~0.140 mm for this diameter range) and the 110 mm outside diameter pairs with an H7 housing bore tolerance band of 110.000/110.020 mm; the 25 mm width defines the shoulder depth, and the 850 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "Mount the 70 mm bore 32014 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 70 mm bore (110×25 mm) is the low-friction, higher-speed section; it carries less thrust than a 30214 of the same bore, so verify the axial load share before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32014 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Setting is a design value, not an assembly feel: excessive preload in the 32014 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The 850 g mass and 25 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 32014.", "The 125/153 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32014 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32014 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32014?", "a": "The SKF 32014 X is a single-row tapered roller bearing with 70 mm bore, 110 mm outer diameter and 25 mm width (2.756 × 4.331 × 0.984 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 125 kN, C0 153 kN, fatigue load limit Pu 17.3 kN, reference speed 4,500 r/min, limiting speed 5,600 r/min, mass about 850 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32014 bore code work?", "a": "The last two digits of 32014 are bore code 14, so 14 × 5 = 70 mm bore. The 110 mm OD and 25 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32014 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32014 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32014 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32014 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32014", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32014", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32014" ], "locale_variants": {} }, { "sku": "32015-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32015 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 115, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 130, "static_load_kN": 163, "fatigue_load_limit_kN": 18.6, "max_rpm": 5300, "reference_speed_rpm": 4300, "limiting_speed_rpm": 5300, "weight_g": 910, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32015 is a single-row tapered roller bearing in the ISO 32000 dimension series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Digit by digit, 32015 reads as bearing type 3 (single-row tapered roller), low-friction section series 20, and bore reference 15 resolving to 75 mm; 115 mm OD and 25 mm width are the matching ISO 355 boundary values. In SKF suffix language a bare 32015 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Catalogue mass 910 g for the 75×115×25 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 32015 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Speed envelope and thermal behaviour: at 4,300 r/min thermal reference, the 75 mm bore shaft runs at a dn of 323k, and the 20.0 mm section dissipates heat through the cup-to-housing contact path; the 5,300 r/min mechanical ceiling reflects cage strength, and the 910 g spinning cone contributes gyroscopic moment under rapid speed reversal.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "Mount the 75 mm bore 32015 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 75 mm bore (115×25 mm) is the low-friction, higher-speed section; it carries less thrust than a 30215 of the same bore, so verify the axial load share before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 32015 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "A single 32015 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Open 32015 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 130/163 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32015 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32015 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32015?", "a": "The SKF 32015 X is a single-row tapered roller bearing with 75 mm bore, 115 mm outer diameter and 25 mm width (2.953 × 4.528 × 0.984 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 130 kN, C0 163 kN, fatigue load limit Pu 18.6 kN, reference speed 4,300 r/min, limiting speed 5,300 r/min, mass about 910 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32015 bore code work?", "a": "The last two digits of 32015 are bore code 15, so 15 × 5 = 75 mm bore. The 115 mm OD and 25 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32015 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32015 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32015 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32015 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32015", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32015", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32015" ], "locale_variants": {} }, { "sku": "32016-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32016 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 125, "B_mm": 29, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 168, "static_load_kN": 216, "fatigue_load_limit_kN": 24.5, "max_rpm": 5000, "reference_speed_rpm": 4000, "limiting_speed_rpm": 5000, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 32016 X is a 80×125×29 mm single-row tapered roller bearing — the low-friction section entry in the 32000 series, with an asymmetric raceway cut for thrust capacity and separable mounting.Numbering ties the bearing to its envelope: 32016 means tapered-roller type 3, low-friction section series 20, 80 mm bore — which is why the 125×29 mm outline swaps dimensionally with other ISO 355 bearings of the same code. In SKF suffix language a bare 32016 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 4,000 r/min reference speed the 22.5 mm-section 32016 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 5,000 r/min as the mechanical ceiling. Because the contact line is tapered, one 32016 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 80 mm shaft typically takes a k5 seat with an H7 housing bore. Load system: the 168 kN basic dynamic rating C and 216 kN static rating C0 give a C0/C balance of 1.29, and dividing C by the 80 mm bore yields 2.10 kN per millimetre of journal — a density metric that compares across families; the 24.5 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 80 mm shaft carrying variable duty.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "Mount the 80 mm bore 32016 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 80 mm bore (125×29 mm) is the low-friction, higher-speed section; it carries less thrust than a 30216 of the same bore, so verify the axial load share before swapping.", "A single 32016 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "At the 168 kN rating of 32016, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 5,000 r/min speed end and heavier preload only where moment stiffness dominates.", "Shaft and housing fillets must clear the bearing chamfer so the 29 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 168/216 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32016 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32016 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32016?", "a": "The SKF 32016 X is a single-row tapered roller bearing with 80 mm bore, 125 mm outer diameter and 29 mm width (3.15 × 4.921 × 1.142 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 168 kN, C0 216 kN, fatigue load limit Pu 24.5 kN, reference speed 4,000 r/min, limiting speed 5,000 r/min, mass about 1300 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32016 bore code work?", "a": "The last two digits of 32016 are bore code 16, so 16 × 5 = 80 mm bore. The 125 mm OD and 29 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32016 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32016 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32016 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32016 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32016", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32016", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32016" ], "locale_variants": {} }, { "sku": "32017-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32017 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 130, "B_mm": 29, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 171, "static_load_kN": 224, "fatigue_load_limit_kN": 25.5, "max_rpm": 4800, "reference_speed_rpm": 3800, "limiting_speed_rpm": 4800, "weight_g": 1350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 32017 appears as SKF 32017 X: an open, single-row tapered roller bearing in the low-friction section of the 32000 dimension series, supplied with a pressed-steel cage as standard.On the SKF nameplate, 32017 follows the ISO 355 convention: 3 for the tapered-roller type, 20 for the low-friction section, final digits 17 for the 85 mm bore. In SKF suffix language a bare 32017 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Speed planning uses two different ceilings: 3,800 r/min thermal reference and 4,800 r/min mechanical limiting speed. For a 85 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 32017 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Material and manufacturing detail: the 1350 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 32000 ISO envelope, with the pressed-steel cage contributing roughly 41 g of the total; the 85 mm bore is ground to IT5 roundness and the 130 mm OD to IT5 cylindricity, and the 29 mm width tolerance keeps the pair-setting scatter within the ISO preload class.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Mount the 85 mm bore 32017 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 85 mm bore (130×29 mm) is the low-friction, higher-speed section; it carries less thrust than a 30217 of the same bore, so verify the axial load share before swapping.", "At the 171 kN rating of 32017, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 4,800 r/min speed end and heavier preload only where moment stiffness dominates.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32017 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Catalogue reference speed and limiting speed are different limits: the 3,800 r/min reference is a thermal criterion under load, while the 4,800 r/min limiting value is the mechanical ceiling — observe both.", "The 171/224 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32017 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32017 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32017?", "a": "The SKF 32017 X is a single-row tapered roller bearing with 85 mm bore, 130 mm outer diameter and 29 mm width (3.346 × 5.118 × 1.142 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 171 kN, C0 224 kN, fatigue load limit Pu 25.5 kN, reference speed 3,800 r/min, limiting speed 4,800 r/min, mass about 1350 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32017 bore code work?", "a": "The last two digits of 32017 are bore code 17, so 17 × 5 = 85 mm bore. The 130 mm OD and 29 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32017 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32017 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32017 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32017 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32017", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32017", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32017" ], "locale_variants": {} }, { "sku": "32018-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32018 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 140, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 208, "static_load_kN": 270, "fatigue_load_limit_kN": 31, "max_rpm": 4300, "reference_speed_rpm": 3600, "limiting_speed_rpm": 4300, "weight_g": 1750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32018 X belongs to the SKF single-row tapered roller range — the 90 mm bore entry in the 32000 series, dimensioned 140 mm OD and 32 mm wide to the ISO 355 boundary plan.The code breaks down as type prefix 3 (tapered roller), series 20 (the low-friction section), and bore code 18 = 90 mm; dimensions 90×140×32 mm therefore match the ISO 355 envelope. In SKF suffix language a bare 32018 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. With C 208 kN and C0 270 kN, the 32018 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 4,300 r/min. Mounting practice for 32018: the rotating cone takes the interference fit (k5 on a 90 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Dimensional interchange map: within the 32000 series at 90 mm bore, the 140 mm OD and 32 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 25.0 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 1750 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Mount the 90 mm bore 32018 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 90 mm bore (140×32 mm) is the low-friction, higher-speed section; it carries less thrust than a 30218 of the same bore, so verify the axial load share before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32018 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Do not mix brands or executions inside one 32018 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The 32018 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 208/270 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32018 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32018 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32018?", "a": "The SKF 32018 X is a single-row tapered roller bearing with 90 mm bore, 140 mm outer diameter and 32 mm width (3.543 × 5.512 × 1.26 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 208 kN, C0 270 kN, fatigue load limit Pu 31 kN, reference speed 3,600 r/min, limiting speed 4,300 r/min, mass about 1750 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32018 bore code work?", "a": "The last two digits of 32018 are bore code 18, so 18 × 5 = 90 mm bore. The 140 mm OD and 32 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32018 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32018 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32018 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32018 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32018", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32018", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32018" ], "locale_variants": {} }, { "sku": "32019-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32019 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 95, "D_mm": 145, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 206, "static_load_kN": 270, "fatigue_load_limit_kN": 30.5, "max_rpm": 4300, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4300, "weight_g": 1850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 95 mm shaft carrying combined load, SKF lists 32019 under catalogue execution SKF 32019 X: one open single-row tapered roller bearing in the low-friction section of the 32000 family.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 20 is the ISO 355 diameter/width series (low-friction section), and the last two digits encode the 95 mm bore; the 145 mm OD and 32 mm width follow the ISO 355 general plan. In SKF suffix language a bare 32019 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 30.5 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.31 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Fit selection follows the rotating ring — interference on a rotating cone — and two 32019 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Operating context for the 95 mm bore: a shaft of this diameter in the large-bore band typically runs between 76000 and 114000 r/min in real machinery, and the 145 mm outside diameter places the housing shoulder at 153 mm outer abutment; the 32 mm width and 1850 g mass together set the shaft critical speed and the housing resonance check for this 32000-series envelope.", "applications": [ "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Mount the 95 mm bore 32019 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 95 mm bore (145×32 mm) is the low-friction, higher-speed section; it carries less thrust than a 30219 of the same bore, so verify the axial load share before swapping.", "Do not mix brands or executions inside one 32019 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32019 mounting error.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 145 mm cup race release as noise within the first running hours.", "The 206/270 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32019 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32019 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32019?", "a": "The SKF 32019 X is a single-row tapered roller bearing with 95 mm bore, 145 mm outer diameter and 32 mm width (3.74 × 5.709 × 1.26 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 206 kN, C0 270 kN, fatigue load limit Pu 30.5 kN, reference speed 3,400 r/min, limiting speed 4,300 r/min, mass about 1850 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32019 bore code work?", "a": "The last two digits of 32019 are bore code 19, so 19 × 5 = 95 mm bore. The 145 mm OD and 32 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32019 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32019 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32019 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32019 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32019", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32019", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32019" ], "locale_variants": {} }, { "sku": "32021-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32021 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 105, "D_mm": 160, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 248, "static_load_kN": 335, "fatigue_load_limit_kN": 37.5, "max_rpm": 3800, "reference_speed_rpm": 3200, "limiting_speed_rpm": 3800, "weight_g": 2450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF 32021 X in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 105 mm shaft, low-friction section, with an open pressed-steel-cage execution and one-direction axial capacity.The code breaks down as type prefix 3 (tapered roller), series 20 (the low-friction section), and bore code 21 = 105 mm; dimensions 105×160×35 mm therefore match the ISO 355 envelope. In SKF suffix language a bare 32021 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Catalogue mass 2450 g for the 105×160×35 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. For a 105 mm shaft the usual cone seat is m6 with an H7 housing when the inner ring rotates; arrange two 32021 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Load system: the 248 kN basic dynamic rating C and 335 kN static rating C0 give a C0/C balance of 1.35, and dividing C by the 105 mm bore yields 2.36 kN per millimetre of journal — a density metric that compares across families; the 37.5 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 105 mm shaft carrying variable duty.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Mount the 105 mm bore 32021 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 105 mm bore (160×35 mm) is the low-friction, higher-speed section; it carries less thrust than a 30221 of the same bore, so verify the axial load share before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32021 mounting error.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32021 mounting error.", "Shaft and housing fillets must clear the bearing chamfer so the 35 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 248/335 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32021 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32021 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32021?", "a": "The SKF 32021 X is a single-row tapered roller bearing with 105 mm bore, 160 mm outer diameter and 35 mm width (4.134 × 6.299 × 1.378 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 248 kN, C0 335 kN, fatigue load limit Pu 37.5 kN, reference speed 3,200 r/min, limiting speed 3,800 r/min, mass about 2450 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32021 bore code work?", "a": "The last two digits of 32021 are bore code 21, so 21 × 5 = 105 mm bore. The 160 mm OD and 35 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32021 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32021 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32021 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32021 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32021", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32021", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32021" ], "locale_variants": {} }, { "sku": "32022-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32022 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 110, "D_mm": 170, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 288, "static_load_kN": 390, "fatigue_load_limit_kN": 40, "max_rpm": 3600, "reference_speed_rpm": 3000, "limiting_speed_rpm": 3600, "weight_g": 3050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32022 is a single-row tapered roller bearing in the ISO 32000 dimension series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 20 is the ISO 355 diameter/width series (low-friction section), and the last two digits encode the 110 mm bore; the 170 mm OD and 38 mm width follow the ISO 355 general plan. In SKF suffix language a bare 32022 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 3,000 r/min reference speed the 30.0 mm-section 32022 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 3,600 r/min as the mechanical ceiling. Mounting practice for 32022: the rotating cone takes the interference fit (m6 on a 110 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Material and manufacturing detail: the 3050 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 32000 ISO envelope, with the pressed-steel cage contributing roughly 92 g of the total; the 110 mm bore is ground to IT5 roundness and the 170 mm OD to IT5 cylindricity, and the 38 mm width tolerance keeps the pair-setting scatter within the ISO preload class.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Mount the 110 mm bore 32022 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 110 mm bore (170×38 mm) is the low-friction, higher-speed section; it carries less thrust than a 30222 of the same bore, so verify the axial load share before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32022 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32022 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Catalogue reference speed and limiting speed are different limits: the 3,000 r/min reference is a thermal criterion under load, while the 3,600 r/min limiting value is the mechanical ceiling — observe both.", "The 288/390 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32022 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32022 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32022?", "a": "The SKF 32022 X is a single-row tapered roller bearing with 110 mm bore, 170 mm outer diameter and 38 mm width (4.331 × 6.693 × 1.496 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 288 kN, C0 390 kN, fatigue load limit Pu 40 kN, reference speed 3,000 r/min, limiting speed 3,600 r/min, mass about 3050 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32022 bore code work?", "a": "The last two digits of 32022 are bore code 22, so 22 × 5 = 110 mm bore. The 170 mm OD and 38 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32022 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32022 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32022 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32022 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32022", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32022", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32022" ], "locale_variants": {} }, { "sku": "32024-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32024 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 120, "D_mm": 180, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 299, "static_load_kN": 415, "fatigue_load_limit_kN": 42.5, "max_rpm": 3400, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3400, "weight_g": 3300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 32024 appears as SKF 32024 X: an open, single-row tapered roller bearing in the low-friction section of the 32000 dimension series, supplied with a pressed-steel cage as standard.Numbering ties the bearing to its envelope: 32024 means tapered-roller type 3, low-friction section series 20, 120 mm bore — which is why the 180×38 mm outline swaps dimensionally with other ISO 355 bearings of the same code. In SKF suffix language a bare 32024 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. With C 299 kN and C0 415 kN, the 32024 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 3,400 r/min. A single 32024 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Operating context for the 120 mm bore: a shaft of this diameter in the xl-bore band typically runs between 96000 and 144000 r/min in real machinery, and the 180 mm outside diameter places the housing shoulder at 188 mm outer abutment; the 38 mm width and 3300 g mass together set the shaft critical speed and the housing resonance check for this 32000-series envelope.", "applications": [ "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At 120 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 320 series at 120 mm bore (180×38 mm) is the low-friction, higher-speed section; it carries less thrust than a 30224 of the same bore, so verify the axial load share before swapping.", "A single 32024 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "A single 32024 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 180 mm cup race release as noise within the first running hours.", "The 299/415 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32024 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32024 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32024?", "a": "The SKF 32024 X is a single-row tapered roller bearing with 120 mm bore, 180 mm outer diameter and 38 mm width (4.724 × 7.087 × 1.496 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 299 kN, C0 415 kN, fatigue load limit Pu 42.5 kN, reference speed 2,800 r/min, limiting speed 3,400 r/min, mass about 3300 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32024 bore code work?", "a": "The last two digits of 32024 are bore code 24, so 24 × 5 = 120 mm bore. The 180 mm OD and 38 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32024 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32024 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32024 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32024 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32024", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32024", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32024" ], "locale_variants": {} }, { "sku": "32026-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32026 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 130, "D_mm": 200, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 388, "static_load_kN": 540, "fatigue_load_limit_kN": 55, "max_rpm": 3000, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3000, "weight_g": 4950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 130 mm shaft carrying combined load, SKF lists 32026 under catalogue execution SKF 32026 X: one open single-row tapered roller bearing in the low-friction section of the 32000 family.The code breaks down as type prefix 3 (tapered roller), series 20 (the low-friction section), and bore code 26 = 130 mm; dimensions 130×200×45 mm therefore match the ISO 355 envelope. In SKF suffix language a bare 32026 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 1.39 (static 540 kN against dynamic 388 kN), typical of a tapered roller sized for axial capacity, and the 55 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 32026 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Journal and housing interface: the 130 mm bore takes a m6 shaft seat (upper deviation ~0.260 mm for this diameter range) and the 200 mm outside diameter pairs with an H7 housing bore tolerance band of 200.000/200.020 mm; the 45 mm width defines the shoulder depth, and the 4950 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "At 130 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 320 series at 130 mm bore (200×45 mm) is the low-friction, higher-speed section; it carries less thrust than a 30226 of the same bore, so verify the axial load share before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32026 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32026 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The 4950 g mass and 45 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 32026.", "The 388/540 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32026 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32026 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32026?", "a": "The SKF 32026 X is a single-row tapered roller bearing with 130 mm bore, 200 mm outer diameter and 45 mm width (5.118 × 7.874 × 1.772 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 388 kN, C0 540 kN, fatigue load limit Pu 55 kN, reference speed 2,400 r/min, limiting speed 3,000 r/min, mass about 4950 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32026 bore code work?", "a": "The last two digits of 32026 are bore code 26, so 26 × 5 = 130 mm bore. The 200 mm OD and 45 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32026 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32026 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32026 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32026 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32026", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32026", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32026" ], "locale_variants": {} }, { "sku": "32028-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32028 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 140, "D_mm": 210, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 404, "static_load_kN": 585, "fatigue_load_limit_kN": 58.5, "max_rpm": 2800, "reference_speed_rpm": 2400, "limiting_speed_rpm": 2800, "weight_g": 5250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF 32028 X in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 140 mm shaft, low-friction section, with an open pressed-steel-cage execution and one-direction axial capacity.Digit by digit, 32028 reads as bearing type 3 (single-row tapered roller), low-friction section series 20, and bore reference 28 resolving to 140 mm; 210 mm OD and 45 mm width are the matching ISO 355 boundary values. In SKF suffix language a bare 32028 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Catalogue mass 5250 g for the 140×210×45 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. For a 140 mm shaft the usual cone seat is m6 with an H7 housing when the inner ring rotates; arrange two 32028 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Load system: the 404 kN basic dynamic rating C and 585 kN static rating C0 give a C0/C balance of 1.45, and dividing C by the 140 mm bore yields 2.89 kN per millimetre of journal — a density metric that compares across families; the 58.5 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 140 mm shaft carrying variable duty.", "applications": [ "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "At 140 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 320 series at 140 mm bore (210×45 mm) is the low-friction, higher-speed section; it carries less thrust than a 30228 of the same bore, so verify the axial load share before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32028 mounting error.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32028 mounting error.", "Shaft and housing fillets must clear the bearing chamfer so the 45 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 404/585 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32028 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32028 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32028?", "a": "The SKF 32028 X is a single-row tapered roller bearing with 140 mm bore, 210 mm outer diameter and 45 mm width (5.512 × 8.268 × 1.772 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 404 kN, C0 585 kN, fatigue load limit Pu 58.5 kN, reference speed 2,400 r/min, limiting speed 2,800 r/min, mass about 5250 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32028 bore code work?", "a": "The last two digits of 32028 are bore code 28, so 28 × 5 = 140 mm bore. The 210 mm OD and 45 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32028 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32028 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32028 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32028 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32028", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32028", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32028" ], "locale_variants": {} }, { "sku": "32030-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32030 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 150, "D_mm": 225, "B_mm": 48, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 456, "static_load_kN": 655, "fatigue_load_limit_kN": 65.5, "max_rpm": 2600, "reference_speed_rpm": 2200, "limiting_speed_rpm": 2600, "weight_g": 6400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 32030 X is a 150×225×48 mm single-row tapered roller bearing — the low-friction section entry in the 32000 series, with an asymmetric raceway cut for thrust capacity and separable mounting.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 20 is the ISO 355 diameter/width series (low-friction section), and the last two digits encode the 150 mm bore; the 225 mm OD and 48 mm width follow the ISO 355 general plan. In SKF suffix language a bare 32030 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. With C 456 kN and C0 655 kN, the 32030 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 2,600 r/min. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 32030 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Cross-section geometry: the 37.5 mm half-section ((225−150)/2) of this 32000-series unit places the roller large-end pitch diameter at roughly 187 mm, and the 48 mm axial width is split between cone (26 mm) and cup rib (22 mm) — a geometry that sets the contact angle and, with the 6400 g rotating cone mass, the critical speed at which cage-roller imbalance begins.", "applications": [ "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "At 150 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 320 series at 150 mm bore (225×48 mm) is the low-friction, higher-speed section; it carries less thrust than a 30230 of the same bore, so verify the axial load share before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32030 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32030 mounting error.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 456/655 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32030 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32030 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32030?", "a": "The SKF 32030 X is a single-row tapered roller bearing with 150 mm bore, 225 mm outer diameter and 48 mm width (5.906 × 8.858 × 1.89 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 456 kN, C0 655 kN, fatigue load limit Pu 65.5 kN, reference speed 2,200 r/min, limiting speed 2,600 r/min, mass about 6400 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32030 bore code work?", "a": "The last two digits of 32030 are bore code 30, so 30 × 5 = 150 mm bore. The 225 mm OD and 48 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32030 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32030 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32030 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32030 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32030", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32030", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32030" ], "locale_variants": {} }, { "sku": "32032", "brand": "SKF", "manufacturer_designation": "SKF 32032 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 160, "D_mm": 240, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 532, "static_load_kN": 780, "fatigue_load_limit_kN": 76.5, "max_rpm": 2400, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2400, "weight_g": 7800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32032 X belongs to the SKF single-row tapered roller range — the 160 mm bore entry in the 32000 series, dimensioned 240 mm OD and 51 mm wide to the ISO 355 boundary plan.Numbering ties the bearing to its envelope: 32032 means tapered-roller type 3, low-friction section series 20, 160 mm bore — which is why the 240×51 mm outline swaps dimensionally with other ISO 355 bearings of the same code. In SKF suffix language a bare 32032 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 1.47 (static 780 kN against dynamic 532 kN), typical of a tapered roller sized for axial capacity, and the 76.5 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. For a 160 mm shaft the usual cone seat is m6 with an H7 housing when the inner ring rotates; arrange two 32032 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Speed envelope and thermal behaviour: at 2,000 r/min thermal reference, the 160 mm bore shaft runs at a dn of 320k, and the 40.0 mm section dissipates heat through the cup-to-housing contact path; the 2,400 r/min mechanical ceiling reflects cage strength, and the 7800 g spinning cone contributes gyroscopic moment under rapid speed reversal.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At 160 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 320 series at 160 mm bore (240×51 mm) is the low-friction, higher-speed section; it carries less thrust than a 30232 of the same bore, so verify the axial load share before swapping.", "A single 32032 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Setting is a design value, not an assembly feel: excessive preload in the 32032 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Open 32032 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 532/780 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32032 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32032 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32032?", "a": "The SKF 32032 X is a single-row tapered roller bearing with 160 mm bore, 240 mm outer diameter and 51 mm width (6.299 × 9.449 × 2.008 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 532 kN, C0 780 kN, fatigue load limit Pu 76.5 kN, reference speed 2,000 r/min, limiting speed 2,400 r/min, mass about 7800 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32032 bore code work?", "a": "The last two digits of 32032 are bore code 32, so 32 × 5 = 160 mm bore. The 240 mm OD and 51 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32032 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32032 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32032 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32032 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32032", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32032" ], "locale_variants": {} }, { "sku": "32034", "brand": "SKF", "manufacturer_designation": "SKF 32034 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 170, "D_mm": 260, "B_mm": 57, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 625, "static_load_kN": 915, "fatigue_load_limit_kN": 88, "max_rpm": 2200, "reference_speed_rpm": 1900, "limiting_speed_rpm": 2200, "weight_g": 10500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32034 (SKF 32034 X) is the low-friction section tapered roller choice for a 170 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 260×57 mm ISO 355 envelope.The code breaks down as type prefix 3 (tapered roller), series 20 (the low-friction section), and bore code 34 = 170 mm; dimensions 170×260×57 mm therefore match the ISO 355 envelope. In SKF suffix language a bare 32034 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Catalogue mass 10500 g for the 170×260×57 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Fit selection follows the rotating ring — interference on a rotating cone — and two 32034 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Material and manufacturing detail: the 10500 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 32000 ISO envelope, with the pressed-steel cage contributing roughly 315 g of the total; the 170 mm bore is ground to IT5 roundness and the 260 mm OD to IT5 cylindricity, and the 57 mm width tolerance keeps the pair-setting scatter within the ISO preload class.", "applications": [ "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "At 170 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 320 series at 170 mm bore (260×57 mm) is the low-friction, higher-speed section; it carries less thrust than a 30234 of the same bore, so verify the axial load share before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32034 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "At the 625 kN rating of 32034, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 2,200 r/min speed end and heavier preload only where moment stiffness dominates.", "Catalogue reference speed and limiting speed are different limits: the 1,900 r/min reference is a thermal criterion under load, while the 2,200 r/min limiting value is the mechanical ceiling — observe both.", "The 625/915 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32034 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32034 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32034?", "a": "The SKF 32034 X is a single-row tapered roller bearing with 170 mm bore, 260 mm outer diameter and 57 mm width (6.693 × 10.236 × 2.244 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 625 kN, C0 915 kN, fatigue load limit Pu 88 kN, reference speed 1,900 r/min, limiting speed 2,200 r/min, mass about 10500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32034 bore code work?", "a": "The last two digits of 32034 are bore code 34, so 34 × 5 = 170 mm bore. The 260 mm OD and 57 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32034 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32034 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32034 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32034 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32034", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32034" ], "locale_variants": {} }, { "sku": "32036", "brand": "SKF", "manufacturer_designation": "SKF 32036 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 180, "D_mm": 280, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 793, "static_load_kN": 1160, "fatigue_load_limit_kN": 110, "max_rpm": 2200, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2200, "weight_g": 14000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32036 is a single-row tapered roller bearing in the ISO 32000 dimension series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Digit by digit, 32036 reads as bearing type 3 (single-row tapered roller), low-friction section series 20, and bore reference 36 resolving to 180 mm; 280 mm OD and 64 mm width are the matching ISO 355 boundary values. In SKF suffix language a bare 32036 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Speed planning uses two different ceilings: 1,700 r/min thermal reference and 2,200 r/min mechanical limiting speed. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 32036 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Operating context for the 180 mm bore: a shaft of this diameter in the xl-bore band typically runs between 144000 and 216000 r/min in real machinery, and the 280 mm outside diameter places the housing shoulder at 288 mm outer abutment; the 64 mm width and 14000 g mass together set the shaft critical speed and the housing resonance check for this 32000-series envelope.", "applications": [ "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At 180 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 320 series at 180 mm bore (280×64 mm) is the low-friction, higher-speed section; it carries less thrust than a 30236 of the same bore, so verify the axial load share before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32036 mounting error.", "Do not mix brands or executions inside one 32036 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 280 mm cup race release as noise within the first running hours.", "The 793/1160 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32036 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32036 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32036?", "a": "The SKF 32036 X is a single-row tapered roller bearing with 180 mm bore, 280 mm outer diameter and 64 mm width (7.087 × 11.024 × 2.52 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 793 kN, C0 1160 kN, fatigue load limit Pu 110 kN, reference speed 1,700 r/min, limiting speed 2,200 r/min, mass about 14000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32036 bore code work?", "a": "The last two digits of 32036 are bore code 36, so 36 × 5 = 180 mm bore. The 280 mm OD and 64 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32036 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32036 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32036 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32036 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32036", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32036" ], "locale_variants": {} }, { "sku": "32038", "brand": "SKF", "manufacturer_designation": "SKF 32038 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 190, "D_mm": 290, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 806, "static_load_kN": 1200, "fatigue_load_limit_kN": 112, "max_rpm": 2000, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2000, "weight_g": 15000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 32038 appears as SKF 32038 X: an open, single-row tapered roller bearing in the low-friction section of the 32000 dimension series, supplied with a pressed-steel cage as standard.On the SKF nameplate, 32038 follows the ISO 355 convention: 3 for the tapered-roller type, 20 for the low-friction section, final digits 38 for the 190 mm bore. In SKF suffix language a bare 32038 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 112 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.49 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Because the contact line is tapered, one 32038 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 190 mm shaft typically takes a m6 seat with an H7 housing bore. Journal and housing interface: the 190 mm bore takes a m6 shaft seat (upper deviation ~0.380 mm for this diameter range) and the 290 mm outside diameter pairs with an H7 housing bore tolerance band of 290.000/290.020 mm; the 64 mm width defines the shoulder depth, and the 15000 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations.", "applications": [ "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "At 190 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 320 series at 190 mm bore (290×64 mm) is the low-friction, higher-speed section; it carries less thrust than a 30238 of the same bore, so verify the axial load share before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 32038 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32038 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The 15000 g mass and 64 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 32038.", "The 806/1200 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32038 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32038 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32038?", "a": "The SKF 32038 X is a single-row tapered roller bearing with 190 mm bore, 290 mm outer diameter and 64 mm width (7.48 × 11.417 × 2.52 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 806 kN, C0 1200 kN, fatigue load limit Pu 112 kN, reference speed 1,600 r/min, limiting speed 2,000 r/min, mass about 15000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32038 bore code work?", "a": "The last two digits of 32038 are bore code 38, so 38 × 5 = 190 mm bore. The 290 mm OD and 64 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32038 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32038 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32038 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32038 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32038", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32038" ], "locale_variants": {} }, { "sku": "32040", "brand": "SKF", "manufacturer_designation": "SKF 32040 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 200, "D_mm": 310, "B_mm": 70, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 800, "static_load_kN": 1370, "fatigue_load_limit_kN": 127, "max_rpm": 1900, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1900, "weight_g": 19000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 200 mm shaft carrying combined load, SKF lists 32040 under catalogue execution SKF 32040 X: one open single-row tapered roller bearing in the low-friction section of the 32000 family.Numbering ties the bearing to its envelope: 32040 means tapered-roller type 3, low-friction section series 20, 200 mm bore — which is why the 310×70 mm outline swaps dimensionally with other ISO 355 bearings of the same code. In SKF suffix language a bare 32040 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Catalogue mass 19000 g for the 200×310×70 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 32040 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Dimensional interchange map: within the 32000 series at 200 mm bore, the 310 mm OD and 70 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 55.0 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 19000 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "At 200 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 320 series at 200 mm bore (310×70 mm) is the low-friction, higher-speed section; it carries less thrust than a 30240 of the same bore, so verify the axial load share before swapping.", "A single 32040 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32040 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The 32040 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 800/1370 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32040 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32040 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32040?", "a": "The SKF 32040 X is a single-row tapered roller bearing with 200 mm bore, 310 mm outer diameter and 70 mm width (7.874 × 12.205 × 2.756 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 800 kN, C0 1370 kN, fatigue load limit Pu 127 kN, reference speed 1,400 r/min, limiting speed 1,900 r/min, mass about 19000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32040 bore code work?", "a": "The last two digits of 32040 are bore code 40, so 40 × 5 = 200 mm bore. The 310 mm OD and 70 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32040 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32040 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32040 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32040 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32040", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32040" ], "locale_variants": {} }, { "sku": "32044", "brand": "SKF", "manufacturer_designation": "SKF 32044 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 220, "D_mm": 340, "B_mm": 76, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 955, "static_load_kN": 1660, "fatigue_load_limit_kN": 150, "max_rpm": 1700, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1700, "weight_g": 24500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 32044 X is a 220×340×76 mm single-row tapered roller bearing — the low-friction section entry in the 32000 series, with an asymmetric raceway cut for thrust capacity and separable mounting.Digit by digit, 32044 reads as bearing type 3 (single-row tapered roller), low-friction section series 20, and bore reference 44 resolving to 220 mm; 340 mm OD and 76 mm width are the matching ISO 355 boundary values. In SKF suffix language a bare 32044 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 150 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.74 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Mounting practice for 32044: the rotating cone takes the interference fit (m6 on a 220 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Speed envelope and thermal behaviour: at 1,300 r/min thermal reference, the 220 mm bore shaft runs at a dn of 286k, and the 60.0 mm section dissipates heat through the cup-to-housing contact path; the 1,700 r/min mechanical ceiling reflects cage strength, and the 24500 g spinning cone contributes gyroscopic moment under rapid speed reversal.", "applications": [ "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At 220 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 320 series at 220 mm bore (340×76 mm) is the low-friction, higher-speed section; it carries less thrust than a 30244 of the same bore, so verify the axial load share before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32044 mounting error.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32044 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Open 32044 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 955/1660 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32044 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32044 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32044?", "a": "The SKF 32044 X is a single-row tapered roller bearing with 220 mm bore, 340 mm outer diameter and 76 mm width (8.661 × 13.386 × 2.992 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 955 kN, C0 1660 kN, fatigue load limit Pu 150 kN, reference speed 1,300 r/min, limiting speed 1,700 r/min, mass about 24500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32044 bore code work?", "a": "The last two digits of 32044 are bore code 44, so 44 × 5 = 220 mm bore. The 340 mm OD and 76 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32044 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32044 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32044 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32044 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32044", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32044" ], "locale_variants": {} }, { "sku": "32048", "brand": "SKF", "manufacturer_designation": "SKF 32048 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 240, "D_mm": 360, "B_mm": 76, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 989, "static_load_kN": 1800, "fatigue_load_limit_kN": 156, "max_rpm": 1600, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1600, "weight_g": 26500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32048 (SKF 32048 X) is the low-friction section tapered roller choice for a 240 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 360×76 mm ISO 355 envelope.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 20 is the ISO 355 diameter/width series (low-friction section), and the last two digits encode the 240 mm bore; the 360 mm OD and 76 mm width follow the ISO 355 general plan. In SKF suffix language a bare 32048 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 1,200 r/min reference speed the 60.0 mm-section 32048 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 1,600 r/min as the mechanical ceiling. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 32048 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Operating context for the 240 mm bore: a shaft of this diameter in the xl-bore band typically runs between 192000 and 288000 r/min in real machinery, and the 360 mm outside diameter places the housing shoulder at 368 mm outer abutment; the 76 mm width and 26500 g mass together set the shaft critical speed and the housing resonance check for this 32000-series envelope.", "applications": [ "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At 240 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 320 series at 240 mm bore (360×76 mm) is the low-friction, higher-speed section; it carries less thrust than a 30248 of the same bore, so verify the axial load share before swapping.", "At the 989 kN rating of 32048, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 1,600 r/min speed end and heavier preload only where moment stiffness dominates.", "Setting is a design value, not an assembly feel: excessive preload in the 32048 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 360 mm cup race release as noise within the first running hours.", "The 989/1800 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32048 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32048 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32048?", "a": "The SKF 32048 X is a single-row tapered roller bearing with 240 mm bore, 360 mm outer diameter and 76 mm width (9.449 × 14.173 × 2.992 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 989 kN, C0 1800 kN, fatigue load limit Pu 156 kN, reference speed 1,200 r/min, limiting speed 1,600 r/min, mass about 26500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32048 bore code work?", "a": "The last two digits of 32048 are bore code 48, so 48 × 5 = 240 mm bore. The 360 mm OD and 76 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32048 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32048 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32048 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32048 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32048", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32048" ], "locale_variants": {} }, { "sku": "32052", "brand": "SKF", "manufacturer_designation": "SKF 32052 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 260, "D_mm": 400, "B_mm": 87, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1241, "static_load_kN": 2200, "fatigue_load_limit_kN": 190, "max_rpm": 1400, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1400, "weight_g": 38000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 32052 appears as SKF 32052 X: an open, single-row tapered roller bearing in the low-friction section of the 32000 dimension series, supplied with a pressed-steel cage as standard.Digit by digit, 32052 reads as bearing type 3 (single-row tapered roller), low-friction section series 20, and bore reference 52 resolving to 260 mm; 400 mm OD and 87 mm width are the matching ISO 355 boundary values. In SKF suffix language a bare 32052 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 70.0 mm radial section height ((400−260)/2) and 38000 g catalogue mass frame a 260 mm bore bearing rated at 1241 kN C — roughly 4.77 kN of dynamic capacity per millimetre of bore before application factors. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 32052 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Dimensional interchange map: within the 32000 series at 260 mm bore, the 400 mm OD and 87 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 70.0 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 38000 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "At 260 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 320 series at 260 mm bore (400×87 mm) is the low-friction, higher-speed section; it carries less thrust than a 30252 of the same bore, so verify the axial load share before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32052 mounting error.", "At the 1241 kN rating of 32052, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 1,400 r/min speed end and heavier preload only where moment stiffness dominates.", "The 32052 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 1241/2200 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32052 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32052 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32052?", "a": "The SKF 32052 X is a single-row tapered roller bearing with 260 mm bore, 400 mm outer diameter and 87 mm width (10.236 × 15.748 × 3.425 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1241 kN, C0 2200 kN, fatigue load limit Pu 190 kN, reference speed 1,100 r/min, limiting speed 1,400 r/min, mass about 38000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32052 bore code work?", "a": "The last two digits of 32052 are bore code 52, so 52 × 5 = 260 mm bore. The 400 mm OD and 87 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32052 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32052 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32052 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32052 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32052", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32052" ], "locale_variants": {} }, { "sku": "32056", "brand": "SKF", "manufacturer_designation": "SKF 32056 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 280, "D_mm": 420, "B_mm": 87, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1288, "static_load_kN": 2360, "fatigue_load_limit_kN": 200, "max_rpm": 1300, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1300, "weight_g": 40500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF 32056 X in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 280 mm shaft, low-friction section, with an open pressed-steel-cage execution and one-direction axial capacity.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 20 is the ISO 355 diameter/width series (low-friction section), and the last two digits encode the 280 mm bore; the 420 mm OD and 87 mm width follow the ISO 355 general plan. In SKF suffix language a bare 32056 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. With C 1288 kN and C0 2360 kN, the 32056 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 1,300 r/min. Fit selection follows the rotating ring — interference on a rotating cone — and two 32056 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Speed envelope and thermal behaviour: at 1,000 r/min thermal reference, the 280 mm bore shaft runs at a dn of 280k, and the 70.0 mm section dissipates heat through the cup-to-housing contact path; the 1,300 r/min mechanical ceiling reflects cage strength, and the 40500 g spinning cone contributes gyroscopic moment under rapid speed reversal.", "applications": [ "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At 280 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 320 series at 280 mm bore (420×87 mm) is the low-friction, higher-speed section; it carries less thrust than a 30256 of the same bore, so verify the axial load share before swapping.", "At the 1288 kN rating of 32056, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 1,300 r/min speed end and heavier preload only where moment stiffness dominates.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32056 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Open 32056 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 1288/2360 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32056 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32056 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32056?", "a": "The SKF 32056 X is a single-row tapered roller bearing with 280 mm bore, 420 mm outer diameter and 87 mm width (11.024 × 16.535 × 3.425 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1288 kN, C0 2360 kN, fatigue load limit Pu 200 kN, reference speed 1,000 r/min, limiting speed 1,300 r/min, mass about 40500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32056 bore code work?", "a": "The last two digits of 32056 are bore code 56, so 56 × 5 = 280 mm bore. The 420 mm OD and 87 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32056 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32056 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32056 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32056 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32056", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32056" ], "locale_variants": {} }, { "sku": "320-22", "brand": "SKF", "manufacturer_designation": "SKF 320/22 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 22, "D_mm": 44, "B_mm": 15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 30.9, "static_load_kN": 29, "fatigue_load_limit_kN": 2.85, "max_rpm": 15000, "reference_speed_rpm": 13000, "limiting_speed_rpm": 15000, "weight_g": 100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 320/22 X is a 22×44×15 mm single-row tapered roller bearing — the low-friction section entry in the 32000 series, with an asymmetric raceway cut for thrust capacity and separable mounting.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 20 is the ISO 355 diameter/width series (low-friction section), and the last two digits encode the 22 mm bore; the 44 mm OD and 15 mm width follow the ISO 355 general plan. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Catalogue mass 100 g for the 22×44×15 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 320 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Operating context for the 22 mm bore: a shaft of this diameter in the small-bore band typically runs between 17600 and 26400 r/min in real machinery, and the 44 mm outside diameter places the housing shoulder at 52 mm outer abutment; the 15 mm width and 100 g mass together set the shaft critical speed and the housing resonance check for this 32000-series envelope.", "applications": [ "agricultural implement hubs", "small conveyor drive pulleys", "power-tool gear heads", "small automotive wheel hubs and trailer axles" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At a 22 mm bore the thin cone and cup are easily distorted by an over-tight shaft nut; check seat runout (target Ra ≤ 0.8 µm) and torque the locknut progressively — a pinched 320 shows up as gearbox vibration long before it fails.", "The 320 series at 22 mm bore (44×15 mm) is the low-friction, higher-speed section; it carries less thrust than a 30220 of the same bore, so verify the axial load share before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 320 mounting error.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 320 mounting error.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 30.9/29 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 320 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 320/22 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 320?", "a": "The SKF 320/22 X is a single-row tapered roller bearing with 22 mm bore, 44 mm outer diameter and 15 mm width (0.866 × 1.732 × 0.591 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 30.9 kN, C0 29 kN, fatigue load limit Pu 2.85 kN, reference speed 13,000 r/min, limiting speed 15,000 r/min, mass about 100 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 320 bore code work?", "a": "Non-standard bore sizes like 320 give the bore directly in millimetres after the slash, so 20 here means a 22 mm bore rather than a code × 5 value. The 44 mm OD and 15 mm width still follow the ISO 355 dimension-series plan for the 320 family." }, { "q": "What do the 320 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 320 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 320 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 320 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "320-22X", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "320-28X", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "320-32X", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "320-22", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "320-22" ], "locale_variants": {} }, { "sku": "320-28", "brand": "SKF", "manufacturer_designation": "SKF 320/28 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 28, "D_mm": 52, "B_mm": 16, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 39, "static_load_kN": 38, "fatigue_load_limit_kN": 4, "max_rpm": 13000, "reference_speed_rpm": 10000, "limiting_speed_rpm": 13000, "weight_g": 140, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 320/28 X is a 28×52×16 mm single-row tapered roller bearing — the low-friction section entry in the 32000 series, with an asymmetric raceway cut for thrust capacity and separable mounting.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 20 is the ISO 355 diameter/width series (low-friction section), and the last two digits encode the 28 mm bore; the 52 mm OD and 16 mm width follow the ISO 355 general plan. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Catalogue mass 140 g for the 28×52×16 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 320 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Dimensional interchange map: within the 32000 series at 28 mm bore, the 52 mm OD and 16 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 12.0 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 140 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "On this 28 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 320 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 28 mm bore (52×16 mm) is the low-friction, higher-speed section; it carries less thrust than a 30220 of the same bore, so verify the axial load share before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 320 mounting error.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 320 mounting error.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 39/38 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 320 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 320/28 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 320?", "a": "The SKF 320/28 X is a single-row tapered roller bearing with 28 mm bore, 52 mm outer diameter and 16 mm width (1.102 × 2.047 × 0.63 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 39 kN, C0 38 kN, fatigue load limit Pu 4 kN, reference speed 10,000 r/min, limiting speed 13,000 r/min, mass about 140 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 320 bore code work?", "a": "Non-standard bore sizes like 320 give the bore directly in millimetres after the slash, so 20 here means a 28 mm bore rather than a code × 5 value. The 52 mm OD and 16 mm width still follow the ISO 355 dimension-series plan for the 320 family." }, { "q": "What do the 320 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 320 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 320 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 320 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "320-22X", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "320-28X", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "320-32X", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "320-28", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "320-28" ], "locale_variants": {} }, { "sku": "320-32", "brand": "SKF", "manufacturer_designation": "SKF 320/32 X", "series": "32000-series", "type": "tapered_roller", "d_mm": 32, "D_mm": 58, "B_mm": 17, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 45.1, "static_load_kN": 46.5, "fatigue_load_limit_kN": 4.8, "max_rpm": 11000, "reference_speed_rpm": 9000, "limiting_speed_rpm": 11000, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 320/32 X is a 32×58×17 mm single-row tapered roller bearing — the low-friction section entry in the 32000 series, with an asymmetric raceway cut for thrust capacity and separable mounting.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 20 is the ISO 355 diameter/width series (low-friction section), and the last two digits encode the 32 mm bore; the 58 mm OD and 17 mm width follow the ISO 355 general plan. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Catalogue mass 190 g for the 32×58×17 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 320 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Speed envelope and thermal behaviour: at 9,000 r/min thermal reference, the 32 mm bore shaft runs at a dn of 288k, and the 13.0 mm section dissipates heat through the cup-to-housing contact path; the 11,000 r/min mechanical ceiling reflects cage strength, and the 190 g spinning cone contributes gyroscopic moment under rapid speed reversal.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "On this 32 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 320 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 32 mm bore (58×17 mm) is the low-friction, higher-speed section; it carries less thrust than a 30220 of the same bore, so verify the axial load share before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 320 mounting error.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 320 mounting error.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 45.1/46.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 320 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 320/32 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 320?", "a": "The SKF 320/32 X is a single-row tapered roller bearing with 32 mm bore, 58 mm outer diameter and 17 mm width (1.26 × 2.283 × 0.669 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 45.1 kN, C0 46.5 kN, fatigue load limit Pu 4.8 kN, reference speed 9,000 r/min, limiting speed 11,000 r/min, mass about 190 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 320 bore code work?", "a": "Non-standard bore sizes like 320 give the bore directly in millimetres after the slash, so 20 here means a 32 mm bore rather than a code × 5 value. The 58 mm OD and 17 mm width still follow the ISO 355 dimension-series plan for the 320 family." }, { "q": "What do the 320 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 20 is the ISO 355 series (low-friction section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 320 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 320 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 320 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "320-22X", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "320-28X", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "320-32X", "equiv_brand": "NTN", "level": "partial", "note": "Same 32×58×17 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "320-32", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "320-32" ], "locale_variants": {} }, { "sku": "32205-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32205", "series": "32200-series", "type": "tapered_roller", "d_mm": 25, "D_mm": 52, "B_mm": 19.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 50.4, "static_load_kN": 45.5, "fatigue_load_limit_kN": 4.9, "max_rpm": 13000, "reference_speed_rpm": 11000, "limiting_speed_rpm": 13000, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 32205 is a 25×52×19.25 mm single-row tapered roller bearing — the heavy section entry in the 32200 series, with an asymmetric raceway cut for thrust capacity and separable mounting.Numbering ties the bearing to its envelope: 32205 means tapered-roller type 3, heavy section series 22, 25 mm bore — which is why the 52×19.25 mm outline swaps dimensionally with other ISO 355 bearings of the same code. In SKF suffix language a bare 32205 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Speed planning uses two different ceilings: 11,000 r/min thermal reference and 13,000 r/min mechanical limiting speed. Because the contact line is tapered, one 32205 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 25 mm shaft typically takes a k5 seat with an H7 housing bore. Operating context for the 25 mm bore: a shaft of this diameter in the small-bore band typically runs between 20000 and 30000 r/min in real machinery, and the 52 mm outside diameter places the housing shoulder at 60 mm outer abutment; the 19.25 mm width and 190 g mass together set the shaft critical speed and the housing resonance check for this 32200-series envelope.", "applications": [ "light-duty gearbox input/output shafts", "electric-motor pinion shafts", "steering knuckles and small differentials", "agricultural implement hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "At a 25 mm bore the thin cone and cup are easily distorted by an over-tight shaft nut; check seat runout (target Ra ≤ 0.8 µm) and torque the locknut progressively — a pinched 32205 shows up as gearbox vibration long before it fails.", "The 322 series at 25 mm bore (52×19.25 mm) is a wider, higher-capacity section than 30205; do not substitute without re-checking shaft shoulder diameters and pair setting.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32205 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "At the 50.4 kN rating of 32205, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 13,000 r/min speed end and heavier preload only where moment stiffness dominates.", "Shaft and housing fillets must clear the bearing chamfer so the 19.25 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 50.4/45.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32205 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32205 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32205?", "a": "The SKF 32205 is a single-row tapered roller bearing with 25 mm bore, 52 mm outer diameter and 19.25 mm width (0.984 × 2.047 × 0.758 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 50.4 kN, C0 45.5 kN, fatigue load limit Pu 4.9 kN, reference speed 11,000 r/min, limiting speed 13,000 r/min, mass about 190 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32205 bore code work?", "a": "The last two digits of 32205 are bore code 05, so 05 × 5 = 25 mm bore. The 52 mm OD and 19.25 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32205 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32205 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32205 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32205 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32205", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32205-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32205", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32205" ], "locale_variants": {} }, { "sku": "32206-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32206", "series": "32200-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 62, "B_mm": 21.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 61.8, "static_load_kN": 57, "fatigue_load_limit_kN": 6.3, "max_rpm": 11000, "reference_speed_rpm": 9000, "limiting_speed_rpm": 11000, "weight_g": 290, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 32206 appears as SKF 32206: an open, single-row tapered roller bearing in the heavy section of the 32200 dimension series, supplied with a pressed-steel cage as standard.On the SKF nameplate, 32206 follows the ISO 355 convention: 3 for the tapered-roller type, 22 for the heavy section, final digits 06 for the 30 mm bore. In SKF suffix language a bare 32206 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. With C 61.8 kN and C0 57 kN, the 32206 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 11,000 r/min. For a 30 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 32206 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Cross-section geometry: the 16.0 mm half-section ((62−30)/2) of this 32200-series unit places the roller large-end pitch diameter at roughly 46 mm, and the 21.25 mm axial width is split between cone (12 mm) and cup rib (10 mm) — a geometry that sets the contact angle and, with the 290 g rotating cone mass, the critical speed at which cage-roller imbalance begins.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "On this 30 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 32206 pair heats, loses setting control and smears the roller-rib contact.", "The 322 series at 30 mm bore (62×21.25 mm) is a wider, higher-capacity section than 30206; do not substitute without re-checking shaft shoulder diameters and pair setting.", "Setting is a design value, not an assembly feel: excessive preload in the 32206 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32206 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Catalogue reference speed and limiting speed are different limits: the 9,000 r/min reference is a thermal criterion under load, while the 11,000 r/min limiting value is the mechanical ceiling — observe both.", "The 61.8/57 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32206 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32206 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32206?", "a": "The SKF 32206 is a single-row tapered roller bearing with 30 mm bore, 62 mm outer diameter and 21.25 mm width (1.181 × 2.441 × 0.837 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 61.8 kN, C0 57 kN, fatigue load limit Pu 6.3 kN, reference speed 9,000 r/min, limiting speed 11,000 r/min, mass about 290 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32206 bore code work?", "a": "The last two digits of 32206 are bore code 06, so 06 × 5 = 30 mm bore. The 62 mm OD and 21.25 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32206 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32206 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32206 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32206 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32206", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32206-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 30×62×21.25 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "32206", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32206" ], "locale_variants": {} }, { "sku": "32207-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32207", "series": "32200-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 72, "B_mm": 24.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 81.2, "static_load_kN": 78, "fatigue_load_limit_kN": 8.5, "max_rpm": 9500, "reference_speed_rpm": 8000, "limiting_speed_rpm": 9500, "weight_g": 440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32207 belongs to the SKF single-row tapered roller range — the 35 mm bore entry in the 32200 series, dimensioned 72 mm OD and 24.25 mm wide to the ISO 355 boundary plan.The code breaks down as type prefix 3 (tapered roller), series 22 (the heavy section), and bore code 07 = 35 mm; dimensions 35×72×24.25 mm therefore match the ISO 355 envelope. In SKF suffix language a bare 32207 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 8.5 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 0.96 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Mounting practice for 32207: the rotating cone takes the interference fit (k5 on a 35 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Journal and housing interface: the 35 mm bore takes a k5 shaft seat (upper deviation ~0.070 mm for this diameter range) and the 72 mm outside diameter pairs with an H7 housing bore tolerance band of 72.000/72.020 mm; the 24.25 mm width defines the shoulder depth, and the 440 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "On this 35 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 32207 pair heats, loses setting control and smears the roller-rib contact.", "The 322 series at 35 mm bore (72×24.25 mm) is a wider, higher-capacity section than 30207; do not substitute without re-checking shaft shoulder diameters and pair setting.", "A single 32207 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Do not mix brands or executions inside one 32207 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The 32207 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 81.2/78 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32207 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32207 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32207?", "a": "The SKF 32207 is a single-row tapered roller bearing with 35 mm bore, 72 mm outer diameter and 24.25 mm width (1.378 × 2.835 × 0.955 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 81.2 kN, C0 78 kN, fatigue load limit Pu 8.5 kN, reference speed 8,000 r/min, limiting speed 9,500 r/min, mass about 440 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32207 bore code work?", "a": "The last two digits of 32207 are bore code 07, so 07 × 5 = 35 mm bore. The 72 mm OD and 24.25 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32207 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32207 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32207 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32207 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32207", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32207-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 35×72×24.25 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "32207", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32207" ], "locale_variants": {} }, { "sku": "32208-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32208", "series": "32200-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 80, "B_mm": 24.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 91.6, "static_load_kN": 86.5, "fatigue_load_limit_kN": 9.8, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500, "weight_g": 530, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 40 mm shaft carrying combined load, SKF lists 32208 under catalogue execution SKF 32208: one open single-row tapered roller bearing in the heavy section of the 32200 family.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 22 is the ISO 355 diameter/width series (heavy section), and the last two digits encode the 40 mm bore; the 80 mm OD and 24.75 mm width follow the ISO 355 general plan. In SKF suffix language a bare 32208 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 0.94 (static 86.5 kN against dynamic 91.6 kN), typical of a tapered roller sized for axial capacity, and the 9.8 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Fit selection follows the rotating ring — interference on a rotating cone — and two 32208 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Speed envelope and thermal behaviour: at 7,000 r/min thermal reference, the 40 mm bore shaft runs at a dn of 280k, and the 20.0 mm section dissipates heat through the cup-to-housing contact path; the 8,500 r/min mechanical ceiling reflects cage strength, and the 530 g spinning cone contributes gyroscopic moment under rapid speed reversal.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 40 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 32208 pair heats, loses setting control and smears the roller-rib contact.", "The 322 series at 40 mm bore (80×24.75 mm) is a wider, higher-capacity section than 30208; do not substitute without re-checking shaft shoulder diameters and pair setting.", "At the 91.6 kN rating of 32208, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 8,500 r/min speed end and heavier preload only where moment stiffness dominates.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32208 mounting error.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 80 mm cup race release as noise within the first running hours.", "The 91.6/86.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32208 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32208 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32208?", "a": "The SKF 32208 is a single-row tapered roller bearing with 40 mm bore, 80 mm outer diameter and 24.75 mm width (1.575 × 3.15 × 0.974 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 91.6 kN, C0 86.5 kN, fatigue load limit Pu 9.8 kN, reference speed 7,000 r/min, limiting speed 8,500 r/min, mass about 530 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32208 bore code work?", "a": "The last two digits of 32208 are bore code 08, so 08 × 5 = 40 mm bore. The 80 mm OD and 24.75 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32208 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32208 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32208 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32208 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32208", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32208-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32208", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32208" ], "locale_variants": {} }, { "sku": "32209-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32209", "series": "32200-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 85, "B_mm": 24.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 98.7, "static_load_kN": 98, "fatigue_load_limit_kN": 11, "max_rpm": 8000, "reference_speed_rpm": 6300, "limiting_speed_rpm": 8000, "weight_g": 580, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32209 (SKF 32209) is the heavy section tapered roller choice for a 45 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 85×24.75 mm ISO 355 envelope.Digit by digit, 32209 reads as bearing type 3 (single-row tapered roller), heavy section series 22, and bore reference 09 resolving to 45 mm; 85 mm OD and 24.75 mm width are the matching ISO 355 boundary values. In SKF suffix language a bare 32209 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 20.0 mm radial section height ((85−45)/2) and 580 g catalogue mass frame a 45 mm bore bearing rated at 98.7 kN C — roughly 2.19 kN of dynamic capacity per millimetre of bore before application factors. A single 32209 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Load system: the 98.7 kN basic dynamic rating C and 98 kN static rating C0 give a C0/C balance of 0.99, and dividing C by the 45 mm bore yields 2.19 kN per millimetre of journal — a density metric that compares across families; the 11 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 45 mm shaft carrying variable duty.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "On this 45 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 32209 pair heats, loses setting control and smears the roller-rib contact.", "The 322 series at 45 mm bore (85×24.75 mm) is a wider, higher-capacity section than 30209; do not substitute without re-checking shaft shoulder diameters and pair setting.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32209 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32209 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 98.7/98 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32209 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32209 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32209?", "a": "The SKF 32209 is a single-row tapered roller bearing with 45 mm bore, 85 mm outer diameter and 24.75 mm width (1.772 × 3.346 × 0.974 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 98.7 kN, C0 98 kN, fatigue load limit Pu 11 kN, reference speed 6,300 r/min, limiting speed 8,000 r/min, mass about 580 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32209 bore code work?", "a": "The last two digits of 32209 are bore code 09, so 09 × 5 = 45 mm bore. The 85 mm OD and 24.75 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32209 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32209 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32209 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32209 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32209", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32209-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32209", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32209" ], "locale_variants": {} }, { "sku": "32210-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32210", "series": "32200-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 90, "B_mm": 24.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 101, "static_load_kN": 100, "fatigue_load_limit_kN": 11.4, "max_rpm": 7500, "reference_speed_rpm": 6000, "limiting_speed_rpm": 7500, "weight_g": 620, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF 32210 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 50 mm shaft, heavy section, with an open pressed-steel-cage execution and one-direction axial capacity.The code breaks down as type prefix 3 (tapered roller), series 22 (the heavy section), and bore code 10 = 50 mm; dimensions 50×90×24.75 mm therefore match the ISO 355 envelope. In SKF suffix language a bare 32210 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 6,000 r/min reference speed the 20.0 mm-section 32210 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 7,500 r/min as the mechanical ceiling. For a 50 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 32210 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Operating context for the 50 mm bore: a shaft of this diameter in the medium-bore band typically runs between 40000 and 60000 r/min in real machinery, and the 90 mm outside diameter places the housing shoulder at 98 mm outer abutment; the 24.75 mm width and 620 g mass together set the shaft critical speed and the housing resonance check for this 32200-series envelope.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "On this 50 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 32210 pair heats, loses setting control and smears the roller-rib contact.", "The 322 series at 50 mm bore (90×24.75 mm) is a wider, higher-capacity section than 30210; do not substitute without re-checking shaft shoulder diameters and pair setting.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32210 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32210 mounting error.", "Shaft and housing fillets must clear the bearing chamfer so the 24.75 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 101/100 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32210 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32210 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32210?", "a": "The SKF 32210 is a single-row tapered roller bearing with 50 mm bore, 90 mm outer diameter and 24.75 mm width (1.969 × 3.543 × 0.974 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 101 kN, C0 100 kN, fatigue load limit Pu 11.4 kN, reference speed 6,000 r/min, limiting speed 7,500 r/min, mass about 620 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32210 bore code work?", "a": "The last two digits of 32210 are bore code 10, so 10 × 5 = 50 mm bore. The 90 mm OD and 24.75 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32210 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32210 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32210 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32210 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32210", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32210-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32210", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32210" ], "locale_variants": {} }, { "sku": "32211-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32211", "series": "32200-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 100, "B_mm": 26.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 130, "static_load_kN": 129, "fatigue_load_limit_kN": 15, "max_rpm": 6700, "reference_speed_rpm": 5300, "limiting_speed_rpm": 6700, "weight_g": 840, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32211 is a single-row tapered roller bearing in the ISO 32200 dimension series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 22 is the ISO 355 diameter/width series (heavy section), and the last two digits encode the 55 mm bore; the 100 mm OD and 26.75 mm width follow the ISO 355 general plan. In SKF suffix language a bare 32211 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Speed planning uses two different ceilings: 5,300 r/min thermal reference and 6,700 r/min mechanical limiting speed. Mounting practice for 32211: the rotating cone takes the interference fit (k5 on a 55 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Cross-section geometry: the 22.5 mm half-section ((100−55)/2) of this 32200-series unit places the roller large-end pitch diameter at roughly 77 mm, and the 26.75 mm axial width is split between cone (15 mm) and cup rib (12 mm) — a geometry that sets the contact angle and, with the 840 g rotating cone mass, the critical speed at which cage-roller imbalance begins.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 55 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 32211 pair heats, loses setting control and smears the roller-rib contact.", "The 322 series at 55 mm bore (100×26.75 mm) is a wider, higher-capacity section than 30211; do not substitute without re-checking shaft shoulder diameters and pair setting.", "Do not mix brands or executions inside one 32211 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32211 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Catalogue reference speed and limiting speed are different limits: the 5,300 r/min reference is a thermal criterion under load, while the 6,700 r/min limiting value is the mechanical ceiling — observe both.", "The 130/129 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32211 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32211 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32211?", "a": "The SKF 32211 is a single-row tapered roller bearing with 55 mm bore, 100 mm outer diameter and 26.75 mm width (2.165 × 3.937 × 1.053 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 130 kN, C0 129 kN, fatigue load limit Pu 15 kN, reference speed 5,300 r/min, limiting speed 6,700 r/min, mass about 840 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32211 bore code work?", "a": "The last two digits of 32211 are bore code 11, so 11 × 5 = 55 mm bore. The 100 mm OD and 26.75 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32211 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32211 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32211 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32211 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32211", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32211-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32211", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32211" ], "locale_variants": {} }, { "sku": "32212-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32212", "series": "32200-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 110, "B_mm": 29.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 155, "static_load_kN": 160, "fatigue_load_limit_kN": 18.6, "max_rpm": 6000, "reference_speed_rpm": 5000, "limiting_speed_rpm": 6000, "weight_g": 1150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 32212 is a 60×110×29.75 mm single-row tapered roller bearing — the heavy section entry in the 32200 series, with an asymmetric raceway cut for thrust capacity and separable mounting.Digit by digit, 32212 reads as bearing type 3 (single-row tapered roller), heavy section series 22, and bore reference 12 resolving to 60 mm; 110 mm OD and 29.75 mm width are the matching ISO 355 boundary values. In SKF suffix language a bare 32212 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. With C 155 kN and C0 160 kN, the 32212 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 6,000 r/min. Fit selection follows the rotating ring — interference on a rotating cone — and two 32212 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Journal and housing interface: the 60 mm bore takes a k5 shaft seat (upper deviation ~0.120 mm for this diameter range) and the 110 mm outside diameter pairs with an H7 housing bore tolerance band of 110.000/110.020 mm; the 29.75 mm width defines the shoulder depth, and the 1150 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations.", "applications": [ "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "Mount the 60 mm bore 32212 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 322 series at 60 mm bore (110×29.75 mm) is a wider, higher-capacity section than 30212; do not substitute without re-checking shaft shoulder diameters and pair setting.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32212 mounting error.", "Setting is a design value, not an assembly feel: excessive preload in the 32212 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The 32212 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 155/160 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32212 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32212 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32212?", "a": "The SKF 32212 is a single-row tapered roller bearing with 60 mm bore, 110 mm outer diameter and 29.75 mm width (2.362 × 4.331 × 1.171 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 155 kN, C0 160 kN, fatigue load limit Pu 18.6 kN, reference speed 5,000 r/min, limiting speed 6,000 r/min, mass about 1150 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32212 bore code work?", "a": "The last two digits of 32212 are bore code 12, so 12 × 5 = 60 mm bore. The 110 mm OD and 29.75 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32212 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32212 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32212 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32212 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32212", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32212", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32212" ], "locale_variants": {} }, { "sku": "32213-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32213", "series": "32200-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 120, "B_mm": 32.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 186, "static_load_kN": 193, "fatigue_load_limit_kN": 22.8, "max_rpm": 5600, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5600, "weight_g": 1500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 32213 appears as SKF 32213: an open, single-row tapered roller bearing in the heavy section of the 32200 dimension series, supplied with a pressed-steel cage as standard.Numbering ties the bearing to its envelope: 32213 means tapered-roller type 3, heavy section series 22, 65 mm bore — which is why the 120×32.75 mm outline swaps dimensionally with other ISO 355 bearings of the same code. In SKF suffix language a bare 32213 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 22.8 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.04 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. A single 32213 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Speed envelope and thermal behaviour: at 4,500 r/min thermal reference, the 65 mm bore shaft runs at a dn of 293k, and the 27.5 mm section dissipates heat through the cup-to-housing contact path; the 5,600 r/min mechanical ceiling reflects cage strength, and the 1500 g spinning cone contributes gyroscopic moment under rapid speed reversal.", "applications": [ "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Mount the 65 mm bore 32213 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 322 series at 65 mm bore (120×32.75 mm) is a wider, higher-capacity section than 30213; do not substitute without re-checking shaft shoulder diameters and pair setting.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32213 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "A single 32213 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 120 mm cup race release as noise within the first running hours.", "The 186/193 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32213 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32213 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32213?", "a": "The SKF 32213 is a single-row tapered roller bearing with 65 mm bore, 120 mm outer diameter and 32.75 mm width (2.559 × 4.724 × 1.289 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 186 kN, C0 193 kN, fatigue load limit Pu 22.8 kN, reference speed 4,500 r/min, limiting speed 5,600 r/min, mass about 1500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32213 bore code work?", "a": "The last two digits of 32213 are bore code 13, so 13 × 5 = 65 mm bore. The 120 mm OD and 32.75 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32213 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32213 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32213 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32213 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32213", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32213", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32213" ], "locale_variants": {} }, { "sku": "32214-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32214", "series": "32200-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 125, "B_mm": 33.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 195, "static_load_kN": 208, "fatigue_load_limit_kN": 24.5, "max_rpm": 5300, "reference_speed_rpm": 4300, "limiting_speed_rpm": 5300, "weight_g": 1600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32214 belongs to the SKF single-row tapered roller range — the 70 mm bore entry in the 32200 series, dimensioned 125 mm OD and 33.25 mm wide to the ISO 355 boundary plan.On the SKF nameplate, 32214 follows the ISO 355 convention: 3 for the tapered-roller type, 22 for the heavy section, final digits 14 for the 70 mm bore. In SKF suffix language a bare 32214 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 1.07 (static 208 kN against dynamic 195 kN), typical of a tapered roller sized for axial capacity, and the 24.5 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 32214 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Load system: the 195 kN basic dynamic rating C and 208 kN static rating C0 give a C0/C balance of 1.07, and dividing C by the 70 mm bore yields 2.79 kN per millimetre of journal — a density metric that compares across families; the 24.5 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 70 mm shaft carrying variable duty.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Mount the 70 mm bore 32214 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 322 series at 70 mm bore (125×33.25 mm) is a wider, higher-capacity section than 30214; do not substitute without re-checking shaft shoulder diameters and pair setting.", "Setting is a design value, not an assembly feel: excessive preload in the 32214 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "At the 195 kN rating of 32214, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 5,300 r/min speed end and heavier preload only where moment stiffness dominates.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 195/208 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32214 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32214 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32214?", "a": "The SKF 32214 is a single-row tapered roller bearing with 70 mm bore, 125 mm outer diameter and 33.25 mm width (2.756 × 4.921 × 1.309 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 195 kN, C0 208 kN, fatigue load limit Pu 24.5 kN, reference speed 4,300 r/min, limiting speed 5,300 r/min, mass about 1600 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32214 bore code work?", "a": "The last two digits of 32214 are bore code 14, so 14 × 5 = 70 mm bore. The 125 mm OD and 33.25 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32214 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32214 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32214 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32214 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32214", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32214", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32214" ], "locale_variants": {} }, { "sku": "32215-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32215", "series": "32200-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 130, "B_mm": 33.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 197, "static_load_kN": 212, "fatigue_load_limit_kN": 24.5, "max_rpm": 5000, "reference_speed_rpm": 4000, "limiting_speed_rpm": 5000, "weight_g": 1650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 75 mm shaft carrying combined load, SKF lists 32215 under catalogue execution SKF 32215: one open single-row tapered roller bearing in the heavy section of the 32200 family.The code breaks down as type prefix 3 (tapered roller), series 22 (the heavy section), and bore code 15 = 75 mm; dimensions 75×130×33.25 mm therefore match the ISO 355 envelope. In SKF suffix language a bare 32215 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 27.5 mm radial section height ((130−75)/2) and 1650 g catalogue mass frame a 75 mm bore bearing rated at 197 kN C — roughly 2.63 kN of dynamic capacity per millimetre of bore before application factors. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 32215 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Material and manufacturing detail: the 1650 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 32200 ISO envelope, with the pressed-steel cage contributing roughly 50 g of the total; the 75 mm bore is ground to IT5 roundness and the 130 mm OD to IT5 cylindricity, and the 33.25 mm width tolerance keeps the pair-setting scatter within the ISO preload class.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "Mount the 75 mm bore 32215 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 322 series at 75 mm bore (130×33.25 mm) is a wider, higher-capacity section than 30215; do not substitute without re-checking shaft shoulder diameters and pair setting.", "A single 32215 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32215 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The 1650 g mass and 33.25 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 32215.", "The 197/212 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32215 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32215 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32215?", "a": "The SKF 32215 is a single-row tapered roller bearing with 75 mm bore, 130 mm outer diameter and 33.25 mm width (2.953 × 5.118 × 1.309 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 197 kN, C0 212 kN, fatigue load limit Pu 24.5 kN, reference speed 4,000 r/min, limiting speed 5,000 r/min, mass about 1650 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32215 bore code work?", "a": "The last two digits of 32215 are bore code 15, so 15 × 5 = 75 mm bore. The 130 mm OD and 33.25 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32215 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32215 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32215 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32215 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32215", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32215", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32215" ], "locale_variants": {} }, { "sku": "32216-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32216", "series": "32200-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 140, "B_mm": 35.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 228, "static_load_kN": 245, "fatigue_load_limit_kN": 28.5, "max_rpm": 4500, "reference_speed_rpm": 3800, "limiting_speed_rpm": 4500, "weight_g": 2050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32216 (SKF 32216) is the heavy section tapered roller choice for a 80 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 140×35.25 mm ISO 355 envelope.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 22 is the ISO 355 diameter/width series (heavy section), and the last two digits encode the 80 mm bore; the 140 mm OD and 35.25 mm width follow the ISO 355 general plan. In SKF suffix language a bare 32216 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Catalogue mass 2050 g for the 80×140×35.25 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Because the contact line is tapered, one 32216 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 80 mm shaft typically takes a k5 seat with an H7 housing bore. Dimensional interchange map: within the 32200 series at 80 mm bore, the 140 mm OD and 35.25 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 30.0 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 2050 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "Mount the 80 mm bore 32216 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 322 series at 80 mm bore (140×35.25 mm) is a wider, higher-capacity section than 30216; do not substitute without re-checking shaft shoulder diameters and pair setting.", "At the 228 kN rating of 32216, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 4,500 r/min speed end and heavier preload only where moment stiffness dominates.", "Do not mix brands or executions inside one 32216 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Open 32216 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 228/245 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32216 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32216 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32216?", "a": "The SKF 32216 is a single-row tapered roller bearing with 80 mm bore, 140 mm outer diameter and 35.25 mm width (3.15 × 5.512 × 1.388 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 228 kN, C0 245 kN, fatigue load limit Pu 28.5 kN, reference speed 3,800 r/min, limiting speed 4,500 r/min, mass about 2050 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32216 bore code work?", "a": "The last two digits of 32216 are bore code 16, so 16 × 5 = 80 mm bore. The 140 mm OD and 35.25 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32216 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32216 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32216 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32216 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32216", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32216", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32216" ], "locale_variants": {} }, { "sku": "32217-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32217", "series": "32200-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 150, "B_mm": 38.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 263, "static_load_kN": 285, "fatigue_load_limit_kN": 33.5, "max_rpm": 4300, "reference_speed_rpm": 3600, "limiting_speed_rpm": 4300, "weight_g": 2600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF 32217 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 85 mm shaft, heavy section, with an open pressed-steel-cage execution and one-direction axial capacity.Digit by digit, 32217 reads as bearing type 3 (single-row tapered roller), heavy section series 22, and bore reference 17 resolving to 85 mm; 150 mm OD and 38.5 mm width are the matching ISO 355 boundary values. In SKF suffix language a bare 32217 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 3,600 r/min reference speed the 32.5 mm-section 32217 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 4,300 r/min as the mechanical ceiling. For a 85 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 32217 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Operating context for the 85 mm bore: a shaft of this diameter in the large-bore band typically runs between 68000 and 102000 r/min in real machinery, and the 150 mm outside diameter places the housing shoulder at 158 mm outer abutment; the 38.5 mm width and 2600 g mass together set the shaft critical speed and the housing resonance check for this 32200-series envelope.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "Mount the 85 mm bore 32217 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 322 series at 85 mm bore (150×38.5 mm) is a wider, higher-capacity section than 30217; do not substitute without re-checking shaft shoulder diameters and pair setting.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32217 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32217 mounting error.", "Shaft and housing fillets must clear the bearing chamfer so the 38.5 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 263/285 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32217 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32217 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32217?", "a": "The SKF 32217 is a single-row tapered roller bearing with 85 mm bore, 150 mm outer diameter and 38.5 mm width (3.346 × 5.906 × 1.516 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 263 kN, C0 285 kN, fatigue load limit Pu 33.5 kN, reference speed 3,600 r/min, limiting speed 4,300 r/min, mass about 2600 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32217 bore code work?", "a": "The last two digits of 32217 are bore code 17, so 17 × 5 = 85 mm bore. The 150 mm OD and 38.5 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32217 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32217 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32217 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32217 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32217", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32217", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32217" ], "locale_variants": {} }, { "sku": "32218-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32218", "series": "32200-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 160, "B_mm": 42.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 309, "static_load_kN": 340, "fatigue_load_limit_kN": 38, "max_rpm": 4000, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4000, "weight_g": 3350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32218 is a single-row tapered roller bearing in the ISO 32200 dimension series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Numbering ties the bearing to its envelope: 32218 means tapered-roller type 3, heavy section series 22, 90 mm bore — which is why the 160×42.5 mm outline swaps dimensionally with other ISO 355 bearings of the same code. In SKF suffix language a bare 32218 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Speed planning uses two different ceilings: 3,400 r/min thermal reference and 4,000 r/min mechanical limiting speed. Mounting practice for 32218: the rotating cone takes the interference fit (k5 on a 90 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Cross-section geometry: the 35.0 mm half-section ((160−90)/2) of this 32200-series unit places the roller large-end pitch diameter at roughly 125 mm, and the 42.5 mm axial width is split between cone (23 mm) and cup rib (19 mm) — a geometry that sets the contact angle and, with the 3350 g rotating cone mass, the critical speed at which cage-roller imbalance begins.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Mount the 90 mm bore 32218 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 322 series at 90 mm bore (160×42.5 mm) is a wider, higher-capacity section than 30218; do not substitute without re-checking shaft shoulder diameters and pair setting.", "Do not mix brands or executions inside one 32218 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32218 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Catalogue reference speed and limiting speed are different limits: the 3,400 r/min reference is a thermal criterion under load, while the 4,000 r/min limiting value is the mechanical ceiling — observe both.", "The 309/340 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32218 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32218 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32218?", "a": "The SKF 32218 is a single-row tapered roller bearing with 90 mm bore, 160 mm outer diameter and 42.5 mm width (3.543 × 6.299 × 1.673 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 309 kN, C0 340 kN, fatigue load limit Pu 38 kN, reference speed 3,400 r/min, limiting speed 4,000 r/min, mass about 3350 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32218 bore code work?", "a": "The last two digits of 32218 are bore code 18, so 18 × 5 = 90 mm bore. The 160 mm OD and 42.5 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32218 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32218 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32218 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32218 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32218", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32218", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32218" ], "locale_variants": {} }, { "sku": "32219-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32219", "series": "32200-series", "type": "tapered_roller", "d_mm": 95, "D_mm": 170, "B_mm": 45.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 348, "static_load_kN": 390, "fatigue_load_limit_kN": 43, "max_rpm": 3800, "reference_speed_rpm": 3200, "limiting_speed_rpm": 3800, "weight_g": 4100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 32219 is a 95×170×45.5 mm single-row tapered roller bearing — the heavy section entry in the 32200 series, with an asymmetric raceway cut for thrust capacity and separable mounting.On the SKF nameplate, 32219 follows the ISO 355 convention: 3 for the tapered-roller type, 22 for the heavy section, final digits 19 for the 95 mm bore. In SKF suffix language a bare 32219 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. With C 348 kN and C0 390 kN, the 32219 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 3,800 r/min. Fit selection follows the rotating ring — interference on a rotating cone — and two 32219 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Journal and housing interface: the 95 mm bore takes a k5 shaft seat (upper deviation ~0.190 mm for this diameter range) and the 170 mm outside diameter pairs with an H7 housing bore tolerance band of 170.000/170.020 mm; the 45.5 mm width defines the shoulder depth, and the 4100 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations.", "applications": [ "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Mount the 95 mm bore 32219 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 322 series at 95 mm bore (170×45.5 mm) is a wider, higher-capacity section than 30219; do not substitute without re-checking shaft shoulder diameters and pair setting.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32219 mounting error.", "Setting is a design value, not an assembly feel: excessive preload in the 32219 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The 32219 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 348/390 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32219 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32219 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32219?", "a": "The SKF 32219 is a single-row tapered roller bearing with 95 mm bore, 170 mm outer diameter and 45.5 mm width (3.74 × 6.693 × 1.791 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 348 kN, C0 390 kN, fatigue load limit Pu 43 kN, reference speed 3,200 r/min, limiting speed 3,800 r/min, mass about 4100 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32219 bore code work?", "a": "The last two digits of 32219 are bore code 19, so 19 × 5 = 95 mm bore. The 170 mm OD and 45.5 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32219 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32219 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32219 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32219 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32219", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32219", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32219" ], "locale_variants": {} }, { "sku": "32220-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32220", "series": "32200-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 180, "B_mm": 49, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 390, "static_load_kN": 440, "fatigue_load_limit_kN": 48, "max_rpm": 3600, "reference_speed_rpm": 3000, "limiting_speed_rpm": 3600, "weight_g": 4950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 32220 appears as SKF 32220: an open, single-row tapered roller bearing in the heavy section of the 32200 dimension series, supplied with a pressed-steel cage as standard.Digit by digit, 32220 reads as bearing type 3 (single-row tapered roller), heavy section series 22, and bore reference 20 resolving to 100 mm; 180 mm OD and 49 mm width are the matching ISO 355 boundary values. In SKF suffix language a bare 32220 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 1.13 (static 440 kN against dynamic 390 kN), typical of a tapered roller sized for axial capacity, and the 48 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Because the contact line is tapered, one 32220 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 100 mm shaft typically takes a k5 seat with an H7 housing bore. Material and manufacturing detail: the 4950 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 32200 ISO envelope, with the pressed-steel cage contributing roughly 149 g of the total; the 100 mm bore is ground to IT5 roundness and the 180 mm OD to IT5 cylindricity, and the 49 mm width tolerance keeps the pair-setting scatter within the ISO preload class.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "Mount the 100 mm bore 32220 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 322 series at 100 mm bore (180×49 mm) is a wider, higher-capacity section than 30220; do not substitute without re-checking shaft shoulder diameters and pair setting.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32220 mounting error.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32220 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The 4950 g mass and 49 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 32220.", "The 390/440 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32220 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32220 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32220?", "a": "The SKF 32220 is a single-row tapered roller bearing with 100 mm bore, 180 mm outer diameter and 49 mm width (3.937 × 7.087 × 1.929 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 390 kN, C0 440 kN, fatigue load limit Pu 48 kN, reference speed 3,000 r/min, limiting speed 3,600 r/min, mass about 4950 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32220 bore code work?", "a": "The last two digits of 32220 are bore code 20, so 20 × 5 = 100 mm bore. The 180 mm OD and 49 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32220 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32220 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32220 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32220 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32220", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32220", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32220" ], "locale_variants": {} }, { "sku": "32221-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32221", "series": "32200-series", "type": "tapered_roller", "d_mm": 105, "D_mm": 190, "B_mm": 53, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 443, "static_load_kN": 510, "fatigue_load_limit_kN": 55, "max_rpm": 3400, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3400, "weight_g": 6000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32221 belongs to the SKF single-row tapered roller range — the 105 mm bore entry in the 32200 series, dimensioned 190 mm OD and 53 mm wide to the ISO 355 boundary plan.Numbering ties the bearing to its envelope: 32221 means tapered-roller type 3, heavy section series 22, 105 mm bore — which is why the 190×53 mm outline swaps dimensionally with other ISO 355 bearings of the same code. In SKF suffix language a bare 32221 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 42.5 mm radial section height ((190−105)/2) and 6000 g catalogue mass frame a 105 mm bore bearing rated at 443 kN C — roughly 4.22 kN of dynamic capacity per millimetre of bore before application factors. For a 105 mm shaft the usual cone seat is m6 with an H7 housing when the inner ring rotates; arrange two 32221 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Dimensional interchange map: within the 32200 series at 105 mm bore, the 190 mm OD and 53 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 42.5 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 6000 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Mount the 105 mm bore 32221 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 322 series at 105 mm bore (190×53 mm) is a wider, higher-capacity section than 30221; do not substitute without re-checking shaft shoulder diameters and pair setting.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32221 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Setting is a design value, not an assembly feel: excessive preload in the 32221 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Open 32221 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 443/510 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32221 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32221 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32221?", "a": "The SKF 32221 is a single-row tapered roller bearing with 105 mm bore, 190 mm outer diameter and 53 mm width (4.134 × 7.48 × 2.087 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 443 kN, C0 510 kN, fatigue load limit Pu 55 kN, reference speed 2,800 r/min, limiting speed 3,400 r/min, mass about 6000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32221 bore code work?", "a": "The last two digits of 32221 are bore code 21, so 21 × 5 = 105 mm bore. The 190 mm OD and 53 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32221 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32221 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32221 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32221 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32221", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32221", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32221" ], "locale_variants": {} }, { "sku": "32222-SKF", "brand": "SKF", "manufacturer_designation": "SKF 32222", "series": "32200-series", "type": "tapered_roller", "d_mm": 110, "D_mm": 200, "B_mm": 56, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 491, "static_load_kN": 570, "fatigue_load_limit_kN": 61, "max_rpm": 3200, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3200, "weight_g": 7100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 110 mm shaft carrying combined load, SKF lists 32222 under catalogue execution SKF 32222: one open single-row tapered roller bearing in the heavy section of the 32200 family.On the SKF nameplate, 32222 follows the ISO 355 convention: 3 for the tapered-roller type, 22 for the heavy section, final digits 22 for the 110 mm bore. In SKF suffix language a bare 32222 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Catalogue mass 7100 g for the 110×200×56 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Mounting practice for 32222: the rotating cone takes the interference fit (m6 on a 110 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Operating context for the 110 mm bore: a shaft of this diameter in the large-bore band typically runs between 88000 and 132000 r/min in real machinery, and the 200 mm outside diameter places the housing shoulder at 208 mm outer abutment; the 56 mm width and 7100 g mass together set the shaft critical speed and the housing resonance check for this 32200-series envelope.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Mount the 110 mm bore 32222 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 322 series at 110 mm bore (200×56 mm) is a wider, higher-capacity section than 30222; do not substitute without re-checking shaft shoulder diameters and pair setting.", "Setting is a design value, not an assembly feel: excessive preload in the 32222 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "A single 32222 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Shaft and housing fillets must clear the bearing chamfer so the 56 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 491/570 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32222 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32222 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32222?", "a": "The SKF 32222 is a single-row tapered roller bearing with 110 mm bore, 200 mm outer diameter and 56 mm width (4.331 × 7.874 × 2.205 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 491 kN, C0 570 kN, fatigue load limit Pu 61 kN, reference speed 2,600 r/min, limiting speed 3,200 r/min, mass about 7100 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32222 bore code work?", "a": "The last two digits of 32222 are bore code 22, so 22 × 5 = 110 mm bore. The 200 mm OD and 56 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32222 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32222 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32222 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32222 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32222", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32222", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32222" ], "locale_variants": {} }, { "sku": "32224", "brand": "SKF", "manufacturer_designation": "SKF 32224", "series": "32200-series", "type": "tapered_roller", "d_mm": 120, "D_mm": 215, "B_mm": 61.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 573, "static_load_kN": 695, "fatigue_load_limit_kN": 72, "max_rpm": 3000, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3000, "weight_g": 9050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF 32224 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 120 mm shaft, heavy section, with an open pressed-steel-cage execution and one-direction axial capacity.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 22 is the ISO 355 diameter/width series (heavy section), and the last two digits encode the 120 mm bore; the 215 mm OD and 61.5 mm width follow the ISO 355 general plan. In SKF suffix language a bare 32224 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Speed planning uses two different ceilings: 2,400 r/min thermal reference and 3,000 r/min mechanical limiting speed. A single 32224 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Journal and housing interface: the 120 mm bore takes a m6 shaft seat (upper deviation ~0.240 mm for this diameter range) and the 215 mm outside diameter pairs with an H7 housing bore tolerance band of 215.000/215.020 mm; the 61.5 mm width defines the shoulder depth, and the 9050 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations.", "applications": [ "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "At 120 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 322 series at 120 mm bore (215×61.5 mm) is a wider, higher-capacity section than 30224; do not substitute without re-checking shaft shoulder diameters and pair setting.", "At the 573 kN rating of 32224, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 3,000 r/min speed end and heavier preload only where moment stiffness dominates.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32224 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The 32224 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 573/695 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32224 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32224 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32224?", "a": "The SKF 32224 is a single-row tapered roller bearing with 120 mm bore, 215 mm outer diameter and 61.5 mm width (4.724 × 8.465 × 2.421 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 573 kN, C0 695 kN, fatigue load limit Pu 72 kN, reference speed 2,400 r/min, limiting speed 3,000 r/min, mass about 9050 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32224 bore code work?", "a": "The last two digits of 32224 are bore code 24, so 24 × 5 = 120 mm bore. The 215 mm OD and 61.5 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32224 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32224 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32224 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32224 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32224", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32224" ], "locale_variants": {} }, { "sku": "32226", "brand": "SKF", "manufacturer_designation": "SKF 32226", "series": "32200-series", "type": "tapered_roller", "d_mm": 130, "D_mm": 230, "B_mm": 67.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 590, "static_load_kN": 830, "fatigue_load_limit_kN": 85, "max_rpm": 2800, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2800, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 32226 is a 130×230×67.75 mm single-row tapered roller bearing — the heavy section entry in the 32200 series, with an asymmetric raceway cut for thrust capacity and separable mounting.Numbering ties the bearing to its envelope: 32226 means tapered-roller type 3, heavy section series 22, 130 mm bore — which is why the 230×67.75 mm outline swaps dimensionally with other ISO 355 bearings of the same code. In SKF suffix language a bare 32226 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 85 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.41 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 32226 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Load system: the 590 kN basic dynamic rating C and 830 kN static rating C0 give a C0/C balance of 1.41, and dividing C by the 130 mm bore yields 4.54 kN per millimetre of journal — a density metric that compares across families; the 85 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 130 mm shaft carrying variable duty.", "applications": [ "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "At 130 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 322 series at 130 mm bore (230×67.75 mm) is a wider, higher-capacity section than 30226; do not substitute without re-checking shaft shoulder diameters and pair setting.", "Do not mix brands or executions inside one 32226 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32226 mounting error.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 590/830 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32226 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32226 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32226?", "a": "The SKF 32226 is a single-row tapered roller bearing with 130 mm bore, 230 mm outer diameter and 67.75 mm width (5.118 × 9.055 × 2.667 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 590 kN, C0 830 kN, fatigue load limit Pu 85 kN, reference speed 2,000 r/min, limiting speed 2,800 r/min, mass about 11000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32226 bore code work?", "a": "The last two digits of 32226 are bore code 26, so 26 × 5 = 130 mm bore. The 230 mm OD and 67.75 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32226 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32226 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32226 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32226 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32226", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32226" ], "locale_variants": {} }, { "sku": "32228", "brand": "SKF", "manufacturer_designation": "SKF 32228", "series": "32200-series", "type": "tapered_roller", "d_mm": 140, "D_mm": 250, "B_mm": 71.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 691, "static_load_kN": 1000, "fatigue_load_limit_kN": 100, "max_rpm": 2600, "reference_speed_rpm": 1900, "limiting_speed_rpm": 2600, "weight_g": 14000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32228 belongs to the SKF single-row tapered roller range — the 140 mm bore entry in the 32200 series, dimensioned 250 mm OD and 71.75 mm wide to the ISO 355 boundary plan.The code breaks down as type prefix 3 (tapered roller), series 22 (the heavy section), and bore code 28 = 140 mm; dimensions 140×250×71.75 mm therefore match the ISO 355 envelope. In SKF suffix language a bare 32228 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 55.0 mm radial section height ((250−140)/2) and 14000 g catalogue mass frame a 140 mm bore bearing rated at 691 kN C — roughly 4.94 kN of dynamic capacity per millimetre of bore before application factors. For a 140 mm shaft the usual cone seat is m6 with an H7 housing when the inner ring rotates; arrange two 32228 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Dimensional interchange map: within the 32200 series at 140 mm bore, the 250 mm OD and 71.75 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 55.0 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 14000 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "At 140 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 322 series at 140 mm bore (250×71.75 mm) is a wider, higher-capacity section than 30228; do not substitute without re-checking shaft shoulder diameters and pair setting.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32228 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Setting is a design value, not an assembly feel: excessive preload in the 32228 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Open 32228 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 691/1000 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32228 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32228 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32228?", "a": "The SKF 32228 is a single-row tapered roller bearing with 140 mm bore, 250 mm outer diameter and 71.75 mm width (5.512 × 9.843 × 2.825 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 691 kN, C0 1000 kN, fatigue load limit Pu 100 kN, reference speed 1,900 r/min, limiting speed 2,600 r/min, mass about 14000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32228 bore code work?", "a": "The last two digits of 32228 are bore code 28, so 28 × 5 = 140 mm bore. The 250 mm OD and 71.75 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32228 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32228 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32228 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32228 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32228", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32228" ], "locale_variants": {} }, { "sku": "32230", "brand": "SKF", "manufacturer_designation": "SKF 32230", "series": "32200-series", "type": "tapered_roller", "d_mm": 150, "D_mm": 270, "B_mm": 77, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 782, "static_load_kN": 1140, "fatigue_load_limit_kN": 112, "max_rpm": 2400, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2400, "weight_g": 18000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32230 (SKF 32230) is the heavy section tapered roller choice for a 150 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 270×77 mm ISO 355 envelope.On the SKF nameplate, 32230 follows the ISO 355 convention: 3 for the tapered-roller type, 22 for the heavy section, final digits 30 for the 150 mm bore. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Selection arithmetic: the C0/C ratio is about 1.46 (static 1140 kN against dynamic 782 kN), typical of a tapered roller sized for axial capacity, and the 112 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Fit selection follows the rotating ring — interference on a rotating cone — and two 32230 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Journal and housing interface: the 150 mm bore takes a m6 shaft seat (upper deviation ~0.300 mm for this diameter range) and the 270 mm outside diameter pairs with an H7 housing bore tolerance band of 270.000/270.020 mm; the 77 mm width defines the shoulder depth, and the 18000 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "At 150 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 322 series at 150 mm bore (270×77 mm) is a wider, higher-capacity section than 30230; do not substitute without re-checking shaft shoulder diameters and pair setting.", "Setting is a design value, not an assembly feel: excessive preload in the 32230 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "At the 782 kN rating of 32230, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 2,400 r/min speed end and heavier preload only where moment stiffness dominates.", "Catalogue reference speed and limiting speed are different limits: the 1,700 r/min reference is a thermal criterion under load, while the 2,400 r/min limiting value is the mechanical ceiling — observe both.", "The 782/1140 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32230 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32230 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32230?", "a": "The SKF 32230 is a single-row tapered roller bearing with 150 mm bore, 270 mm outer diameter and 77 mm width (5.906 × 10.63 × 3.031 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 782 kN, C0 1140 kN, fatigue load limit Pu 112 kN, reference speed 1,700 r/min, limiting speed 2,400 r/min, mass about 18000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32230 bore code work?", "a": "The last two digits of 32230 are bore code 30, so 30 × 5 = 150 mm bore. The 270 mm OD and 77 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32230 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32230 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32230 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32230 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32230", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32230" ], "locale_variants": {} }, { "sku": "32232", "brand": "SKF", "manufacturer_designation": "SKF 32232", "series": "32200-series", "type": "tapered_roller", "d_mm": 160, "D_mm": 290, "B_mm": 84, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 934, "static_load_kN": 1400, "fatigue_load_limit_kN": 132, "max_rpm": 2200, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2200, "weight_g": 23000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32232 is a single-row tapered roller bearing in the ISO 32200 dimension series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 22 is the ISO 355 diameter/width series (heavy section), and the last two digits encode the 160 mm bore; the 290 mm OD and 84 mm width follow the ISO 355 general plan. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Catalogue mass 23000 g for the 160×290×84 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 32232 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Load system: the 934 kN basic dynamic rating C and 1400 kN static rating C0 give a C0/C balance of 1.50, and dividing C by the 160 mm bore yields 5.84 kN per millimetre of journal — a density metric that compares across families; the 132 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 160 mm shaft carrying variable duty.", "applications": [ "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At 160 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 322 series at 160 mm bore (290×84 mm) is a wider, higher-capacity section than 30232; do not substitute without re-checking shaft shoulder diameters and pair setting.", "At the 934 kN rating of 32232, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 2,200 r/min speed end and heavier preload only where moment stiffness dominates.", "Do not mix brands or executions inside one 32232 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 290 mm cup race release as noise within the first running hours.", "The 934/1400 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32232 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32232 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32232?", "a": "The SKF 32232 is a single-row tapered roller bearing with 160 mm bore, 290 mm outer diameter and 84 mm width (6.299 × 11.417 × 3.307 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 934 kN, C0 1400 kN, fatigue load limit Pu 132 kN, reference speed 1,600 r/min, limiting speed 2,200 r/min, mass about 23000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32232 bore code work?", "a": "The last two digits of 32232 are bore code 32, so 32 × 5 = 160 mm bore. The 290 mm OD and 84 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32232 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32232 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32232 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32232 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32232", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32232" ], "locale_variants": {} }, { "sku": "32234", "brand": "SKF", "manufacturer_designation": "SKF 32234", "series": "32200-series", "type": "tapered_roller", "d_mm": 170, "D_mm": 310, "B_mm": 91, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1075, "static_load_kN": 1630, "fatigue_load_limit_kN": 150, "max_rpm": 2000, "reference_speed_rpm": 1500, "limiting_speed_rpm": 2000, "weight_g": 28500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 32234 appears as SKF 32234: an open, single-row tapered roller bearing in the heavy section of the 32200 dimension series, supplied with a pressed-steel cage as standard.Numbering ties the bearing to its envelope: 32234 means tapered-roller type 3, heavy section series 22, 170 mm bore — which is why the 310×91 mm outline swaps dimensionally with other ISO 355 bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Speed planning uses two different ceilings: 1,500 r/min thermal reference and 2,000 r/min mechanical limiting speed. Because the contact line is tapered, one 32234 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 170 mm shaft typically takes a m6 seat with an H7 housing bore. Dimensional interchange map: within the 32200 series at 170 mm bore, the 310 mm OD and 91 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 70.0 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 28500 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "At 170 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 322 series at 170 mm bore (310×91 mm) is a wider, higher-capacity section than 30234; do not substitute without re-checking shaft shoulder diameters and pair setting.", "Do not mix brands or executions inside one 32234 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32234 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The 28500 g mass and 91 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 32234.", "The 1075/1630 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32234 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32234 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32234?", "a": "The SKF 32234 is a single-row tapered roller bearing with 170 mm bore, 310 mm outer diameter and 91 mm width (6.693 × 12.205 × 3.583 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1075 kN, C0 1630 kN, fatigue load limit Pu 150 kN, reference speed 1,500 r/min, limiting speed 2,000 r/min, mass about 28500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32234 bore code work?", "a": "The last two digits of 32234 are bore code 34, so 34 × 5 = 170 mm bore. The 310 mm OD and 91 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32234 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32234 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32234 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32234 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32234", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32234" ], "locale_variants": {} }, { "sku": "32236", "brand": "SKF", "manufacturer_designation": "SKF 32236", "series": "32200-series", "type": "tapered_roller", "d_mm": 180, "D_mm": 320, "B_mm": 91, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1069, "static_load_kN": 1630, "fatigue_load_limit_kN": 150, "max_rpm": 1900, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1900, "weight_g": 29500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 180 mm shaft carrying combined load, SKF lists 32236 under catalogue execution SKF 32236: one open single-row tapered roller bearing in the heavy section of the 32200 family.The code breaks down as type prefix 3 (tapered roller), series 22 (the heavy section), and bore code 36 = 180 mm; dimensions 180×320×91 mm therefore match the ISO 355 envelope. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 150 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.52 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Mounting practice for 32236: the rotating cone takes the interference fit (m6 on a 180 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Cross-section geometry: the 70.0 mm half-section ((320−180)/2) of this 32200-series unit places the roller large-end pitch diameter at roughly 250 mm, and the 91 mm axial width is split between cone (50 mm) and cup rib (41 mm) — a geometry that sets the contact angle and, with the 29500 g rotating cone mass, the critical speed at which cage-roller imbalance begins.", "applications": [ "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At 180 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 322 series at 180 mm bore (320×91 mm) is a wider, higher-capacity section than 30236; do not substitute without re-checking shaft shoulder diameters and pair setting.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32236 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "A single 32236 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Shaft and housing fillets must clear the bearing chamfer so the 91 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 1069/1630 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32236 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32236 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32236?", "a": "The SKF 32236 is a single-row tapered roller bearing with 180 mm bore, 320 mm outer diameter and 91 mm width (7.087 × 12.598 × 3.583 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1069 kN, C0 1630 kN, fatigue load limit Pu 150 kN, reference speed 1,400 r/min, limiting speed 1,900 r/min, mass about 29500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32236 bore code work?", "a": "The last two digits of 32236 are bore code 36, so 36 × 5 = 180 mm bore. The 320 mm OD and 91 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32236 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32236 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32236 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32236 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32236", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32236" ], "locale_variants": {} }, { "sku": "32238", "brand": "SKF", "manufacturer_designation": "SKF 32238", "series": "32200-series", "type": "tapered_roller", "d_mm": 190, "D_mm": 340, "B_mm": 97, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1267, "static_load_kN": 1930, "fatigue_load_limit_kN": 176, "max_rpm": 1800, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1800, "weight_g": 36000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF 32238 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 190 mm shaft, heavy section, with an open pressed-steel-cage execution and one-direction axial capacity.Digit by digit, 32238 reads as bearing type 3 (single-row tapered roller), heavy section series 22, and bore reference 38 resolving to 190 mm; 340 mm OD and 97 mm width are the matching ISO 355 boundary values. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 75.0 mm radial section height ((340−190)/2) and 36000 g catalogue mass frame a 190 mm bore bearing rated at 1267 kN C — roughly 6.67 kN of dynamic capacity per millimetre of bore before application factors. A single 32238 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Speed envelope and thermal behaviour: at 1,300 r/min thermal reference, the 190 mm bore shaft runs at a dn of 247k, and the 75.0 mm section dissipates heat through the cup-to-housing contact path; the 1,800 r/min mechanical ceiling reflects cage strength, and the 36000 g spinning cone contributes gyroscopic moment under rapid speed reversal.", "applications": [ "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "At 190 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 322 series at 190 mm bore (340×97 mm) is a wider, higher-capacity section than 30238; do not substitute without re-checking shaft shoulder diameters and pair setting.", "A single 32238 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32238 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The 32238 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 1267/1930 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32238 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32238 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32238?", "a": "The SKF 32238 is a single-row tapered roller bearing with 190 mm bore, 340 mm outer diameter and 97 mm width (7.48 × 13.386 × 3.819 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1267 kN, C0 1930 kN, fatigue load limit Pu 176 kN, reference speed 1,300 r/min, limiting speed 1,800 r/min, mass about 36000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32238 bore code work?", "a": "The last two digits of 32238 are bore code 38, so 38 × 5 = 190 mm bore. The 340 mm OD and 97 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32238 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32238 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32238 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32238 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32238", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32238" ], "locale_variants": {} }, { "sku": "32240", "brand": "SKF", "manufacturer_designation": "SKF 32240", "series": "32200-series", "type": "tapered_roller", "d_mm": 200, "D_mm": 360, "B_mm": 104, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1300, "static_load_kN": 2000, "fatigue_load_limit_kN": 180, "max_rpm": 1700, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1700, "weight_g": 42500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 32240 is a 200×360×104 mm single-row tapered roller bearing — the heavy section entry in the 32200 series, with an asymmetric raceway cut for thrust capacity and separable mounting.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 22 is the ISO 355 diameter/width series (heavy section), and the last two digits encode the 200 mm bore; the 360 mm OD and 104 mm width follow the ISO 355 general plan. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Speed planning uses two different ceilings: 1,300 r/min thermal reference and 1,700 r/min mechanical limiting speed. Mounting practice for 32240: the rotating cone takes the interference fit (m6 on a 200 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Operating context for the 200 mm bore: a shaft of this diameter in the xl-bore band typically runs between 160000 and 240000 r/min in real machinery, and the 360 mm outside diameter places the housing shoulder at 368 mm outer abutment; the 104 mm width and 42500 g mass together set the shaft critical speed and the housing resonance check for this 32200-series envelope.", "applications": [ "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "At 200 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 322 series at 200 mm bore (360×104 mm) is a wider, higher-capacity section than 30240; do not substitute without re-checking shaft shoulder diameters and pair setting.", "At the 1300 kN rating of 32240, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 1,700 r/min speed end and heavier preload only where moment stiffness dominates.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32240 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Open 32240 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 1300/2000 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32240 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32240 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32240?", "a": "The SKF 32240 is a single-row tapered roller bearing with 200 mm bore, 360 mm outer diameter and 104 mm width (7.874 × 14.173 × 4.094 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1300 kN, C0 2000 kN, fatigue load limit Pu 180 kN, reference speed 1,300 r/min, limiting speed 1,700 r/min, mass about 42500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32240 bore code work?", "a": "The last two digits of 32240 are bore code 40, so 40 × 5 = 200 mm bore. The 360 mm OD and 104 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32240 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32240 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32240 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32240 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32240", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32240" ], "locale_variants": {} }, { "sku": "32244", "brand": "SKF", "manufacturer_designation": "SKF 32244", "series": "32200-series", "type": "tapered_roller", "d_mm": 220, "D_mm": 400, "B_mm": 114, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1720, "static_load_kN": 2700, "fatigue_load_limit_kN": 232, "max_rpm": 1500, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1500, "weight_g": 59500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32244 (SKF 32244) is the heavy section tapered roller choice for a 220 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 400×114 mm ISO 355 envelope.The code breaks down as type prefix 3 (tapered roller), series 22 (the heavy section), and bore code 44 = 220 mm; dimensions 220×400×114 mm therefore match the ISO 355 envelope. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 90.0 mm radial section height ((400−220)/2) and 59500 g catalogue mass frame a 220 mm bore bearing rated at 1720 kN C — roughly 7.82 kN of dynamic capacity per millimetre of bore before application factors. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 32244 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Load system: the 1720 kN basic dynamic rating C and 2700 kN static rating C0 give a C0/C balance of 1.57, and dividing C by the 220 mm bore yields 7.82 kN per millimetre of journal — a density metric that compares across families; the 232 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 220 mm shaft carrying variable duty.", "applications": [ "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At 220 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 322 series at 220 mm bore (400×114 mm) is a wider, higher-capacity section than 30244; do not substitute without re-checking shaft shoulder diameters and pair setting.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32244 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Setting is a design value, not an assembly feel: excessive preload in the 32244 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 400 mm cup race release as noise within the first running hours.", "The 1720/2700 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32244 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32244 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32244?", "a": "The SKF 32244 is a single-row tapered roller bearing with 220 mm bore, 400 mm outer diameter and 114 mm width (8.661 × 15.748 × 4.488 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1720 kN, C0 2700 kN, fatigue load limit Pu 232 kN, reference speed 1,100 r/min, limiting speed 1,500 r/min, mass about 59500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32244 bore code work?", "a": "The last two digits of 32244 are bore code 44, so 44 × 5 = 220 mm bore. The 400 mm OD and 114 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32244 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32244 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32244 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32244 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32244", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32244" ], "locale_variants": {} }, { "sku": "322-28", "brand": "SKF", "manufacturer_designation": "SKF 322/28 B", "series": "32200-series", "type": "tapered_roller", "d_mm": 28, "D_mm": 58, "B_mm": 20.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 51.9, "static_load_kN": 50, "fatigue_load_limit_kN": 5.5, "max_rpm": 12000, "reference_speed_rpm": 9500, "limiting_speed_rpm": 12000, "weight_g": 250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 322/28 B belongs to the SKF single-row tapered roller range — the 28 mm bore entry in the 32200 series, dimensioned 58 mm OD and 20.25 mm wide to the ISO 355 boundary plan.Numbering ties the bearing to its envelope: 322 means tapered-roller type 3, heavy section series 22, 28 mm bore — which is why the 58×20.25 mm outline swaps dimensionally with other ISO 355 bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Speed planning uses two different ceilings: 9,500 r/min thermal reference and 12,000 r/min mechanical limiting speed. For a 28 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 322 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Material and manufacturing detail: the 250 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 32200 ISO envelope, with the pressed-steel cage contributing roughly 8 g of the total; the 28 mm bore is ground to IT5 roundness and the 58 mm OD to IT5 cylindricity, and the 20.25 mm width tolerance keeps the pair-setting scatter within the ISO preload class.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 28 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 322 pair heats, loses setting control and smears the roller-rib contact.", "The 322 series at 28 mm bore (58×20.25 mm) is a wider, higher-capacity section than 30222; do not substitute without re-checking shaft shoulder diameters and pair setting.", "Setting is a design value, not an assembly feel: excessive preload in the 322 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Setting is a design value, not an assembly feel: excessive preload in the 322 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Open 322 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 51.9/50 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 322 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 322/28 B designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 322?", "a": "The SKF 322/28 B is a single-row tapered roller bearing with 28 mm bore, 58 mm outer diameter and 20.25 mm width (1.102 × 2.283 × 0.797 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 51.9 kN, C0 50 kN, fatigue load limit Pu 5.5 kN, reference speed 9,500 r/min, limiting speed 12,000 r/min, mass about 250 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 322 bore code work?", "a": "Non-standard bore sizes like 322 give the bore directly in millimetres after the slash, so 22 here means a 28 mm bore rather than a code × 5 value. The 58 mm OD and 20.25 mm width still follow the ISO 355 dimension-series plan for the 320 family." }, { "q": "What do the 322 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 322 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 322 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 322 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "322-28", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "322-28" ], "locale_variants": {} }, { "sku": "32911", "brand": "SKF", "manufacturer_designation": "SKF 32911", "series": "32900-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 80, "B_mm": 17, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 51.7, "static_load_kN": 69.5, "fatigue_load_limit_kN": 7.2, "max_rpm": 7500, "reference_speed_rpm": 6300, "limiting_speed_rpm": 7500, "weight_g": 280, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 32911 appears as SKF 32911: an open, single-row tapered roller bearing in the very-light thin section of the 32900 dimension series, supplied with a pressed-steel cage as standard.The code breaks down as type prefix 3 (tapered roller), series 29 (the very-light thin section), and bore code 11 = 55 mm; dimensions 55×80×17 mm therefore match the ISO 355 envelope. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. 2BC); it is the dimensional series, not a separate part number. The 12.5 mm radial section height ((80−55)/2) and 280 g catalogue mass frame a 55 mm bore bearing rated at 51.7 kN C — roughly 0.94 kN of dynamic capacity per millimetre of bore before application factors. Mounting practice for 32911: the rotating cone takes the interference fit (k5 on a 55 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Load system: the 51.7 kN basic dynamic rating C and 69.5 kN static rating C0 give a C0/C balance of 1.34, and dividing C by the 55 mm bore yields 0.94 kN per millimetre of journal — a density metric that compares across families; the 7.2 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 55 mm shaft carrying variable duty.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "On this 55 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 32911 pair heats, loses setting control and smears the roller-rib contact.", "The 329 series at 55 mm bore (80×17 mm) is the very-light thin-section envelope: the smallest OD of any tapered family at this bore, ideal where radial space is severely limited, but capacity is well below a 30211 of the same bore — confirm the L10 life and minimum axial load before choosing it.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32911 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Setting is a design value, not an assembly feel: excessive preload in the 32911 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 51.7/69.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32911 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32911 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32911?", "a": "The SKF 32911 is a single-row tapered roller bearing with 55 mm bore, 80 mm outer diameter and 17 mm width (2.165 × 3.15 × 0.669 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 51.7 kN, C0 69.5 kN, fatigue load limit Pu 7.2 kN, reference speed 6,300 r/min, limiting speed 7,500 r/min, mass about 280 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32911 bore code work?", "a": "The last two digits of 32911 are bore code 11, so 11 × 5 = 55 mm bore. The 80 mm OD and 17 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32911 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 29 is the ISO 355 series (very-light thin section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32911 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32911 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32911 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32911", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32911" ], "locale_variants": {} }, { "sku": "32920", "brand": "SKF", "manufacturer_designation": "SKF 32920", "series": "32900-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 140, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 147, "static_load_kN": 204, "fatigue_load_limit_kN": 22.4, "max_rpm": 4300, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4300, "weight_g": 1150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 100 mm shaft carrying combined load, SKF lists 32920 under catalogue execution SKF 32920: one open single-row tapered roller bearing in the very-light thin section of the 32900 family.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 29 is the ISO 355 diameter/width series (very-light thin section), and the last two digits encode the 100 mm bore; the 140 mm OD and 25 mm width follow the ISO 355 general plan. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. 2CC); it is the dimensional series, not a separate part number. Speed planning uses two different ceilings: 3,400 r/min thermal reference and 4,300 r/min mechanical limiting speed. Because the contact line is tapered, one 32920 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 100 mm shaft typically takes a k5 seat with an H7 housing bore. Cross-section geometry: the 20.0 mm half-section ((140−100)/2) of this 32900-series unit places the roller large-end pitch diameter at roughly 120 mm, and the 25 mm axial width is split between cone (14 mm) and cup rib (11 mm) — a geometry that sets the contact angle and, with the 1150 g rotating cone mass, the critical speed at which cage-roller imbalance begins.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Mount the 100 mm bore 32920 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 329 series at 100 mm bore (140×25 mm) is the very-light thin-section envelope: the smallest OD of any tapered family at this bore, ideal where radial space is severely limited, but capacity is well below a 30220 of the same bore — confirm the L10 life and minimum axial load before choosing it.", "Setting is a design value, not an assembly feel: excessive preload in the 32920 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Setting is a design value, not an assembly feel: excessive preload in the 32920 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Catalogue reference speed and limiting speed are different limits: the 3,400 r/min reference is a thermal criterion under load, while the 4,300 r/min limiting value is the mechanical ceiling — observe both.", "The 147/204 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32920 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32920 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32920?", "a": "The SKF 32920 is a single-row tapered roller bearing with 100 mm bore, 140 mm outer diameter and 25 mm width (3.937 × 5.512 × 0.984 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 147 kN, C0 204 kN, fatigue load limit Pu 22.4 kN, reference speed 3,400 r/min, limiting speed 4,300 r/min, mass about 1150 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32920 bore code work?", "a": "The last two digits of 32920 are bore code 20, so 20 × 5 = 100 mm bore. The 140 mm OD and 25 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32920 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 29 is the ISO 355 series (very-light thin section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32920 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32920 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32920 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32920-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 100×140×25 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "32920", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32920" ], "locale_variants": {} }, { "sku": "32924", "brand": "SKF", "manufacturer_designation": "SKF 32924", "series": "32900-series", "type": "tapered_roller", "d_mm": 120, "D_mm": 165, "B_mm": 29, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 204, "static_load_kN": 305, "fatigue_load_limit_kN": 32, "max_rpm": 3600, "reference_speed_rpm": 3000, "limiting_speed_rpm": 3600, "weight_g": 1800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 32924 is a 120×165×29 mm single-row tapered roller bearing — the very-light thin section entry in the 32900 series, with an asymmetric raceway cut for thrust capacity and separable mounting.The code breaks down as type prefix 3 (tapered roller), series 29 (the very-light thin section), and bore code 24 = 120 mm; dimensions 120×165×29 mm therefore match the ISO 355 envelope. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. 2CC); it is the dimensional series, not a separate part number. The 22.5 mm radial section height ((165−120)/2) and 1800 g catalogue mass frame a 120 mm bore bearing rated at 204 kN C — roughly 1.70 kN of dynamic capacity per millimetre of bore before application factors. A single 32924 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Material and manufacturing detail: the 1800 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 32900 ISO envelope, with the pressed-steel cage contributing roughly 54 g of the total; the 120 mm bore is ground to IT5 roundness and the 165 mm OD to IT5 cylindricity, and the 29 mm width tolerance keeps the pair-setting scatter within the ISO preload class.", "applications": [ "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "At 120 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 329 series at 120 mm bore (165×29 mm) is the very-light thin-section envelope: the smallest OD of any tapered family at this bore, ideal where radial space is severely limited, but capacity is well below a 30224 of the same bore — confirm the L10 life and minimum axial load before choosing it.", "Do not mix brands or executions inside one 32924 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Do not mix brands or executions inside one 32924 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The 1800 g mass and 29 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 32924.", "The 204/305 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32924 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32924 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32924?", "a": "The SKF 32924 is a single-row tapered roller bearing with 120 mm bore, 165 mm outer diameter and 29 mm width (4.724 × 6.496 × 1.142 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 204 kN, C0 305 kN, fatigue load limit Pu 32 kN, reference speed 3,000 r/min, limiting speed 3,600 r/min, mass about 1800 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32924 bore code work?", "a": "The last two digits of 32924 are bore code 24, so 24 × 5 = 120 mm bore. The 165 mm OD and 29 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32924 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 29 is the ISO 355 series (very-light thin section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32924 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32924 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32924 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32924-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 120×165×29 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "32924", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32924" ], "locale_variants": {} }, { "sku": "32926", "brand": "SKF", "manufacturer_designation": "SKF 32926", "series": "32900-series", "type": "tapered_roller", "d_mm": 130, "D_mm": 180, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 245, "static_load_kN": 365, "fatigue_load_limit_kN": 38, "max_rpm": 3200, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3200, "weight_g": 2400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32926 belongs to the SKF single-row tapered roller range — the 130 mm bore entry in the 32900 series, dimensioned 180 mm OD and 32 mm wide to the ISO 355 boundary plan.Digit by digit, 32926 reads as bearing type 3 (single-row tapered roller), very-light thin section series 29, and bore reference 26 resolving to 130 mm; 180 mm OD and 32 mm width are the matching ISO 355 boundary values. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. 2CC); it is the dimensional series, not a separate part number. At 2,600 r/min reference speed the 25.0 mm-section 32926 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 3,200 r/min as the mechanical ceiling. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 32926 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Operating context for the 130 mm bore: a shaft of this diameter in the xl-bore band typically runs between 104000 and 156000 r/min in real machinery, and the 180 mm outside diameter places the housing shoulder at 188 mm outer abutment; the 32 mm width and 2400 g mass together set the shaft critical speed and the housing resonance check for this 32900-series envelope.", "applications": [ "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "At 130 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 329 series at 130 mm bore (180×32 mm) is the very-light thin-section envelope: the smallest OD of any tapered family at this bore, ideal where radial space is severely limited, but capacity is well below a 30226 of the same bore — confirm the L10 life and minimum axial load before choosing it.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32926 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32926 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Shaft and housing fillets must clear the bearing chamfer so the 32 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 245/365 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32926 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32926 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32926?", "a": "The SKF 32926 is a single-row tapered roller bearing with 130 mm bore, 180 mm outer diameter and 32 mm width (5.118 × 7.087 × 1.26 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 245 kN, C0 365 kN, fatigue load limit Pu 38 kN, reference speed 2,600 r/min, limiting speed 3,200 r/min, mass about 2400 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32926 bore code work?", "a": "The last two digits of 32926 are bore code 26, so 26 × 5 = 130 mm bore. The 180 mm OD and 32 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32926 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 29 is the ISO 355 series (very-light thin section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32926 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32926 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32926 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32926-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 130×180×32 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "32926", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32926" ], "locale_variants": {} }, { "sku": "32928", "brand": "SKF", "manufacturer_designation": "SKF 32928", "series": "32900-series", "type": "tapered_roller", "d_mm": 140, "D_mm": 190, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 252, "static_load_kN": 390, "fatigue_load_limit_kN": 40, "max_rpm": 3000, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3000, "weight_g": 2550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32928 (SKF 32928) is the very-light thin section tapered roller choice for a 140 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 190×32 mm ISO 355 envelope.On the SKF nameplate, 32928 follows the ISO 355 convention: 3 for the tapered-roller type, 29 for the very-light thin section, final digits 28 for the 140 mm bore. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. 2CC); it is the dimensional series, not a separate part number. With C 252 kN and C0 390 kN, the 32928 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 3,000 r/min. For a 140 mm shaft the usual cone seat is m6 with an H7 housing when the inner ring rotates; arrange two 32928 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Journal and housing interface: the 140 mm bore takes a m6 shaft seat (upper deviation ~0.280 mm for this diameter range) and the 190 mm outside diameter pairs with an H7 housing bore tolerance band of 190.000/190.020 mm; the 32 mm width defines the shoulder depth, and the 2550 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations.", "applications": [ "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "At 140 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 329 series at 140 mm bore (190×32 mm) is the very-light thin-section envelope: the smallest OD of any tapered family at this bore, ideal where radial space is severely limited, but capacity is well below a 30228 of the same bore — confirm the L10 life and minimum axial load before choosing it.", "A single 32928 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "A single 32928 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The 32928 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 252/390 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32928 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32928 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32928?", "a": "The SKF 32928 is a single-row tapered roller bearing with 140 mm bore, 190 mm outer diameter and 32 mm width (5.512 × 7.48 × 1.26 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 252 kN, C0 390 kN, fatigue load limit Pu 40 kN, reference speed 2,600 r/min, limiting speed 3,000 r/min, mass about 2550 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32928 bore code work?", "a": "The last two digits of 32928 are bore code 28, so 28 × 5 = 140 mm bore. The 190 mm OD and 32 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32928 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 29 is the ISO 355 series (very-light thin section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32928 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32928 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32928 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32928", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32928" ], "locale_variants": {} }, { "sku": "32934", "brand": "SKF", "manufacturer_designation": "SKF 32934", "series": "32900-series", "type": "tapered_roller", "d_mm": 170, "D_mm": 230, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 351, "static_load_kN": 585, "fatigue_load_limit_kN": 55, "max_rpm": 2400, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2400, "weight_g": 4500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 170 mm shaft carrying combined load, SKF lists 32934 under catalogue execution SKF 32934: one open single-row tapered roller bearing in the very-light thin section of the 32900 family.Digit by digit, 32934 reads as bearing type 3 (single-row tapered roller), very-light thin section series 29, and bore reference 34 resolving to 170 mm; 230 mm OD and 38 mm width are the matching ISO 355 boundary values. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. 3DC); it is the dimensional series, not a separate part number. With C 351 kN and C0 585 kN, the 32934 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 2,400 r/min. Fit selection follows the rotating ring — interference on a rotating cone — and two 32934 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Speed envelope and thermal behaviour: at 2,000 r/min thermal reference, the 170 mm bore shaft runs at a dn of 340k, and the 30.0 mm section dissipates heat through the cup-to-housing contact path; the 2,400 r/min mechanical ceiling reflects cage strength, and the 4500 g spinning cone contributes gyroscopic moment under rapid speed reversal.", "applications": [ "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "At 170 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 329 series at 170 mm bore (230×38 mm) is the very-light thin-section envelope: the smallest OD of any tapered family at this bore, ideal where radial space is severely limited, but capacity is well below a 30234 of the same bore — confirm the L10 life and minimum axial load before choosing it.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32934 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32934 mounting error.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 230 mm cup race release as noise within the first running hours.", "The 351/585 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32934 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32934 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32934?", "a": "The SKF 32934 is a single-row tapered roller bearing with 170 mm bore, 230 mm outer diameter and 38 mm width (6.693 × 9.055 × 1.496 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 351 kN, C0 585 kN, fatigue load limit Pu 55 kN, reference speed 2,000 r/min, limiting speed 2,400 r/min, mass about 4500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32934 bore code work?", "a": "The last two digits of 32934 are bore code 34, so 34 × 5 = 170 mm bore. The 230 mm OD and 38 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32934 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 29 is the ISO 355 series (very-light thin section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32934 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32934 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32934 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32934", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32934" ], "locale_variants": {} }, { "sku": "32936", "brand": "SKF", "manufacturer_designation": "SKF 32936", "series": "32900-series", "type": "tapered_roller", "d_mm": 180, "D_mm": 250, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 435, "static_load_kN": 735, "fatigue_load_limit_kN": 68, "max_rpm": 2200, "reference_speed_rpm": 1900, "limiting_speed_rpm": 2200, "weight_g": 6650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF 32936 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 180 mm shaft, very-light thin section, with an open pressed-steel-cage execution and one-direction axial capacity.On the SKF nameplate, 32936 follows the ISO 355 convention: 3 for the tapered-roller type, 29 for the very-light thin section, final digits 36 for the 180 mm bore. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. 4DC); it is the dimensional series, not a separate part number. Selection arithmetic: the C0/C ratio is about 1.69 (static 735 kN against dynamic 435 kN), typical of a tapered roller sized for axial capacity, and the 68 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 32936 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Material and manufacturing detail: the 6650 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 32900 ISO envelope, with the pressed-steel cage contributing roughly 200 g of the total; the 180 mm bore is ground to IT5 roundness and the 250 mm OD to IT5 cylindricity, and the 45 mm width tolerance keeps the pair-setting scatter within the ISO preload class.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "At 180 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 329 series at 180 mm bore (250×45 mm) is the very-light thin-section envelope: the smallest OD of any tapered family at this bore, ideal where radial space is severely limited, but capacity is well below a 30236 of the same bore — confirm the L10 life and minimum axial load before choosing it.", "A single 32936 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Setting is a design value, not an assembly feel: excessive preload in the 32936 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The 6650 g mass and 45 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 32936.", "The 435/735 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32936 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32936 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32936?", "a": "The SKF 32936 is a single-row tapered roller bearing with 180 mm bore, 250 mm outer diameter and 45 mm width (7.087 × 9.843 × 1.772 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 435 kN, C0 735 kN, fatigue load limit Pu 68 kN, reference speed 1,900 r/min, limiting speed 2,200 r/min, mass about 6650 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32936 bore code work?", "a": "The last two digits of 32936 are bore code 36, so 36 × 5 = 180 mm bore. The 250 mm OD and 45 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32936 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 29 is the ISO 355 series (very-light thin section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32936 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32936 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32936 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32936", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32936" ], "locale_variants": {} }, { "sku": "32938", "brand": "SKF", "manufacturer_designation": "SKF 32938", "series": "32900-series", "type": "tapered_roller", "d_mm": 190, "D_mm": 260, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 443, "static_load_kN": 765, "fatigue_load_limit_kN": 72, "max_rpm": 2200, "reference_speed_rpm": 1800, "limiting_speed_rpm": 2200, "weight_g": 7000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 32938 is a 190×260×45 mm single-row tapered roller bearing — the very-light thin section entry in the 32900 series, with an asymmetric raceway cut for thrust capacity and separable mounting.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 29 is the ISO 355 diameter/width series (very-light thin section), and the last two digits encode the 190 mm bore; the 260 mm OD and 45 mm width follow the ISO 355 general plan. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. 4DC); it is the dimensional series, not a separate part number. Catalogue mass 7000 g for the 190×260×45 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Because the contact line is tapered, one 32938 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 190 mm shaft typically takes a m6 seat with an H7 housing bore. Operating context for the 190 mm bore: a shaft of this diameter in the xl-bore band typically runs between 152000 and 228000 r/min in real machinery, and the 260 mm outside diameter places the housing shoulder at 268 mm outer abutment; the 45 mm width and 7000 g mass together set the shaft critical speed and the housing resonance check for this 32900-series envelope.", "applications": [ "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "At 190 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 329 series at 190 mm bore (260×45 mm) is the very-light thin-section envelope: the smallest OD of any tapered family at this bore, ideal where radial space is severely limited, but capacity is well below a 30238 of the same bore — confirm the L10 life and minimum axial load before choosing it.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32938 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "At the 443 kN rating of 32938, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 2,200 r/min speed end and heavier preload only where moment stiffness dominates.", "Shaft and housing fillets must clear the bearing chamfer so the 45 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 443/765 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32938 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32938 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32938?", "a": "The SKF 32938 is a single-row tapered roller bearing with 190 mm bore, 260 mm outer diameter and 45 mm width (7.48 × 10.236 × 1.772 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 443 kN, C0 765 kN, fatigue load limit Pu 72 kN, reference speed 1,800 r/min, limiting speed 2,200 r/min, mass about 7000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32938 bore code work?", "a": "The last two digits of 32938 are bore code 38, so 38 × 5 = 190 mm bore. The 260 mm OD and 45 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32938 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 29 is the ISO 355 series (very-light thin section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32938 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32938 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32938 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32938-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 190×260×45 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "32938", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32938" ], "locale_variants": {} }, { "sku": "32940", "brand": "SKF", "manufacturer_designation": "SKF 32940", "series": "32900-series", "type": "tapered_roller", "d_mm": 200, "D_mm": 280, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 588, "static_load_kN": 950, "fatigue_load_limit_kN": 88, "max_rpm": 2000, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2000, "weight_g": 9500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32940 belongs to the SKF single-row tapered roller range — the 200 mm bore entry in the 32900 series, dimensioned 280 mm OD and 51 mm wide to the ISO 355 boundary plan.The code breaks down as type prefix 3 (tapered roller), series 29 (the very-light thin section), and bore code 40 = 200 mm; dimensions 200×280×51 mm therefore match the ISO 355 envelope. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. 3EC); it is the dimensional series, not a separate part number. With C 588 kN and C0 950 kN, the 32940 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 2,000 r/min. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 32940 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Load system: the 588 kN basic dynamic rating C and 950 kN static rating C0 give a C0/C balance of 1.62, and dividing C by the 200 mm bore yields 2.94 kN per millimetre of journal — a density metric that compares across families; the 88 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 200 mm shaft carrying variable duty.", "applications": [ "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At 200 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 329 series at 200 mm bore (280×51 mm) is the very-light thin-section envelope: the smallest OD of any tapered family at this bore, ideal where radial space is severely limited, but capacity is well below a 30240 of the same bore — confirm the L10 life and minimum axial load before choosing it.", "Do not mix brands or executions inside one 32940 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "At the 588 kN rating of 32940, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 2,000 r/min speed end and heavier preload only where moment stiffness dominates.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 588/950 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32940 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32940 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32940?", "a": "The SKF 32940 is a single-row tapered roller bearing with 200 mm bore, 280 mm outer diameter and 51 mm width (7.874 × 11.024 × 2.008 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 588 kN, C0 950 kN, fatigue load limit Pu 88 kN, reference speed 1,700 r/min, limiting speed 2,000 r/min, mass about 9500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32940 bore code work?", "a": "The last two digits of 32940 are bore code 40, so 40 × 5 = 200 mm bore. The 280 mm OD and 51 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32940 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 29 is the ISO 355 series (very-light thin section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32940 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32940 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32940 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32940", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32940" ], "locale_variants": {} }, { "sku": "32944", "brand": "SKF", "manufacturer_designation": "SKF 32944", "series": "32900-series", "type": "tapered_roller", "d_mm": 220, "D_mm": 300, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 601, "static_load_kN": 1000, "fatigue_load_limit_kN": 91.5, "max_rpm": 1900, "reference_speed_rpm": 1500, "limiting_speed_rpm": 1900, "weight_g": 10000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32944 is a single-row tapered roller bearing in the ISO 32900 dimension series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.On the SKF nameplate, 32944 follows the ISO 355 convention: 3 for the tapered-roller type, 29 for the very-light thin section, final digits 44 for the 220 mm bore. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. 3EC); it is the dimensional series, not a separate part number. Catalogue mass 10000 g for the 220×300×51 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Mounting practice for 32944: the rotating cone takes the interference fit (m6 on a 220 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Cross-section geometry: the 40.0 mm half-section ((300−220)/2) of this 32900-series unit places the roller large-end pitch diameter at roughly 260 mm, and the 51 mm axial width is split between cone (28 mm) and cup rib (23 mm) — a geometry that sets the contact angle and, with the 10000 g rotating cone mass, the critical speed at which cage-roller imbalance begins.", "applications": [ "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At 220 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 329 series at 220 mm bore (300×51 mm) is the very-light thin-section envelope: the smallest OD of any tapered family at this bore, ideal where radial space is severely limited, but capacity is well below a 30244 of the same bore — confirm the L10 life and minimum axial load before choosing it.", "A single 32944 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 32944 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Catalogue reference speed and limiting speed are different limits: the 1,500 r/min reference is a thermal criterion under load, while the 1,900 r/min limiting value is the mechanical ceiling — observe both.", "The 601/1000 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32944 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32944 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32944?", "a": "The SKF 32944 is a single-row tapered roller bearing with 220 mm bore, 300 mm outer diameter and 51 mm width (8.661 × 11.811 × 2.008 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 601 kN, C0 1000 kN, fatigue load limit Pu 91.5 kN, reference speed 1,500 r/min, limiting speed 1,900 r/min, mass about 10000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32944 bore code work?", "a": "The last two digits of 32944 are bore code 44, so 44 × 5 = 220 mm bore. The 300 mm OD and 51 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32944 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 29 is the ISO 355 series (very-light thin section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32944 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32944 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32944 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32944", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32944" ], "locale_variants": {} }, { "sku": "32948", "brand": "SKF", "manufacturer_designation": "SKF 32948", "series": "32900-series", "type": "tapered_roller", "d_mm": 240, "D_mm": 320, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 624, "static_load_kN": 1080, "fatigue_load_limit_kN": 96.5, "max_rpm": 1700, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1700, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 240 mm shaft carrying combined load, SKF lists 32948 under catalogue execution SKF 32948: one open single-row tapered roller bearing in the very-light thin section of the 32900 family.Numbering ties the bearing to its envelope: 32948 means tapered-roller type 3, very-light thin section series 29, 240 mm bore — which is why the 320×51 mm outline swaps dimensionally with other ISO 355 bearings of the same code. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. 4EC); it is the dimensional series, not a separate part number. The 96.5 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.73 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 32948 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Material and manufacturing detail: the 11000 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 32900 ISO envelope, with the pressed-steel cage contributing roughly 330 g of the total; the 240 mm bore is ground to IT5 roundness and the 320 mm OD to IT5 cylindricity, and the 51 mm width tolerance keeps the pair-setting scatter within the ISO preload class.", "applications": [ "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "At 240 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 329 series at 240 mm bore (320×51 mm) is the very-light thin-section envelope: the smallest OD of any tapered family at this bore, ideal where radial space is severely limited, but capacity is well below a 30248 of the same bore — confirm the L10 life and minimum axial load before choosing it.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32948 mounting error.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32948 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The 11000 g mass and 51 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 32948.", "The 624/1080 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32948 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32948 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32948?", "a": "The SKF 32948 is a single-row tapered roller bearing with 240 mm bore, 320 mm outer diameter and 51 mm width (9.449 × 12.598 × 2.008 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 624 kN, C0 1080 kN, fatigue load limit Pu 96.5 kN, reference speed 1,400 r/min, limiting speed 1,700 r/min, mass about 11000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32948 bore code work?", "a": "The last two digits of 32948 are bore code 48, so 48 × 5 = 240 mm bore. The 320 mm OD and 51 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32948 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 29 is the ISO 355 series (very-light thin section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32948 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32948 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32948 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32948", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32948" ], "locale_variants": {} }, { "sku": "32960", "brand": "SKF", "manufacturer_designation": "SKF 32960", "series": "32900-series", "type": "tapered_roller", "d_mm": 300, "D_mm": 420, "B_mm": 76, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1126, "static_load_kN": 2240, "fatigue_load_limit_kN": 186, "max_rpm": 1300, "reference_speed_rpm": 950, "limiting_speed_rpm": 1300, "weight_g": 31500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 32960 appears as SKF 32960: an open, single-row tapered roller bearing in the very-light thin section of the 32900 dimension series, supplied with a pressed-steel cage as standard.On the SKF nameplate, 32960 follows the ISO 355 convention: 3 for the tapered-roller type, 29 for the very-light thin section, final digits 60 for the 300 mm bore. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. 3FD); it is the dimensional series, not a separate part number. The 186 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.99 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Fit selection follows the rotating ring — interference on a rotating cone — and two 32960 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Operating context for the 300 mm bore: a shaft of this diameter in the xl-bore band typically runs between 240000 and 360000 r/min in real machinery, and the 420 mm outside diameter places the housing shoulder at 428 mm outer abutment; the 76 mm width and 31500 g mass together set the shaft critical speed and the housing resonance check for this 32900-series envelope.", "applications": [ "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "At 300 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 329 series at 300 mm bore (420×76 mm) is the very-light thin-section envelope: the smallest OD of any tapered family at this bore, ideal where radial space is severely limited, but capacity is well below a 30260 of the same bore — confirm the L10 life and minimum axial load before choosing it.", "A single 32960 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Do not mix brands or executions inside one 32960 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Shaft and housing fillets must clear the bearing chamfer so the 76 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 1126/2240 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 32960 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32960 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32960?", "a": "The SKF 32960 is a single-row tapered roller bearing with 300 mm bore, 420 mm outer diameter and 76 mm width (11.811 × 16.535 × 2.992 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1126 kN, C0 2240 kN, fatigue load limit Pu 186 kN, reference speed 950 r/min, limiting speed 1,300 r/min, mass about 31500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 32960 bore code work?", "a": "The last two digits of 32960 are bore code 60, so 60 × 5 = 300 mm bore. The 420 mm OD and 76 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 32960 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 29 is the ISO 355 series (very-light thin section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 32960 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 32960 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32960 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "32960", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "32960" ], "locale_variants": {} }, { "sku": "30202", "brand": "SKF", "manufacturer_designation": "SKF 30202", "series": "30200-series", "type": "tapered_roller", "d_mm": 15, "D_mm": 35, "B_mm": 11.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 18.5, "static_load_kN": 14.6, "fatigue_load_limit_kN": 1.43, "max_rpm": 20000, "reference_speed_rpm": 17000, "limiting_speed_rpm": 20000, "weight_g": 55, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 30202 appears as SKF 30202: an open, single-row tapered roller bearing in the standard section of the 30200 dimension series, supplied with a pressed-steel cage as standard.On the SKF nameplate, 30202 follows the ISO 355 convention: 3 for the tapered-roller type, 02 for the standard section, final digits 02 for the 15 mm bore. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. With C 18.5 kN and C0 14.6 kN, the 30202 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 20,000 r/min. Because the contact line is tapered, one 30202 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 15 mm shaft typically takes a j5 seat with an H7 housing bore. Operating context for the 15 mm bore: a shaft of this diameter in the small-bore band typically runs between 12000 and 18000 r/min in real machinery, and the 35 mm outside diameter places the housing shoulder at 43 mm outer abutment; the 11.75 mm width and 55 g mass together set the shaft critical speed and the housing resonance check for this 30200-series envelope.", "applications": [ "steering knuckles and small differentials", "agricultural implement hubs", "small conveyor drive pulleys", "power-tool gear heads" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "At a 15 mm bore the thin cone and cup are easily distorted by an over-tight shaft nut; check seat runout (target Ra ≤ 0.8 µm) and torque the locknut progressively — a pinched 30202 shows up as gearbox vibration long before it fails.", "The 302 series at 15 mm bore (35×11.75 mm) is the standard tapered-roller envelope; stepping to a 32202 or 32302 changes OD, width and heat generation — it is not a drop-in swap when the housing and speed are fixed.", "At the 18.5 kN rating of 30202, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 20,000 r/min speed end and heavier preload only where moment stiffness dominates.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 30202 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The 55 g mass and 11.75 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 30202.", "The 18.5/14.6 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 30202 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 30202 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30202?", "a": "The SKF 30202 is a single-row tapered roller bearing with 15 mm bore, 35 mm outer diameter and 11.75 mm width (0.591 × 1.378 × 0.463 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 18.5 kN, C0 14.6 kN, fatigue load limit Pu 1.43 kN, reference speed 17,000 r/min, limiting speed 20,000 r/min, mass about 55 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 30202 bore code work?", "a": "The last two digits of 30202 are bore code 02, one of the small special codes: 00 = 10 mm, 01 = 12 mm, 02 = 15 mm, 03 = 17 mm — here 02 = 15 mm bore. The 35 mm OD and 11.75 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 30202 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 02 is the ISO 355 series (standard section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 30202 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 30202 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 30202 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "30202", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "30202" ], "locale_variants": {} }, { "sku": "30203", "brand": "SKF", "manufacturer_designation": "SKF 30203", "series": "30200-series", "type": "tapered_roller", "d_mm": 17, "D_mm": 40, "B_mm": 13.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 23.4, "static_load_kN": 18.6, "fatigue_load_limit_kN": 1.83, "max_rpm": 18000, "reference_speed_rpm": 15000, "limiting_speed_rpm": 18000, "weight_g": 79, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 30203 belongs to the SKF single-row tapered roller range — the 17 mm bore entry in the 30200 series, dimensioned 40 mm OD and 13.25 mm wide to the ISO 355 boundary plan.The code breaks down as type prefix 3 (tapered roller), series 02 (the standard section), and bore code 03 = 17 mm; dimensions 17×40×13.25 mm therefore match the ISO 355 envelope. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 1.83 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 0.79 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. For a 17 mm shaft the usual cone seat is j5 with an H7 housing when the inner ring rotates; arrange two 30203 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Material and manufacturing detail: the 79 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 30200 ISO envelope, with the pressed-steel cage contributing roughly 2 g of the total; the 17 mm bore is ground to IT5 roundness and the 40 mm OD to IT5 cylindricity, and the 13.25 mm width tolerance keeps the pair-setting scatter within the ISO preload class.", "applications": [ "small conveyor drive pulleys", "power-tool gear heads", "small automotive wheel hubs and trailer axles", "light-duty gearbox input/output shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "At a 17 mm bore the thin cone and cup are easily distorted by an over-tight shaft nut; check seat runout (target Ra ≤ 0.8 µm) and torque the locknut progressively — a pinched 30203 shows up as gearbox vibration long before it fails.", "The 302 series at 17 mm bore (40×13.25 mm) is the standard tapered-roller envelope; stepping to a 32203 or 32303 changes OD, width and heat generation — it is not a drop-in swap when the housing and speed are fixed.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 30203 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Setting is a design value, not an assembly feel: excessive preload in the 30203 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Open 30203 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 23.4/18.6 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 30203 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 30203 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30203?", "a": "The SKF 30203 is a single-row tapered roller bearing with 17 mm bore, 40 mm outer diameter and 13.25 mm width (0.669 × 1.575 × 0.522 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 23.4 kN, C0 18.6 kN, fatigue load limit Pu 1.83 kN, reference speed 15,000 r/min, limiting speed 18,000 r/min, mass about 79 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 30203 bore code work?", "a": "The last two digits of 30203 are bore code 03, one of the small special codes: 00 = 10 mm, 01 = 12 mm, 02 = 15 mm, 03 = 17 mm — here 03 = 17 mm bore. The 40 mm OD and 13.25 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 30203 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 02 is the ISO 355 series (standard section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 30203 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 30203 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 30203 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "30203-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "30203", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "30203" ], "locale_variants": {} }, { "sku": "302-28", "brand": "SKF", "manufacturer_designation": "SKF 302/28", "series": "30200-series", "type": "tapered_roller", "d_mm": 28, "D_mm": 58, "B_mm": 17.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 46.6, "static_load_kN": 41.5, "fatigue_load_limit_kN": 4.4, "max_rpm": 12000, "reference_speed_rpm": 10000, "limiting_speed_rpm": 12000, "weight_g": 200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 28 mm shaft carrying combined load, SKF lists 302 under catalogue execution SKF 302/28: one open single-row tapered roller bearing in the standard section of the 30200 family.Reading the designation: the leading 3 marks a single-row tapered roller bearing, the 02 is the ISO 355 diameter/width series (standard section), and the last two digits encode the 28 mm bore; the 58 mm OD and 17.25 mm width follow the ISO 355 general plan. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Selection arithmetic: the C0/C ratio is about 0.89 (static 41.5 kN against dynamic 46.6 kN), typical of a tapered roller sized for axial capacity, and the 4.4 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Fit selection follows the rotating ring — interference on a rotating cone — and two 302 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Material and manufacturing detail: the 200 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 30200 ISO envelope, with the pressed-steel cage contributing roughly 6 g of the total; the 28 mm bore is ground to IT5 roundness and the 58 mm OD to IT5 cylindricity, and the 17.25 mm width tolerance keeps the pair-setting scatter within the ISO preload class.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 28 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 302 pair heats, loses setting control and smears the roller-rib contact.", "The 302 series at 28 mm bore (58×17.25 mm) is the standard tapered-roller envelope; stepping to a 32202 or 32302 changes OD, width and heat generation — it is not a drop-in swap when the housing and speed are fixed.", "At the 46.6 kN rating of 302, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 12,000 r/min speed end and heavier preload only where moment stiffness dominates.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 302 mounting error.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 58 mm cup race release as noise within the first running hours.", "The 46.6/41.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 302 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 302/28 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 302?", "a": "The SKF 302/28 is a single-row tapered roller bearing with 28 mm bore, 58 mm outer diameter and 17.25 mm width (1.102 × 2.283 × 0.679 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 46.6 kN, C0 41.5 kN, fatigue load limit Pu 4.4 kN, reference speed 10,000 r/min, limiting speed 12,000 r/min, mass about 200 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 302 bore code work?", "a": "The last two digits of 302 are bore code 02, one of the small special codes: 00 = 10 mm, 01 = 12 mm, 02 = 15 mm, 03 = 17 mm — here 02 = 28 mm bore. The 58 mm OD and 17.25 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code." }, { "q": "What do the 302 series and basic execution designations mean?", "a": "The leading 3 marks a single-row tapered roller bearing; the second digit 02 is the ISO 355 series (standard section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution." }, { "q": "Can a single 302 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 302 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 302 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "302-28", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 355 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "302-28" ], "locale_variants": {} }, { "sku": "A4059-A4138", "brand": "SKF", "manufacturer_designation": "SKF A 4059/A 4138", "series": "A4000-series", "type": "tapered_roller", "d_mm": 15, "D_mm": 34.988, "B_mm": 10.998, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 16.5, "static_load_kN": 13.2, "fatigue_load_limit_kN": 1.29, "max_rpm": 22000, "reference_speed_rpm": 17000, "limiting_speed_rpm": 22000, "weight_g": 51, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Cone-and-cup identity in A4059: the leading A 4059 reference identifies the inner ring, rollers and cage; the trailing A 4138 reference identifies the outer ring. The A4000-series series lists alternative cups for the same cone, each producing a different 34.988 mm OD or 10.998 mm width — hence a different SKU even though the bore stays at 15 mm.Ordering number SKF A 4059/A 4138 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 15 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.The A4000-series series assigns 15 mm bore, 34.988 mm OD and 10.998 mm width to A4059; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. In SKF suffix language a bare A4059 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Speed planning uses two different ceilings: 17,000 r/min thermal reference and 22,000 r/min mechanical limiting speed. Specify pairs rather than single units wherever thrust reverses: the tapered contact of A4059 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Load system: the 16.5 kN basic dynamic rating C and 13.2 kN static rating C0 give a C0/C balance of 0.80, and dividing C by the 15 mm bore yields 1.10 kN per millimetre of journal — a density metric that compares across families; the 1.29 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 15 mm shaft carrying variable duty.", "applications": [ "electric-motor pinion shafts", "steering knuckles and small differentials", "agricultural implement hubs", "small automotive wheel hubs and trailer axles" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "At a 15 mm bore the thin cone and cup are easily distorted by an over-tight shaft nut; check seat runout (target Ra ≤ 0.8 µm) and torque the locknut progressively — a pinched A4059 shows up as gearbox vibration long before it fails.", "The A4000-series inch series at 15 mm bore (34.988×10.998 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common A4059 mounting error.", "Do not mix brands or executions inside one A4059 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Open A4059 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 16.5/13.2 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of A4059 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF A 4059/A 4138 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is A4059 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of A4059?", "a": "The SKF A 4059/A 4138 is a single-row tapered roller bearing with 15 mm bore, 34.988 mm outer diameter and 10.998 mm width (0.591 × 1.377 × 0.433 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 16.5 kN, C0 13.2 kN, fatigue load limit Pu 1.29 kN, reference speed 17,000 r/min, limiting speed 22,000 r/min, mass about 51 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the A4059 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the A4000-series code marks the dimensional series. The metric dimensions 15×34.988×10.998 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in A4059 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (A4000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single A4059 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "A4059-A4138-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 15×34.988×10.998 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "A4059-A4138", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "A4059-A4138" ], "locale_variants": {} }, { "sku": "11590-11520", "brand": "SKF", "manufacturer_designation": "SKF 11590/11520", "series": "11500-series", "type": "tapered_roller", "d_mm": 15.875, "D_mm": 42.862, "B_mm": 14.288, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 21.5, "static_load_kN": 17.6, "fatigue_load_limit_kN": 1.8, "max_rpm": 17000, "reference_speed_rpm": 13000, "limiting_speed_rpm": 17000, "weight_g": 100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The cup reference 11520 is structural, not a suffix: it identifies the outer ring that, combined with the 11590 cone, produces the 15.875/42.862/14.288 mm envelope catalogue-listed as 11590. Quote the cup number in full when ordering — the 11500-series tables contain other cups that fit the same cone but change the bearing.In SKF catalogue PUB BU/P1 17000, 11590 appears as SKF 11590/11520: an open, single-row tapered roller bearing in the 11500-series, supplied with a pressed-steel cage as standard.Reading the designation: 11590 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 11500-series code identifies the dimensional series. The 15.875 mm bore, 42.862 mm OD and 14.288 mm width are the metric equivalents of the inch boundary dimensions. In SKF suffix language a bare 11590 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. With C 21.5 kN and C0 17.6 kN, the 11590 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 17,000 r/min. Because the contact line is tapered, one 11590 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 15.875 mm shaft typically takes a j5 seat with an H7 housing bore. Speed envelope and thermal behaviour: at 13,000 r/min thermal reference, the 15.875 mm bore shaft runs at a dn of 206k, and the 13.5 mm section dissipates heat through the cup-to-housing contact path; the 17,000 r/min mechanical ceiling reflects cage strength, and the 100 g spinning cone contributes gyroscopic moment under rapid speed reversal.", "applications": [ "agricultural implement hubs", "small conveyor drive pulleys", "power-tool gear heads", "electric-motor pinion shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "At a 15.875 mm bore the thin cone and cup are easily distorted by an over-tight shaft nut; check seat runout (target Ra ≤ 0.8 µm) and torque the locknut progressively — a pinched 11590 shows up as gearbox vibration long before it fails.", "The 11500-series inch series at 15.875 mm bore (42.862×14.288 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 21.5 kN rating of 11590, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 17,000 r/min speed end and heavier preload only where moment stiffness dominates.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 11590 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 42.862 mm cup race release as noise within the first running hours.", "The 21.5/17.6 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 11590 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 11590/11520 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 11590 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 11590?", "a": "The SKF 11590/11520 is a single-row tapered roller bearing with 15.875 mm bore, 42.862 mm outer diameter and 14.288 mm width (0.625 × 1.687 × 0.563 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 21.5 kN, C0 17.6 kN, fatigue load limit Pu 1.8 kN, reference speed 13,000 r/min, limiting speed 17,000 r/min, mass about 100 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 11590 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 11500-series code marks the dimensional series. The metric dimensions 15.875×42.862×14.288 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 11590 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (11500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 11590 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "11590-11520-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 15.875×42.862×14.288 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "11590-11520", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "11590-11520" ], "locale_variants": {} }, { "sku": "LM11749-710", "brand": "SKF", "manufacturer_designation": "SKF LM 11749/710", "series": "LM11700-series", "type": "tapered_roller", "d_mm": 17.462, "D_mm": 39.878, "B_mm": 13.843, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 26.1, "static_load_kN": 20.8, "fatigue_load_limit_kN": 2.12, "max_rpm": 18000, "reference_speed_rpm": 15000, "limiting_speed_rpm": 18000, "weight_g": 82, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (LM11700-series) ties the pair to a specific boundary plan. Dimensions 17.462×39.878×13.843 mm are the converted metric envelope. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 82 g for the 17.462×39.878×13.843 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of LM11749 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Cross-section geometry: the 11.2 mm half-section ((39.878−17.462)/2) of this LM100-series unit places the roller large-end pitch diameter at roughly 28 mm, and the 13.843 mm axial width is split between cone (8 mm) and cup rib (6 mm) — a geometry that sets the contact angle and, with the 82 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Cone versus cup responsibility in LM11749: the LM 11749 cone carries the 17.462 mm bore, rollers and pressed-steel cage; the 710 cup carries the 39.878 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.In SKF catalogue PUB BU/P1 17000, LM11749 appears as SKF LM 11749/710: an open, single-row tapered roller bearing in the LM11700-series, supplied with a pressed-steel cage as standard.", "applications": [ "steering knuckles and small differentials", "agricultural implement hubs", "small conveyor drive pulleys", "small conveyor drive pulleys" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At a 17.462 mm bore the thin cone and cup are easily distorted by an over-tight shaft nut; check seat runout (target Ra ≤ 0.8 µm) and torque the locknut progressively — a pinched LM11749 shows up as gearbox vibration long before it fails.", "The LM11700-series inch series at 17.462 mm bore (39.878×13.843 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common LM11749 mounting error.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common LM11749 mounting error.", "Catalogue reference speed and limiting speed are different limits: the 15,000 r/min reference is a thermal criterion under load, while the 18,000 r/min limiting value is the mechanical ceiling — observe both.", "The 26.1/20.8 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM11749 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 11749/710 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the LM11749 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM11700-series code marks the dimensional series. The metric dimensions 17.462×39.878×13.843 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM11749 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM11700-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM11749 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM11749 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM11749 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM11749?", "a": "For a rotating shaft under normal load, seat the cone on a j5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 13.843 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "LM11749-LM11710", "equiv_brand": "NTN", "level": "partial", "note": "Same 17.462×39.878×13.843 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "LM11749-710", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM11749-710" ], "locale_variants": {} }, { "sku": "LM11949-910", "brand": "SKF", "manufacturer_designation": "SKF LM 11949/910", "series": "LM11900-series", "type": "tapered_roller", "d_mm": 19.05, "D_mm": 45.237, "B_mm": 15.494, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.8, "static_load_kN": 27.5, "fatigue_load_limit_kN": 2.9, "max_rpm": 16000, "reference_speed_rpm": 13000, "limiting_speed_rpm": 16000, "weight_g": 120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The 2.9 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 0.81 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Specify pairs rather than single units wherever thrust reverses: the tapered contact of LM11949 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Dimensional interchange map: within the LM100 series at 19.05 mm bore, the 45.237 mm OD and 15.494 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 13.1 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 120 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Cone versus cup responsibility in LM11949: the LM 11949 cone carries the 19.05 mm bore, rollers and pressed-steel cage; the 910 cup carries the 45.237 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.The SKF LM 11949/910 is a 19.05×45.237×15.494 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.Reading the designation: LM11949 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the LM11900-series code identifies the dimensional series. The 19.05 mm bore, 45.237 mm OD and 15.494 mm width are the metric equivalents of the inch boundary dimensions. In SKF suffix language a bare LM11949 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately.", "applications": [ "electric-motor pinion shafts", "steering knuckles and small differentials", "agricultural implement hubs", "light-duty gearbox input/output shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At a 19.05 mm bore the thin cone and cup are easily distorted by an over-tight shaft nut; check seat runout (target Ra ≤ 0.8 µm) and torque the locknut progressively — a pinched LM11949 shows up as gearbox vibration long before it fails.", "The LM11900-series inch series at 19.05 mm bore (45.237×15.494 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one LM11949 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common LM11949 mounting error.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 45.237 mm cup race release as noise within the first running hours.", "The 33.8/27.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM11949 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 11949/910 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single LM11949 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM11949 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM11949 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM11949?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 15.494 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM11949 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM11949?", "a": "The SKF LM 11949/910 is a single-row tapered roller bearing with 19.05 mm bore, 45.237 mm outer diameter and 15.494 mm width (0.75 × 1.781 × 0.61 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 33.8 kN, C0 27.5 kN, fatigue load limit Pu 2.9 kN, reference speed 13,000 r/min, limiting speed 16,000 r/min, mass about 120 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "LM11949-LM11910", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "LM11949-910", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM11949-910" ], "locale_variants": {} }, { "sku": "M12649-610", "brand": "SKF", "manufacturer_designation": "SKF M 12649/610", "series": "M12600-series", "type": "tapered_roller", "d_mm": 21.43, "D_mm": 50.005, "B_mm": 17.526, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 45.4, "static_load_kN": 38, "fatigue_load_limit_kN": 4.15, "max_rpm": 15000, "reference_speed_rpm": 12000, "limiting_speed_rpm": 15000, "weight_g": 170, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 21.43 mm shaft carrying combined load, SKF lists M12649 under catalogue execution SKF M 12649/610: one open single-row tapered roller bearing in the inch M12600-series.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (M12600-series) ties the pair to a specific boundary plan. Dimensions 21.43×50.005×17.526 mm are the converted metric envelope. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. At 12,000 r/min reference speed the 14.3 mm-section M12649 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 15,000 r/min as the mechanical ceiling. A single M12649 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Load system: the 45.4 kN basic dynamic rating C and 38 kN static rating C0 give a C0/C balance of 0.84, and dividing C by the 21.43 mm bore yields 2.12 kN per millimetre of journal — a density metric that compares across families; the 4.15 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 21.43 mm shaft carrying variable duty. Inch tapered bearings are matched sets, not mix-and-match components: M12649 pairs the M 12649 cone with the 610 cup under the M12600-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.", "applications": [ "power-tool gear heads", "small automotive wheel hubs and trailer axles", "light-duty gearbox input/output shafts", "power-tool gear heads" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "At a 21.43 mm bore the thin cone and cup are easily distorted by an over-tight shaft nut; check seat runout (target Ra ≤ 0.8 µm) and torque the locknut progressively — a pinched M12649 shows up as gearbox vibration long before it fails.", "The M12600-series inch series at 21.43 mm bore (50.005×17.526 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single M12649 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "At the 45.4 kN rating of M12649, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 15,000 r/min speed end and heavier preload only where moment stiffness dominates.", "Open M12649 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 45.4/38 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of M12649 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF M 12649/610 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of M12649?", "a": "The SKF M 12649/610 is a single-row tapered roller bearing with 21.43 mm bore, 50.005 mm outer diameter and 17.526 mm width (0.844 × 1.969 × 0.69 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 45.4 kN, C0 38 kN, fatigue load limit Pu 4.15 kN, reference speed 12,000 r/min, limiting speed 15,000 r/min, mass about 170 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the M12649 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the M12600-series code marks the dimensional series. The metric dimensions 21.43×50.005×17.526 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in M12649 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (M12600-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single M12649 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does M12649 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load M12649 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "M12649-M12610", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "M12649-610", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "M12649-610" ], "locale_variants": {} }, { "sku": "LM12749-710", "brand": "SKF", "manufacturer_designation": "SKF LM 12749/710", "series": "LM12700-series", "type": "tapered_roller", "d_mm": 22, "D_mm": 45.237, "B_mm": 15.494, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.9, "static_load_kN": 31, "fatigue_load_limit_kN": 3.2, "max_rpm": 15000, "reference_speed_rpm": 12000, "limiting_speed_rpm": 15000, "weight_g": 120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Numbering ties the bearing to its inch-series envelope: LM12749 means a cone and cup matched pair in the LM12700-series series — which is why the 22×45.237×15.494 mm outline swaps dimensionally with other inch-series bearings of the same code. In SKF suffix language a bare LM12749 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. With C 33.9 kN and C0 31 kN, the LM12749 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 15,000 r/min. Mounting practice for LM12749: the rotating cone takes the interference fit (k5 on a 22 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Speed envelope and thermal behaviour: at 12,000 r/min thermal reference, the 22 mm bore shaft runs at a dn of 264k, and the 11.6 mm section dissipates heat through the cup-to-housing contact path; the 15,000 r/min mechanical ceiling reflects cage strength, and the 120 g spinning cone contributes gyroscopic moment under rapid speed reversal. The cup reference 710 is structural, not a suffix: it identifies the outer ring that, combined with the LM 12749 cone, produces the 22/45.237/15.494 mm envelope catalogue-listed as LM12749. Quote the cup number in full when ordering — the LM12700-series tables contain other cups that fit the same cone but change the bearing.LM12749 is a single-row tapered roller bearing in the LM12700-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.", "applications": [ "electric-motor pinion shafts", "steering knuckles and small differentials", "agricultural implement hubs", "agricultural implement hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "At a 22 mm bore the thin cone and cup are easily distorted by an over-tight shaft nut; check seat runout (target Ra ≤ 0.8 µm) and torque the locknut progressively — a pinched LM12749 shows up as gearbox vibration long before it fails.", "The LM12700-series inch series at 22 mm bore (45.237×15.494 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 33.9 kN rating of LM12749, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 15,000 r/min speed end and heavier preload only where moment stiffness dominates.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the LM12749 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 45.237 mm cup race release as noise within the first running hours.", "The 33.9/31 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM12749 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 12749/710 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the LM12749 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM12700-series code marks the dimensional series. The metric dimensions 22×45.237×15.494 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM12749 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM12700-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM12749 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM12749 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM12749 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM12749?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 15.494 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "LM12749-LM12711", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "LM12749-710", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM12749-710" ], "locale_variants": {} }, { "sku": "LM12749-711", "brand": "SKF", "manufacturer_designation": "SKF LM 12749/711", "series": "LM12700-series", "type": "tapered_roller", "d_mm": 22, "D_mm": 45.974, "B_mm": 15.494, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 33.9, "static_load_kN": 31, "fatigue_load_limit_kN": 3.2, "max_rpm": 15000, "reference_speed_rpm": 12000, "limiting_speed_rpm": 15000, "weight_g": 120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " In SKF suffix language a bare LM12749 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 3.2 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 0.91 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. A single LM12749 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Load system: the 33.9 kN basic dynamic rating C and 31 kN static rating C0 give a C0/C balance of 0.91, and dividing C by the 22 mm bore yields 1.54 kN per millimetre of journal — a density metric that compares across families; the 3.2 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 22 mm shaft carrying variable duty. Cone versus cup responsibility in LM12749: the LM 12749 cone carries the 22 mm bore, rollers and pressed-steel cage; the 711 cup carries the 45.974 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.The SKF LM 12749/711 is a 22×45.974×15.494 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.Digit by digit, LM12749 reads as cone reference / cup reference in the LM12700-series inch series; the 22 mm bore, 45.974 mm OD and 15.494 mm width are the metric equivalents of the original inch boundary values.", "applications": [ "steering knuckles and small differentials", "agricultural implement hubs", "small conveyor drive pulleys", "small automotive wheel hubs and trailer axles" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "At a 22 mm bore the thin cone and cup are easily distorted by an over-tight shaft nut; check seat runout (target Ra ≤ 0.8 µm) and torque the locknut progressively — a pinched LM12749 shows up as gearbox vibration long before it fails.", "The LM12700-series inch series at 22 mm bore (45.974×15.494 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single LM12749 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Do not mix brands or executions inside one LM12749 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The LM12749 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 33.9/31 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM12749 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 12749/711 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in LM12749 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM12700-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM12749 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM12749 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM12749 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM12749?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 15.494 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM12749 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "LM12749-LM12711", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "LM12749-711", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM12749-711" ], "locale_variants": {} }, { "sku": "1380-1328", "brand": "SKF", "manufacturer_designation": "SKF 1380/1328", "series": "1300-series", "type": "tapered_roller", "d_mm": 22.225, "D_mm": 52.388, "B_mm": 19.368, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 51.5, "static_load_kN": 44, "fatigue_load_limit_kN": 4.8, "max_rpm": 14000, "reference_speed_rpm": 11000, "limiting_speed_rpm": 14000, "weight_g": 200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Operating context for the 22.225 mm bore: a shaft of this diameter in the small-bore band typically runs between 17780 and 26670 r/min in real machinery, and the 52.388 mm outside diameter places the housing shoulder at 60 mm outer abutment; the 19.368 mm width and 200 g mass together set the shaft critical speed and the housing resonance check for this 13800-series envelope. The cup reference 1328 is structural, not a suffix: it identifies the outer ring that, combined with the 1380 cone, produces the 22.225/52.388/19.368 mm envelope catalogue-listed as 1380. Quote the cup number in full when ordering — the 1300-series tables contain other cups that fit the same cone but change the bearing.SKF 1380 (SKF 1380/1328) is the 1300-series tapered roller choice for a 22.225 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 52.388×19.368 mm envelope.The 1300-series series assigns 22.225 mm bore, 52.388 mm OD and 19.368 mm width to 1380; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. With C 51.5 kN and C0 44 kN, the 1380 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 14,000 r/min. For a 22.225 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 1380 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel.", "applications": [ "small conveyor drive pulleys", "power-tool gear heads", "small automotive wheel hubs and trailer axles", "light-duty gearbox input/output shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At a 22.225 mm bore the thin cone and cup are easily distorted by an over-tight shaft nut; check seat runout (target Ra ≤ 0.8 µm) and torque the locknut progressively — a pinched 1380 shows up as gearbox vibration long before it fails.", "The 1300-series inch series at 22.225 mm bore (52.388×19.368 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 1380 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "A single 1380 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The 200 g mass and 19.368 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 1380.", "The 51.5/44 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 1380 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 1380/1328 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 1380?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 19.368 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 1380 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 1380?", "a": "The SKF 1380/1328 is a single-row tapered roller bearing with 22.225 mm bore, 52.388 mm outer diameter and 19.368 mm width (0.875 × 2.063 × 0.763 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 51.5 kN, C0 44 kN, fatigue load limit Pu 4.8 kN, reference speed 11,000 r/min, limiting speed 14,000 r/min, mass about 200 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 1380 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 1300-series code marks the dimensional series. The metric dimensions 22.225×52.388×19.368 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 1380 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (1300-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "1380-1328-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 22.225×52.388×19.368 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "1380-1329", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "1380-1328", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1380-1328" ], "locale_variants": {} }, { "sku": "L44643-610", "brand": "SKF", "manufacturer_designation": "SKF L 44643/610", "series": "L44600-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 50.292, "B_mm": 14.224, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 32, "static_load_kN": 30, "fatigue_load_limit_kN": 3, "max_rpm": 13000, "reference_speed_rpm": 11000, "limiting_speed_rpm": 13000, "weight_g": 130, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Fit selection follows the rotating ring — interference on a rotating cone — and two L44643 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Cross-section geometry: the 12.4 mm half-section ((50.292−25.4)/2) of this L4400-series unit places the roller large-end pitch diameter at roughly 37 mm, and the 14.224 mm axial width is split between cone (8 mm) and cup rib (6 mm) — a geometry that sets the contact angle and, with the 130 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Within the L44600-series tables, L 44643 appears in several rows because SKF lists multiple cup options for the same cone. L44643 is the 610 variant, with 50.292 mm OD and 14.224 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.Ordering number SKF L 44643/610 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 25.4 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.Numbering ties the bearing to its inch-series envelope: L44643 means a cone and cup matched pair in the L44600-series series — which is why the 25.4×50.292×14.224 mm outline swaps dimensionally with other inch-series bearings of the same code. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. The 3 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 0.94 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "On this 25.4 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight L44643 pair heats, loses setting control and smears the roller-rib contact.", "The L44600-series inch series at 25.4 mm bore (50.292×14.224 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the L44643 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the L44643 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Shaft and housing fillets must clear the bearing chamfer so the 14.224 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 32/30 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of L44643 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF L 44643/610 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does L44643 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load L44643 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit L44643?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 14.224 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is L44643 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of L44643?", "a": "The SKF L 44643/610 is a single-row tapered roller bearing with 25.4 mm bore, 50.292 mm outer diameter and 14.224 mm width (1 × 1.98 × 0.56 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 32 kN, C0 30 kN, fatigue load limit Pu 3 kN, reference speed 11,000 r/min, limiting speed 13,000 r/min, mass about 130 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the L44643 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the L44600-series code marks the dimensional series. The metric dimensions 25.4×50.292×14.224 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "L44643-L44610", "equiv_brand": "NTN", "level": "partial", "note": "Same 25.4×50.292×14.224 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "L44643-610", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "L44643-610" ], "locale_variants": {} }, { "sku": "15578-15520", "brand": "SKF", "manufacturer_designation": "SKF 15578/15520", "series": "15500-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 57.15, "B_mm": 17.462, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 49.1, "static_load_kN": 45.5, "fatigue_load_limit_kN": 4.9, "max_rpm": 12000, "reference_speed_rpm": 10000, "limiting_speed_rpm": 12000, "weight_g": 220, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Cross-section geometry: the 15.9 mm half-section ((57.15−25.4)/2) of this 15500-series unit places the roller large-end pitch diameter at roughly 41 mm, and the 17.462 mm axial width is split between cone (10 mm) and cup rib (8 mm) — a geometry that sets the contact angle and, with the 220 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Inch tapered bearings are matched sets, not mix-and-match components: 15578 pairs the 15578 cone with the 15520 cup under the 15500-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.In SKF catalogue PUB BU/P1 17000, 15578 appears as SKF 15578/15520: an open, single-row tapered roller bearing in the 15500-series, supplied with a pressed-steel cage as standard.In SKF inch-series tables 15578 sits at 25.4 mm bore (1 in) with a 57.15 mm cup OD and 17.462 mm total width — dimensions that trace back to the original Timken boundary plan for the 15500-series family. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Catalogue mass 220 g for the 25.4×57.15×17.462 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 15578 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "On this 25.4 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 15578 pair heats, loses setting control and smears the roller-rib contact.", "The 15500-series inch series at 25.4 mm bore (57.15×17.462 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 15578 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "At the 49.1 kN rating of 15578, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 12,000 r/min speed end and heavier preload only where moment stiffness dominates.", "The 220 g mass and 17.462 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 15578.", "The 49.1/45.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 15578 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 15578/15520 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 15578?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 17.462 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 15578 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 15578?", "a": "The SKF 15578/15520 is a single-row tapered roller bearing with 25.4 mm bore, 57.15 mm outer diameter and 17.462 mm width (1 × 2.25 × 0.687 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 49.1 kN, C0 45.5 kN, fatigue load limit Pu 4.9 kN, reference speed 10,000 r/min, limiting speed 12,000 r/min, mass about 220 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 15578 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 15500-series code marks the dimensional series. The metric dimensions 25.4×57.15×17.462 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 15578 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (15500-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "15578-15520", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "15578-15520" ], "locale_variants": {} }, { "sku": "M84548-510", "brand": "SKF", "manufacturer_designation": "SKF M 84548/510", "series": "M84500-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 57.15, "B_mm": 19.431, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 48.8, "static_load_kN": 45, "fatigue_load_limit_kN": 5, "max_rpm": 12000, "reference_speed_rpm": 10000, "limiting_speed_rpm": 12000, "weight_g": 240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF inch-series tables M84548 sits at 25.4 mm bore (1 in) with a 57.15 mm cup OD and 19.431 mm total width — dimensions that trace back to the original Timken boundary plan for the M84500-series family. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Speed planning uses two different ceilings: 10,000 r/min thermal reference and 12,000 r/min mechanical limiting speed. For a 25.4 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two M84548 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Speed envelope and thermal behaviour: at 10,000 r/min thermal reference, the 25.4 mm bore shaft runs at a dn of 254k, and the 15.9 mm section dissipates heat through the cup-to-housing contact path; the 12,000 r/min mechanical ceiling reflects cage strength, and the 240 g spinning cone contributes gyroscopic moment under rapid speed reversal. Why the cup reference matters here: in the M84500-series tables the M 84548 cone appears against several cup options. M84548 is the pairing with 510, and that choice — not the cone — fixes the 57.15 mm OD, the raceway track position and the 19.431 mm assembled width.Ordering number SKF M 84548/510 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 25.4 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "On this 25.4 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight M84548 pair heats, loses setting control and smears the roller-rib contact.", "The M84500-series inch series at 25.4 mm bore (57.15×19.431 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single M84548 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common M84548 mounting error.", "The M84548 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 48.8/45 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of M84548 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF M 84548/510 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the M84548 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the M84500-series code marks the dimensional series. The metric dimensions 25.4×57.15×19.431 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in M84548 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (M84500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single M84548 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does M84548 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load M84548 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit M84548?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 19.431 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "M84548-M84510", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "M84548-510", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "M84548-510" ], "locale_variants": {} }, { "sku": "15101-15245", "brand": "SKF", "manufacturer_designation": "SKF 15101/15245", "series": "15000-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 62, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 59.5, "static_load_kN": 57, "fatigue_load_limit_kN": 6.2, "max_rpm": 11000, "reference_speed_rpm": 9000, "limiting_speed_rpm": 11000, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Operating context for the 25.4 mm bore: a shaft of this diameter in the medium-bore band typically runs between 20320 and 30480 r/min in real machinery, and the 62 mm outside diameter places the housing shoulder at 70 mm outer abutment; the 19.05 mm width and 300 g mass together set the shaft critical speed and the housing resonance check for this 15100-series envelope. The cup reference 15245 is structural, not a suffix: it identifies the outer ring that, combined with the 15101 cone, produces the 25.4/62/19.05 mm envelope catalogue-listed as 15101. Quote the cup number in full when ordering — the 15000-series tables contain other cups that fit the same cone but change the bearing.The SKF 15101/15245 is a 25.4×62×19.05 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (15000-series) ties the pair to a specific boundary plan. Dimensions 25.4×62×19.05 mm are the converted metric envelope. In SKF suffix language a bare 15101 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Catalogue mass 300 g for the 25.4×62×19.05 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 15101 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "On this 25.4 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 15101 pair heats, loses setting control and smears the roller-rib contact.", "The 15000-series inch series at 25.4 mm bore (62×19.05 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 15101 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "A single 15101 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 59.5/57 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 15101 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 15101/15245 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 15101?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 19.05 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 15101 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 15101?", "a": "The SKF 15101/15245 is a single-row tapered roller bearing with 25.4 mm bore, 62 mm outer diameter and 19.05 mm width (1 × 2.441 × 0.75 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 59.5 kN, C0 57 kN, fatigue load limit Pu 6.2 kN, reference speed 9,000 r/min, limiting speed 11,000 r/min, mass about 300 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 15101 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 15000-series code marks the dimensional series. The metric dimensions 25.4×62×19.05 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 15101 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (15000-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "15101-15243", "equiv_brand": "NTN", "level": "partial", "note": "Same 25.4×62×19.05 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "15101-15245", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "15101-15245" ], "locale_variants": {} }, { "sku": "15103S-15245", "brand": "SKF", "manufacturer_designation": "SKF 15103 S/15245", "series": "15000-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 62, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 59.5, "static_load_kN": 57, "fatigue_load_limit_kN": 6.2, "max_rpm": 11000, "reference_speed_rpm": 9000, "limiting_speed_rpm": 11000, "weight_g": 290, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (15000-series) ties the pair to a specific boundary plan. Dimensions 25.4×62×19.05 mm are the converted metric envelope. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. At 9,000 r/min reference speed the 18.3 mm-section 15103S is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 11,000 r/min as the mechanical ceiling. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 15103S must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Speed envelope and thermal behaviour: at 9,000 r/min thermal reference, the 25.4 mm bore shaft runs at a dn of 229k, and the 18.3 mm section dissipates heat through the cup-to-housing contact path; the 11,000 r/min mechanical ceiling reflects cage strength, and the 290 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cup-side note for 15245: the outer ring's rib profile and the 62 mm outside diameter are cup-specific within the 15000-series tables, so substituting a different cup against the same 15103 S cone changes both the assembled 19.05 mm width and the axial free-play setting of the mounted pair.The SKF 15103 S/15245 is a 25.4×62×19.05 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "On this 25.4 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 15103S pair heats, loses setting control and smears the roller-rib contact.", "The 15000-series inch series at 25.4 mm bore (62×19.05 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 15103S mounting error.", "A single 15103S cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 62 mm cup race release as noise within the first running hours.", "The 59.5/57 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 15103S (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 15103 S/15245 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 15103S inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 15000-series code marks the dimensional series. The metric dimensions 25.4×62×19.05 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 15103S mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (15000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 15103S take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 15103S compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 15103S position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 15103S?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 19.05 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "15103S-15245", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "15103S-15245" ], "locale_variants": {} }, { "sku": "L44649-610", "brand": "SKF", "manufacturer_designation": "SKF L 44649/610", "series": "L44600-series", "type": "tapered_roller", "d_mm": 26.988, "D_mm": 50.292, "B_mm": 14.224, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 32, "static_load_kN": 30, "fatigue_load_limit_kN": 3, "max_rpm": 13000, "reference_speed_rpm": 11000, "limiting_speed_rpm": 13000, "weight_g": 120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. At 11,000 r/min reference speed the 11.7 mm-section L44649 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 13,000 r/min as the mechanical ceiling. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of L44649 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Material and manufacturing detail: the 120 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the L4400 ISO envelope, with the pressed-steel cage contributing roughly 4 g of the total; the 26.988 mm bore is ground to IT5 roundness and the 50.292 mm OD to IT5 cylindricity, and the 14.224 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Why the cup reference matters here: in the L44600-series tables the L 44649 cone appears against several cup options. L44649 is the pairing with 610, and that choice — not the cone — fixes the 50.292 mm OD, the raceway track position and the 14.224 mm assembled width.SKF L 44649/610 belongs to the SKF single-row tapered roller range — the 26.988 mm bore entry in the inch L44600-series, dimensioned 50.292 mm OD and 14.224 mm wide.Digit by digit, L44649 reads as cone reference / cup reference in the L44600-series inch series; the 26.988 mm bore, 50.292 mm OD and 14.224 mm width are the metric equivalents of the original inch boundary values.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "On this 26.988 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight L44649 pair heats, loses setting control and smears the roller-rib contact.", "The L44600-series inch series at 26.988 mm bore (50.292×14.224 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single L44649 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "At the 32 kN rating of L44649, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 13,000 r/min speed end and heavier preload only where moment stiffness dominates.", "Catalogue reference speed and limiting speed are different limits: the 11,000 r/min reference is a thermal criterion under load, while the 13,000 r/min limiting value is the mechanical ceiling — observe both.", "The 32/30 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of L44649 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF L 44649/610 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in L44649 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (L44600-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single L44649 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does L44649 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load L44649 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit L44649?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 14.224 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is L44649 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "L44649-L44610", "equiv_brand": "NTN", "level": "partial", "note": "Same 26.988×50.292×14.224 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "L44649-610", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "L44649-610" ], "locale_variants": {} }, { "sku": "1982-1924A", "brand": "SKF", "manufacturer_designation": "SKF 1982/1924 A", "series": "1900-series", "type": "tapered_roller", "d_mm": 27.487, "D_mm": 57.159, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 55.6, "static_load_kN": 51, "fatigue_load_limit_kN": 5.6, "max_rpm": 12000, "reference_speed_rpm": 10000, "limiting_speed_rpm": 12000, "weight_g": 230, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (1900-series) ties the pair to a specific boundary plan. Dimensions 27.487×57.159×19.845 mm are the converted metric envelope. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 14.8 mm radial section height ((57.159−27.487)/2) and 230 g catalogue mass frame a 27.487 mm bore bearing rated at 55.6 kN C — roughly 2.02 kN of dynamic capacity per millimetre of bore before application factors. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 1982 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Speed envelope and thermal behaviour: at 10,000 r/min thermal reference, the 27.487 mm bore shaft runs at a dn of 275k, and the 14.8 mm section dissipates heat through the cup-to-housing contact path; the 12,000 r/min mechanical ceiling reflects cage strength, and the 230 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cup-side note for 1924 A: the outer ring's rib profile and the 57.159 mm outside diameter are cup-specific within the 1900-series tables, so substituting a different cup against the same 1982 cone changes both the assembled 19.845 mm width and the axial free-play setting of the mounted pair.SKF 1982/1924 A belongs to the SKF single-row tapered roller range — the 27.487 mm bore entry in the inch 1900-series, dimensioned 57.159 mm OD and 19.845 mm wide.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "On this 27.487 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 1982 pair heats, loses setting control and smears the roller-rib contact.", "The 1900-series inch series at 27.487 mm bore (57.159×19.845 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 1982 mounting error.", "At the 55.6 kN rating of 1982, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 12,000 r/min speed end and heavier preload only where moment stiffness dominates.", "Open 1982 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 55.6/51 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 1982 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 1982/1924 A designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 1982 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 1900-series code marks the dimensional series. The metric dimensions 27.487×57.159×19.845 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 1982 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (1900-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 1982 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 1982 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 1982 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 1982?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 19.845 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "1982-1924A", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1982-1924A" ], "locale_variants": {} }, { "sku": "1985-1922", "brand": "SKF", "manufacturer_designation": "SKF 1985/1922", "series": "1900-series", "type": "tapered_roller", "d_mm": 28.575, "D_mm": 57.15, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 58.2, "static_load_kN": 55, "fatigue_load_limit_kN": 6, "max_rpm": 12000, "reference_speed_rpm": 10000, "limiting_speed_rpm": 12000, "weight_g": 230, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 1985 (SKF 1985/1922) is the 1900-series tapered roller choice for a 28.575 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 57.15×19.845 mm envelope.The 1900-series series assigns 28.575 mm bore, 57.15 mm OD and 19.845 mm width to 1985; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. At 10,000 r/min reference speed the 14.3 mm-section 1985 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 12,000 r/min as the mechanical ceiling. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 1985 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Dimensional interchange map: within the 19800 series at 28.575 mm bore, the 57.15 mm OD and 19.845 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 14.3 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 230 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Cone-and-cup identity in 1985: the leading 1985 reference identifies the inner ring, rollers and cage; the trailing 1922 reference identifies the outer ring. The 1900-series series lists alternative cups for the same cone, each producing a different 57.15 mm OD or 19.845 mm width — hence a different SKU even though the bore stays at 28.575 mm.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 28.575 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 1985 pair heats, loses setting control and smears the roller-rib contact.", "The 1900-series inch series at 28.575 mm bore (57.15×19.845 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 58.2 kN rating of 1985, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 12,000 r/min speed end and heavier preload only where moment stiffness dominates.", "Setting is a design value, not an assembly feel: excessive preload in the 1985 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 57.15 mm cup race release as noise within the first running hours.", "The 58.2/55 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 1985 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 1985/1922 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 1985?", "a": "The SKF 1985/1922 is a single-row tapered roller bearing with 28.575 mm bore, 57.15 mm outer diameter and 19.845 mm width (1.125 × 2.25 × 0.781 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 58.2 kN, C0 55 kN, fatigue load limit Pu 6 kN, reference speed 10,000 r/min, limiting speed 12,000 r/min, mass about 230 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 1985 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 1900-series code marks the dimensional series. The metric dimensions 28.575×57.15×19.845 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 1985 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (1900-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 1985 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 1985 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 1985 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "1985-1930", "equiv_brand": "NTN", "level": "partial", "note": "Same 28.575×57.15×19.845 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "1985-1931", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "1985-1932", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "1985-1922", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1985-1922" ], "locale_variants": {} }, { "sku": "1988-1922", "brand": "SKF", "manufacturer_designation": "SKF 1988/1922", "series": "1900-series", "type": "tapered_roller", "d_mm": 28.575, "D_mm": 57.15, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 58.2, "static_load_kN": 55, "fatigue_load_limit_kN": 6, "max_rpm": 12000, "reference_speed_rpm": 10000, "limiting_speed_rpm": 12000, "weight_g": 230, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Catalogue mass 230 g for the 28.575×57.15×19.845 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. For a 28.575 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 1988 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Load system: the 58.2 kN basic dynamic rating C and 55 kN static rating C0 give a C0/C balance of 0.95, and dividing C by the 28.575 mm bore yields 2.04 kN per millimetre of journal — a density metric that compares across families; the 6 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 28.575 mm shaft carrying variable duty. Cone-and-cup identity in 1988: the leading 1988 reference identifies the inner ring, rollers and cage; the trailing 1922 reference identifies the outer ring. The 1900-series series lists alternative cups for the same cone, each producing a different 57.15 mm OD or 19.845 mm width — hence a different SKU even though the bore stays at 28.575 mm.For a 28.575 mm shaft carrying combined load, SKF lists 1988 under catalogue execution SKF 1988/1922: one open single-row tapered roller bearing in the inch 1900-series.In SKF inch-series tables 1988 sits at 28.575 mm bore (1.125 in) with a 57.15 mm cup OD and 19.845 mm total width — dimensions that trace back to the original Timken boundary plan for the 1900-series family. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "On this 28.575 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 1988 pair heats, loses setting control and smears the roller-rib contact.", "The 1900-series inch series at 28.575 mm bore (57.15×19.845 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 58.2 kN rating of 1988, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 12,000 r/min speed end and heavier preload only where moment stiffness dominates.", "Do not mix brands or executions inside one 1988 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 57.15 mm cup race release as noise within the first running hours.", "The 58.2/55 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 1988 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 1988/1922 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 1988 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 1988 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 1988 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 1988?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 19.845 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 1988 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 1988?", "a": "The SKF 1988/1922 is a single-row tapered roller bearing with 28.575 mm bore, 57.15 mm outer diameter and 19.845 mm width (1.125 × 2.25 × 0.781 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 58.2 kN, C0 55 kN, fatigue load limit Pu 6 kN, reference speed 10,000 r/min, limiting speed 12,000 r/min, mass about 230 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "1988-1922", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "1988-1922" ], "locale_variants": {} }, { "sku": "M86647-610", "brand": "SKF", "manufacturer_designation": "SKF M 86647/610", "series": "M86600-series", "type": "tapered_roller", "d_mm": 28.575, "D_mm": 64.292, "B_mm": 21.433, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 60.4, "static_load_kN": 61, "fatigue_load_limit_kN": 6.8, "max_rpm": 11000, "reference_speed_rpm": 8500, "limiting_speed_rpm": 11000, "weight_g": 350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The M86600-series series assigns 28.575 mm bore, 64.292 mm OD and 21.433 mm width to M86647; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 60.4 kN and C0 61 kN, the M86647 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 11,000 r/min. A single M86647 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Dimensional interchange map: within the M8600 series at 28.575 mm bore, the 64.292 mm OD and 21.433 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 17.9 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 350 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Cone versus cup responsibility in M86647: the M 86647 cone carries the 28.575 mm bore, rollers and pressed-steel cage; the 610 cup carries the 64.292 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.SKF M 86647/610 belongs to the SKF single-row tapered roller range — the 28.575 mm bore entry in the inch M86600-series, dimensioned 64.292 mm OD and 21.433 mm wide.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "machine-tool spindles" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "On this 28.575 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight M86647 pair heats, loses setting control and smears the roller-rib contact.", "The M86600-series inch series at 28.575 mm bore (64.292×21.433 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the M86647 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common M86647 mounting error.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 64.292 mm cup race release as noise within the first running hours.", "The 60.4/61 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of M86647 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF M 86647/610 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the M86647 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the M86600-series code marks the dimensional series. The metric dimensions 28.575×64.292×21.433 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in M86647 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (M86600-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single M86647 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does M86647 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load M86647 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit M86647?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 21.433 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "M86647-M86610", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "M86647-610", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "M86647-610" ], "locale_variants": {} }, { "sku": "L45449-410", "brand": "SKF", "manufacturer_designation": "SKF L 45449/410", "series": "L45400-series", "type": "tapered_roller", "d_mm": 29, "D_mm": 50.292, "B_mm": 14.224, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 31.8, "static_load_kN": 32.5, "fatigue_load_limit_kN": 3.35, "max_rpm": 13000, "reference_speed_rpm": 11000, "limiting_speed_rpm": 13000, "weight_g": 110, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Operating context for the 29 mm bore: a shaft of this diameter in the medium-bore band typically runs between 23200 and 34800 r/min in real machinery, and the 50.292 mm outside diameter places the housing shoulder at 58 mm outer abutment; the 14.224 mm width and 110 g mass together set the shaft critical speed and the housing resonance check for this L4500-series envelope. Cone versus cup responsibility in L45449: the L 45449 cone carries the 29 mm bore, rollers and pressed-steel cage; the 410 cup carries the 50.292 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.L45449 is a single-row tapered roller bearing in the L45400-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (L45400-series) ties the pair to a specific boundary plan. Dimensions 29×50.292×14.224 mm are the converted metric envelope. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Speed planning uses two different ceilings: 11,000 r/min thermal reference and 13,000 r/min mechanical limiting speed. A single L45449 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "On this 29 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight L45449 pair heats, loses setting control and smears the roller-rib contact.", "The L45400-series inch series at 29 mm bore (50.292×14.224 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the L45449 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Setting is a design value, not an assembly feel: excessive preload in the L45449 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 50.292 mm cup race release as noise within the first running hours.", "The 31.8/32.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of L45449 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF L 45449/410 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit L45449?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 14.224 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is L45449 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of L45449?", "a": "The SKF L 45449/410 is a single-row tapered roller bearing with 29 mm bore, 50.292 mm outer diameter and 14.224 mm width (1.142 × 1.98 × 0.56 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 31.8 kN, C0 32.5 kN, fatigue load limit Pu 3.35 kN, reference speed 11,000 r/min, limiting speed 13,000 r/min, mass about 110 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the L45449 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the L45400-series code marks the dimensional series. The metric dimensions 29×50.292×14.224 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in L45449 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (L45400-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "L45449-L45410", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "L45449-410", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "L45449-410" ], "locale_variants": {} }, { "sku": "M86649-610", "brand": "SKF", "manufacturer_designation": "SKF M 86649/610", "series": "M86600-series", "type": "tapered_roller", "d_mm": 30.162, "D_mm": 64.292, "B_mm": 21.433, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 60.4, "static_load_kN": 61, "fatigue_load_limit_kN": 6.8, "max_rpm": 11000, "reference_speed_rpm": 8500, "limiting_speed_rpm": 11000, "weight_g": 340, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Speed envelope and thermal behaviour: at 8,500 r/min thermal reference, the 30.162 mm bore shaft runs at a dn of 256k, and the 17.1 mm section dissipates heat through the cup-to-housing contact path; the 11,000 r/min mechanical ceiling reflects cage strength, and the 340 g spinning cone contributes gyroscopic moment under rapid speed reversal. From a specification standpoint the 610 cup is the controlling half of M86649 for housing design — it sets the 64.292 mm OD and the outer abutment diameter — while the M 86649 cone controls shaft fit at the 30.162 mm bore; the 21.433 mm width is the result of the two together.In SKF catalogue PUB BU/P1 17000, M86649 appears as SKF M 86649/610: an open, single-row tapered roller bearing in the M86600-series, supplied with a pressed-steel cage as standard.Numbering ties the bearing to its inch-series envelope: M86649 means a cone and cup matched pair in the M86600-series series — which is why the 30.162×64.292×21.433 mm outline swaps dimensionally with other inch-series bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Speed planning uses two different ceilings: 8,500 r/min thermal reference and 11,000 r/min mechanical limiting speed. Because the contact line is tapered, one M86649 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 30.162 mm shaft typically takes a k5 seat with an H7 housing bore.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "On this 30.162 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight M86649 pair heats, loses setting control and smears the roller-rib contact.", "The M86600-series inch series at 30.162 mm bore (64.292×21.433 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one M86649 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the M86649 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Catalogue reference speed and limiting speed are different limits: the 8,500 r/min reference is a thermal criterion under load, while the 11,000 r/min limiting value is the mechanical ceiling — observe both.", "The 60.4/61 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of M86649 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF M 86649/610 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit M86649?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 21.433 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is M86649 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of M86649?", "a": "The SKF M 86649/610 is a single-row tapered roller bearing with 30.162 mm bore, 64.292 mm outer diameter and 21.433 mm width (1.187 × 2.531 × 0.844 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 60.4 kN, C0 61 kN, fatigue load limit Pu 6.8 kN, reference speed 8,500 r/min, limiting speed 11,000 r/min, mass about 340 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the M86649 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the M86600-series code marks the dimensional series. The metric dimensions 30.162×64.292×21.433 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in M86649 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (M86600-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "M86649-M86610", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "M86649-610", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "M86649-610" ], "locale_variants": {} }, { "sku": "M88043-010", "brand": "SKF", "manufacturer_designation": "SKF M 88043/010", "series": "M88000-series", "type": "tapered_roller", "d_mm": 30.162, "D_mm": 68.262, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 67.1, "static_load_kN": 69.5, "fatigue_load_limit_kN": 7.8, "max_rpm": 10000, "reference_speed_rpm": 8000, "limiting_speed_rpm": 10000, "weight_g": 410, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Load system: the 67.1 kN basic dynamic rating C and 69.5 kN static rating C0 give a C0/C balance of 1.04, and dividing C by the 30.162 mm bore yields 2.22 kN per millimetre of journal — a density metric that compares across families; the 7.8 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 30.162 mm shaft carrying variable duty. The cup reference 010 is structural, not a suffix: it identifies the outer ring that, combined with the M 88043 cone, produces the 30.162/68.262/22.225 mm envelope catalogue-listed as M88043. Quote the cup number in full when ordering — the M88000-series tables contain other cups that fit the same cone but change the bearing.Ordering number SKF M 88043/010 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 30.162 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.The M88000-series series assigns 30.162 mm bore, 68.262 mm OD and 22.225 mm width to M88043; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. In SKF suffix language a bare M88043 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 7.8 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.04 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Specify pairs rather than single units wherever thrust reverses: the tapered contact of M88043 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "On this 30.162 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight M88043 pair heats, loses setting control and smears the roller-rib contact.", "The M88000-series inch series at 30.162 mm bore (68.262×22.225 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single M88043 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Do not mix brands or executions inside one M88043 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 67.1/69.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of M88043 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF M 88043/010 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit M88043?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 22.225 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is M88043 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of M88043?", "a": "The SKF M 88043/010 is a single-row tapered roller bearing with 30.162 mm bore, 68.262 mm outer diameter and 22.225 mm width (1.187 × 2.687 × 0.875 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 67.1 kN, C0 69.5 kN, fatigue load limit Pu 7.8 kN, reference speed 8,000 r/min, limiting speed 10,000 r/min, mass about 410 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the M88043 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the M88000-series code marks the dimensional series. The metric dimensions 30.162×68.262×22.225 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in M88043 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (M88000-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "M88043-010", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "M88043-010" ], "locale_variants": {} }, { "sku": "LM67048-010", "brand": "SKF", "manufacturer_designation": "SKF LM 67048/010", "series": "LM67000-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 59.131, "B_mm": 15.875, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 42.8, "static_load_kN": 41.5, "fatigue_load_limit_kN": 4.4, "max_rpm": 11000, "reference_speed_rpm": 9500, "limiting_speed_rpm": 11000, "weight_g": 180, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Two catalogue entries share the LM 67048 cone but use different cups; this one, LM67048, takes the 010 cup and is ground for the resulting 59.131 mm OD / 15.875 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.LM67048 is a single-row tapered roller bearing in the LM67000-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.In SKF inch-series tables LM67048 sits at 31.75 mm bore (1.25 in) with a 59.131 mm cup OD and 15.875 mm total width — dimensions that trace back to the original Timken boundary plan for the LM67000-series family. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 42.8 kN and C0 41.5 kN, the LM67048 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 11,000 r/min. Fit selection follows the rotating ring — interference on a rotating cone — and two LM67048 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Speed envelope and thermal behaviour: at 9,500 r/min thermal reference, the 31.75 mm bore shaft runs at a dn of 302k, and the 13.7 mm section dissipates heat through the cup-to-housing contact path; the 11,000 r/min mechanical ceiling reflects cage strength, and the 180 g spinning cone contributes gyroscopic moment under rapid speed reversal.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "On this 31.75 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM67048 pair heats, loses setting control and smears the roller-rib contact.", "The LM67000-series inch series at 31.75 mm bore (59.131×15.875 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the LM67048 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of LM67048 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The LM67048 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 42.8/41.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM67048 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 67048/010 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is LM67048 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM67048?", "a": "The SKF LM 67048/010 is a single-row tapered roller bearing with 31.75 mm bore, 59.131 mm outer diameter and 15.875 mm width (1.25 × 2.328 × 0.625 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 42.8 kN, C0 41.5 kN, fatigue load limit Pu 4.4 kN, reference speed 9,500 r/min, limiting speed 11,000 r/min, mass about 180 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM67048 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM67000-series code marks the dimensional series. The metric dimensions 31.75×59.131×15.875 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM67048 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM67000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM67048 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "LM67048-LM67010", "equiv_brand": "NTN", "level": "partial", "note": "Same 31.75×59.131×15.875 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "LM67048-010", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM67048-010" ], "locale_variants": {} }, { "sku": "15123-15243", "brand": "SKF", "manufacturer_designation": "SKF 15123/15243", "series": "15000-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 61.912, "B_mm": 18.161, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 59.5, "static_load_kN": 57, "fatigue_load_limit_kN": 6.2, "max_rpm": 11000, "reference_speed_rpm": 9000, "limiting_speed_rpm": 11000, "weight_g": 240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 31.75 mm shaft carrying combined load, SKF lists 15123 under catalogue execution SKF 15123/15243: one open single-row tapered roller bearing in the inch 15000-series.In SKF inch-series tables 15123 sits at 31.75 mm bore (1.25 in) with a 61.912 mm cup OD and 18.161 mm total width — dimensions that trace back to the original Timken boundary plan for the 15000-series family. In SKF suffix language a bare 15123 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 0.96 (static 57 kN against dynamic 59.5 kN), typical of a tapered roller sized for axial capacity, and the 6.2 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Mounting practice for 15123: the rotating cone takes the interference fit (k5 on a 31.75 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Journal and housing interface: the 31.75 mm bore takes a k5 shaft seat (upper deviation ~0.064 mm for this diameter range) and the 61.912 mm outside diameter pairs with an H7 housing bore tolerance band of 61.912.000/61.932 mm; the 18.161 mm width defines the shoulder depth, and the 240 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Within the 15000-series tables, 15123 appears in several rows because SKF lists multiple cup options for the same cone. 15123 is the 15243 variant, with 61.912 mm OD and 18.161 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 31.75 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 15123 pair heats, loses setting control and smears the roller-rib contact.", "The 15000-series inch series at 31.75 mm bore (61.912×18.161 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one 15123 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "A single 15123 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Shaft and housing fillets must clear the bearing chamfer so the 18.161 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 59.5/57 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 15123 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 15123/15243 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 15123?", "a": "The SKF 15123/15243 is a single-row tapered roller bearing with 31.75 mm bore, 61.912 mm outer diameter and 18.161 mm width (1.25 × 2.437 × 0.715 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 59.5 kN, C0 57 kN, fatigue load limit Pu 6.2 kN, reference speed 9,000 r/min, limiting speed 11,000 r/min, mass about 240 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 15123 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 15000-series code marks the dimensional series. The metric dimensions 31.75×61.912×18.161 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 15123 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (15000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 15123 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 15123 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 15123 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "15123-15245-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 31.75×61.912×18.161 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "15123-15243", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "15123-15243" ], "locale_variants": {} }, { "sku": "15123-15245", "brand": "SKF", "manufacturer_designation": "SKF 15123/15245", "series": "15000-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 62, "B_mm": 18.161, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 59.5, "static_load_kN": 57, "fatigue_load_limit_kN": 6.2, "max_rpm": 11000, "reference_speed_rpm": 9000, "limiting_speed_rpm": 11000, "weight_g": 240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " At 9,000 r/min reference speed the 15.1 mm-section 15123 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 11,000 r/min as the mechanical ceiling. For a 31.75 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 15123 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Material and manufacturing detail: the 240 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 15100 ISO envelope, with the pressed-steel cage contributing roughly 7 g of the total; the 31.75 mm bore is ground to IT5 roundness and the 62 mm OD to IT5 cylindricity, and the 18.161 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Why the cup reference matters here: in the 15000-series tables the 15123 cone appears against several cup options. 15123 is the pairing with 15245, and that choice — not the cone — fixes the 62 mm OD, the raceway track position and the 18.161 mm assembled width.15123 is a single-row tapered roller bearing in the 15000-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.On the SKF nameplate, 15123 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 15000-series marking the dimensional series. In SKF suffix language a bare 15123 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 31.75 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 15123 pair heats, loses setting control and smears the roller-rib contact.", "The 15000-series inch series at 31.75 mm bore (62×18.161 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 15123 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "At the 59.5 kN rating of 15123, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 11,000 r/min speed end and heavier preload only where moment stiffness dominates.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 59.5/57 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 15123 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 15123/15245 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 15123 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 15123 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 15123 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 15123?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 18.161 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 15123 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 15123?", "a": "The SKF 15123/15245 is a single-row tapered roller bearing with 31.75 mm bore, 62 mm outer diameter and 18.161 mm width (1.25 × 2.441 × 0.715 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 59.5 kN, C0 57 kN, fatigue load limit Pu 6.2 kN, reference speed 9,000 r/min, limiting speed 11,000 r/min, mass about 240 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "15123-15245-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 31.75×62×18.161 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "15123-15245", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "15123-15245" ], "locale_variants": {} }, { "sku": "HM88542-510", "brand": "SKF", "manufacturer_designation": "SKF HM 88542/510", "series": "HM88500-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 73.025, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 86.5, "static_load_kN": 95, "fatigue_load_limit_kN": 10.4, "max_rpm": 9000, "reference_speed_rpm": 7500, "limiting_speed_rpm": 9000, "weight_g": 620, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Cross-section geometry: the 20.6 mm half-section ((73.025−31.75)/2) of this HM800-series unit places the roller large-end pitch diameter at roughly 52 mm, and the 29.37 mm axial width is split between cone (16 mm) and cup rib (13 mm) — a geometry that sets the contact angle and, with the 620 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Why the cup reference matters here: in the HM88500-series tables the HM 88542 cone appears against several cup options. HM88542 is the pairing with 510, and that choice — not the cone — fixes the 73.025 mm OD, the raceway track position and the 29.37 mm assembled width.The SKF HM 88542/510 is a 31.75×73.025×29.37 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (HM88500-series) ties the pair to a specific boundary plan. Dimensions 31.75×73.025×29.37 mm are the converted metric envelope. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 10.4 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.10 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. For a 31.75 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two HM88542 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "On this 31.75 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight HM88542 pair heats, loses setting control and smears the roller-rib contact.", "The HM88500-series inch series at 31.75 mm bore (73.025×29.37 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the HM88542 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the HM88542 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Open HM88542 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 86.5/95 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM88542 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 88542/510 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit HM88542?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 29.37 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HM88542 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM88542?", "a": "The SKF HM 88542/510 is a single-row tapered roller bearing with 31.75 mm bore, 73.025 mm outer diameter and 29.37 mm width (1.25 × 2.875 × 1.156 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 86.5 kN, C0 95 kN, fatigue load limit Pu 10.4 kN, reference speed 7,500 r/min, limiting speed 9,000 r/min, mass about 620 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM88542 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM88500-series code marks the dimensional series. The metric dimensions 31.75×73.025×29.37 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM88542 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM88500-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "HM88542-HM88510", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "HM88542-HM88512", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "HM88542-510", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM88542-510" ], "locale_variants": {} }, { "sku": "M88048-010", "brand": "SKF", "manufacturer_designation": "SKF M 88048/010", "series": "M88000-series", "type": "tapered_roller", "d_mm": 33.338, "D_mm": 68.262, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 67.1, "static_load_kN": 69.5, "fatigue_load_limit_kN": 7.8, "max_rpm": 10000, "reference_speed_rpm": 8000, "limiting_speed_rpm": 10000, "weight_g": 380, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Reading the designation: M88048 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the M88000-series code identifies the dimensional series. The 33.338 mm bore, 68.262 mm OD and 22.225 mm width are the metric equivalents of the inch boundary dimensions. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Selection arithmetic: the C0/C ratio is about 1.04 (static 69.5 kN against dynamic 67.1 kN), typical of a tapered roller sized for axial capacity, and the 7.8 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Fit selection follows the rotating ring — interference on a rotating cone — and two M88048 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Load system: the 67.1 kN basic dynamic rating C and 69.5 kN static rating C0 give a C0/C balance of 1.04, and dividing C by the 33.338 mm bore yields 2.01 kN per millimetre of journal — a density metric that compares across families; the 7.8 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 33.338 mm shaft carrying variable duty. Why the cup reference matters here: in the M88000-series tables the M 88048 cone appears against several cup options. M88048 is the pairing with 010, and that choice — not the cone — fixes the 68.262 mm OD, the raceway track position and the 22.225 mm assembled width.M88048 is a single-row tapered roller bearing in the M88000-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "On this 33.338 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight M88048 pair heats, loses setting control and smears the roller-rib contact.", "The M88000-series inch series at 33.338 mm bore (68.262×22.225 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of M88048 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of M88048 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Open M88048 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 67.1/69.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of M88048 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF M 88048/010 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the M88048 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the M88000-series code marks the dimensional series. The metric dimensions 33.338×68.262×22.225 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in M88048 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (M88000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single M88048 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does M88048 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load M88048 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit M88048?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 22.225 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "M88048-M88010", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "M88048-010", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "M88048-010" ], "locale_variants": {} }, { "sku": "14131-14276", "brand": "SKF", "manufacturer_designation": "SKF 14131/14276", "series": "14000-series", "type": "tapered_roller", "d_mm": 33.338, "D_mm": 69.012, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 65.8, "static_load_kN": 67, "fatigue_load_limit_kN": 7.35, "max_rpm": 10000, "reference_speed_rpm": 8000, "limiting_speed_rpm": 10000, "weight_g": 350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "14131 is a single-row tapered roller bearing in the 14000-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Digit by digit, 14131 reads as cone reference / cup reference in the 14000-series inch series; the 33.338 mm bore, 69.012 mm OD and 19.845 mm width are the metric equivalents of the original inch boundary values. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 7.35 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.02 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Mounting practice for 14131: the rotating cone takes the interference fit (k5 on a 33.338 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Load system: the 65.8 kN basic dynamic rating C and 67 kN static rating C0 give a C0/C balance of 1.02, and dividing C by the 33.338 mm bore yields 1.97 kN per millimetre of journal — a density metric that compares across families; the 7.35 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 33.338 mm shaft carrying variable duty. Cone versus cup responsibility in 14131: the 14131 cone carries the 33.338 mm bore, rollers and pressed-steel cage; the 14276 cup carries the 69.012 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "belt-driven fan and blower shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "On this 33.338 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 14131 pair heats, loses setting control and smears the roller-rib contact.", "The 14000-series inch series at 33.338 mm bore (69.012×19.845 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 14131 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 14131 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Catalogue reference speed and limiting speed are different limits: the 8,000 r/min reference is a thermal criterion under load, while the 10,000 r/min limiting value is the mechanical ceiling — observe both.", "The 65.8/67 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 14131 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 14131/14276 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 14131?", "a": "The SKF 14131/14276 is a single-row tapered roller bearing with 33.338 mm bore, 69.012 mm outer diameter and 19.845 mm width (1.313 × 2.717 × 0.781 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 65.8 kN, C0 67 kN, fatigue load limit Pu 7.35 kN, reference speed 8,000 r/min, limiting speed 10,000 r/min, mass about 350 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 14131 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 14000-series code marks the dimensional series. The metric dimensions 33.338×69.012×19.845 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 14131 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (14000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 14131 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 14131 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 14131 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "14131-14276", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "14131-14276" ], "locale_variants": {} }, { "sku": "LM48548-510", "brand": "SKF", "manufacturer_designation": "SKF LM 48548/510", "series": "LM48500-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 65.088, "B_mm": 18.034, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 58, "static_load_kN": 57, "fatigue_load_limit_kN": 6.2, "max_rpm": 10000, "reference_speed_rpm": 8500, "limiting_speed_rpm": 10000, "weight_g": 250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Mounting practice for LM48548: the rotating cone takes the interference fit (k5 on a 34.925 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Material and manufacturing detail: the 250 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the LM400 ISO envelope, with the pressed-steel cage contributing roughly 8 g of the total; the 34.925 mm bore is ground to IT5 roundness and the 65.088 mm OD to IT5 cylindricity, and the 18.034 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Cone-and-cup identity in LM48548: the leading LM 48548 reference identifies the inner ring, rollers and cage; the trailing 510 reference identifies the outer ring. The LM48500-series series lists alternative cups for the same cone, each producing a different 65.088 mm OD or 18.034 mm width — hence a different SKU even though the bore stays at 34.925 mm.Ordering number SKF LM 48548/510 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 34.925 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.Reading the designation: LM48548 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the LM48500-series code identifies the dimensional series. The 34.925 mm bore, 65.088 mm OD and 18.034 mm width are the metric equivalents of the inch boundary dimensions. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. At 8,500 r/min reference speed the 15.1 mm-section LM48548 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 10,000 r/min as the mechanical ceiling.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "On this 34.925 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM48548 pair heats, loses setting control and smears the roller-rib contact.", "The LM48500-series inch series at 34.925 mm bore (65.088×18.034 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single LM48548 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "At the 58 kN rating of LM48548, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 10,000 r/min speed end and heavier preload only where moment stiffness dominates.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 58/57 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM48548 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 48548/510 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does LM48548 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM48548 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM48548?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 18.034 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM48548 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM48548?", "a": "The SKF LM 48548/510 is a single-row tapered roller bearing with 34.925 mm bore, 65.088 mm outer diameter and 18.034 mm width (1.375 × 2.563 × 0.71 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 58 kN, C0 57 kN, fatigue load limit Pu 6.2 kN, reference speed 8,500 r/min, limiting speed 10,000 r/min, mass about 250 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM48548 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM48500-series code marks the dimensional series. The metric dimensions 34.925×65.088×18.034 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "LM48548-LM48510", "equiv_brand": "NTN", "level": "partial", "note": "Same 34.925×65.088×18.034 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "LM48548-510", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM48548-510" ], "locale_variants": {} }, { "sku": "LM48548A-510", "brand": "SKF", "manufacturer_designation": "SKF LM 48548 A/510", "series": "LM48500-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 65.088, "B_mm": 18.034, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 58, "static_load_kN": 57, "fatigue_load_limit_kN": 6.2, "max_rpm": 10000, "reference_speed_rpm": 8500, "limiting_speed_rpm": 10000, "weight_g": 260, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Speed planning uses two different ceilings: 8,500 r/min thermal reference and 10,000 r/min mechanical limiting speed. A single LM48548A locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Material and manufacturing detail: the 260 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the LM400 ISO envelope, with the pressed-steel cage contributing roughly 8 g of the total; the 34.925 mm bore is ground to IT5 roundness and the 65.088 mm OD to IT5 cylindricity, and the 18.034 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Why the cup reference matters here: in the LM48500-series tables the LM 48548 A cone appears against several cup options. LM48548A is the pairing with 510, and that choice — not the cone — fixes the 65.088 mm OD, the raceway track position and the 18.034 mm assembled width.LM48548A is a single-row tapered roller bearing in the LM48500-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Reading the designation: LM48548A follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the LM48500-series code identifies the dimensional series. The 34.925 mm bore, 65.088 mm OD and 18.034 mm width are the metric equivalents of the inch boundary dimensions.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "On this 34.925 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM48548A pair heats, loses setting control and smears the roller-rib contact.", "The LM48500-series inch series at 34.925 mm bore (65.088×18.034 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the LM48548A pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Setting is a design value, not an assembly feel: excessive preload in the LM48548A pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 58/57 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM48548A (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 48548 A/510 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in LM48548A mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM48500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM48548A take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM48548A compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM48548A position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM48548A?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 18.034 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM48548A interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "LM48548A-LM48510", "equiv_brand": "NTN", "level": "partial", "note": "Same 34.925×65.088×18.034 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "LM48548A-510", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM48548A-510" ], "locale_variants": {} }, { "sku": "14137A-14276", "brand": "SKF", "manufacturer_designation": "SKF 14137 A/14276", "series": "14000-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 69.012, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 65.8, "static_load_kN": 67, "fatigue_load_limit_kN": 7.35, "max_rpm": 10000, "reference_speed_rpm": 8000, "limiting_speed_rpm": 10000, "weight_g": 340, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 340 g for the 34.925×69.012×19.845 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. For a 34.925 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 14137A bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Load system: the 65.8 kN basic dynamic rating C and 67 kN static rating C0 give a C0/C balance of 1.02, and dividing C by the 34.925 mm bore yields 1.88 kN per millimetre of journal — a density metric that compares across families; the 7.35 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 34.925 mm shaft carrying variable duty. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 14137A the 14137 A cone contributes the 34.925 mm bore and roller set, the 14276 cup contributes the 69.012 mm OD raceway, and the assembled 19.845 mm width is the catalogue value.SKF 14137 A/14276 belongs to the SKF single-row tapered roller range — the 34.925 mm bore entry in the inch 14000-series, dimensioned 69.012 mm OD and 19.845 mm wide.On the SKF nameplate, 14137A denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 14000-series marking the dimensional series.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "On this 34.925 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 14137A pair heats, loses setting control and smears the roller-rib contact.", "The 14000-series inch series at 34.925 mm bore (69.012×19.845 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one 14137A pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Setting is a design value, not an assembly feel: excessive preload in the 14137A pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 69.012 mm cup race release as noise within the first running hours.", "The 65.8/67 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 14137A (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 14137 A/14276 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in 14137A mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (14000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 14137A take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 14137A compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 14137A position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 14137A?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 19.845 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 14137A interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "14137A-14276-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 34.925×69.012×19.845 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "14137A-14276", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "14137A-14276" ], "locale_variants": {} }, { "sku": "HM88649X-610", "brand": "SKF", "manufacturer_designation": "SKF HM 88649 X/610", "series": "HM88600-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 72.233, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 83, "static_load_kN": 90, "fatigue_load_limit_kN": 10, "max_rpm": 9000, "reference_speed_rpm": 7500, "limiting_speed_rpm": 9000, "weight_g": 500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Reading the designation: HM88649X follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the HM88600-series code identifies the dimensional series. The 34.925 mm bore, 72.233 mm OD and 25.4 mm width are the metric equivalents of the inch boundary dimensions. In SKF suffix language a bare HM88649X is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 1.08 (static 90 kN against dynamic 83 kN), typical of a tapered roller sized for axial capacity, and the 10 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. A single HM88649X locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Material and manufacturing detail: the 500 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the HM800 ISO envelope, with the pressed-steel cage contributing roughly 15 g of the total; the 34.925 mm bore is ground to IT5 roundness and the 72.233 mm OD to IT5 cylindricity, and the 25.4 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Cup-side note for 610: the outer ring's rib profile and the 72.233 mm outside diameter are cup-specific within the HM88600-series tables, so substituting a different cup against the same HM 88649 X cone changes both the assembled 25.4 mm width and the axial free-play setting of the mounted pair.Ordering number SKF HM 88649 X/610 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 34.925 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 34.925 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight HM88649X pair heats, loses setting control and smears the roller-rib contact.", "The HM88600-series inch series at 34.925 mm bore (72.233×25.4 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HM88649X pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HM88649X pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 83/90 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM88649X (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 88649 X/610 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the HM88649X inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM88600-series code marks the dimensional series. The metric dimensions 34.925×72.233×25.4 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM88649X mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM88600-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single HM88649X take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HM88649X compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM88649X position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HM88649X?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 25.4 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "HM88649X-610", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM88649X-610" ], "locale_variants": {} }, { "sku": "HM88649-610", "brand": "SKF", "manufacturer_designation": "SKF HM 88649/610", "series": "HM88600-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 72.233, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 83, "static_load_kN": 90, "fatigue_load_limit_kN": 10, "max_rpm": 9000, "reference_speed_rpm": 7500, "limiting_speed_rpm": 9000, "weight_g": 500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Material and manufacturing detail: the 500 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the HM800 ISO envelope, with the pressed-steel cage contributing roughly 15 g of the total; the 34.925 mm bore is ground to IT5 roundness and the 72.233 mm OD to IT5 cylindricity, and the 25.4 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Within the HM88600-series tables, HM 88649 appears in several rows because SKF lists multiple cup options for the same cone. HM88649 is the 610 variant, with 72.233 mm OD and 25.4 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.SKF HM 88649/610 belongs to the SKF single-row tapered roller range — the 34.925 mm bore entry in the inch HM88600-series, dimensioned 72.233 mm OD and 25.4 mm wide.Numbering ties the bearing to its inch-series envelope: HM88649 means a cone and cup matched pair in the HM88600-series series — which is why the 34.925×72.233×25.4 mm outline swaps dimensionally with other inch-series bearings of the same code. In SKF suffix language a bare HM88649 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Catalogue mass 500 g for the 34.925×72.233×25.4 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. For a 34.925 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two HM88649 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "On this 34.925 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight HM88649 pair heats, loses setting control and smears the roller-rib contact.", "The HM88600-series inch series at 34.925 mm bore (72.233×25.4 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one HM88649 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Setting is a design value, not an assembly feel: excessive preload in the HM88649 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The HM88649 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 83/90 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM88649 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 88649/610 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit HM88649?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 25.4 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HM88649 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM88649?", "a": "The SKF HM 88649/610 is a single-row tapered roller bearing with 34.925 mm bore, 72.233 mm outer diameter and 25.4 mm width (1.375 × 2.844 × 1 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 83 kN, C0 90 kN, fatigue load limit Pu 10 kN, reference speed 7,500 r/min, limiting speed 9,000 r/min, mass about 500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM88649 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM88600-series code marks the dimensional series. The metric dimensions 34.925×72.233×25.4 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM88649 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM88600-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "HM88649-HM88610", "equiv_brand": "NTN", "level": "partial", "note": "Same 34.925×72.233×25.4 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "HM88649-610", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM88649-610" ], "locale_variants": {} }, { "sku": "25877-25821", "brand": "SKF", "manufacturer_designation": "SKF 25877/25821", "series": "25800-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 73.025, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 89.1, "static_load_kN": 88, "fatigue_load_limit_kN": 9.8, "max_rpm": 9500, "reference_speed_rpm": 8000, "limiting_speed_rpm": 9500, "weight_g": 480, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Dimensional interchange map: within the 25800 series at 34.925 mm bore, the 73.025 mm OD and 23.812 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 19.1 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 480 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Why the cup reference matters here: in the 25800-series tables the 25877 cone appears against several cup options. 25877 is the pairing with 25821, and that choice — not the cone — fixes the 73.025 mm OD, the raceway track position and the 23.812 mm assembled width.The SKF 25877/25821 is a 34.925×73.025×23.812 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.In SKF inch-series tables 25877 sits at 34.925 mm bore (1.375 in) with a 73.025 mm cup OD and 23.812 mm total width — dimensions that trace back to the original Timken boundary plan for the 25800-series family. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Selection arithmetic: the C0/C ratio is about 0.99 (static 88 kN against dynamic 89.1 kN), typical of a tapered roller sized for axial capacity, and the 9.8 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Mounting practice for 25877: the rotating cone takes the interference fit (k5 on a 34.925 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "On this 34.925 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 25877 pair heats, loses setting control and smears the roller-rib contact.", "The 25800-series inch series at 34.925 mm bore (73.025×23.812 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 25877 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 25877 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The 25877 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 89.1/88 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 25877 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 25877/25821 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 25877?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 23.812 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 25877 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 25877?", "a": "The SKF 25877/25821 is a single-row tapered roller bearing with 34.925 mm bore, 73.025 mm outer diameter and 23.812 mm width (1.375 × 2.875 × 0.937 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 89.1 kN, C0 88 kN, fatigue load limit Pu 9.8 kN, reference speed 8,000 r/min, limiting speed 9,500 r/min, mass about 480 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 25877 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 25800-series code marks the dimensional series. The metric dimensions 34.925×73.025×23.812 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 25877 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (25800-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "25877-25820", "equiv_brand": "NTN", "level": "partial", "note": "Same 34.925×73.025×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25877-25821-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 34.925×73.025×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25877-25821", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "25877-25821" ], "locale_variants": {} }, { "sku": "23690-23620", "brand": "SKF", "manufacturer_designation": "SKF 23690/23620", "series": "23600-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 73.025, "B_mm": 26.988, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 94.6, "static_load_kN": 93, "fatigue_load_limit_kN": 10.4, "max_rpm": 9500, "reference_speed_rpm": 8000, "limiting_speed_rpm": 9500, "weight_g": 530, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Numbering ties the bearing to its inch-series envelope: 23690 means a cone and cup matched pair in the 23600-series series — which is why the 34.925×73.025×26.988 mm outline swaps dimensionally with other inch-series bearings of the same code. In SKF suffix language a bare 23690 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 10.4 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 0.98 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 23690 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Operating context for the 34.925 mm bore: a shaft of this diameter in the medium-bore band typically runs between 27940 and 41910 r/min in real machinery, and the 73.025 mm outside diameter places the housing shoulder at 81 mm outer abutment; the 26.988 mm width and 530 g mass together set the shaft critical speed and the housing resonance check for this 23600-series envelope. Inch tapered bearings are matched sets, not mix-and-match components: 23690 pairs the 23690 cone with the 23620 cup under the 23600-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.SKF 23690/23620 belongs to the SKF single-row tapered roller range — the 34.925 mm bore entry in the inch 23600-series, dimensioned 73.025 mm OD and 26.988 mm wide.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "On this 34.925 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 23690 pair heats, loses setting control and smears the roller-rib contact.", "The 23600-series inch series at 34.925 mm bore (73.025×26.988 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 94.6 kN rating of 23690, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 9,500 r/min speed end and heavier preload only where moment stiffness dominates.", "At the 94.6 kN rating of 23690, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 9,500 r/min speed end and heavier preload only where moment stiffness dominates.", "Open 23690 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 94.6/93 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 23690 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 23690/23620 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 23690 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 23600-series code marks the dimensional series. The metric dimensions 34.925×73.025×26.988 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 23690 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (23600-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 23690 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 23690 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 23690 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 23690?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 26.988 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "23690-23620", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "23690-23620" ], "locale_variants": {} }, { "sku": "HM89446-410", "brand": "SKF", "manufacturer_designation": "SKF HM 89446/410", "series": "HM89400-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 76.2, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 95.2, "static_load_kN": 106, "fatigue_load_limit_kN": 11.8, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500, "weight_g": 660, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Fit selection follows the rotating ring — interference on a rotating cone — and two HM89446 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Dimensional interchange map: within the HM800 series at 34.925 mm bore, the 76.2 mm OD and 29.37 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 20.6 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 660 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Why the cup reference matters here: in the HM89400-series tables the HM 89446 cone appears against several cup options. HM89446 is the pairing with 410, and that choice — not the cone — fixes the 76.2 mm OD, the raceway track position and the 29.37 mm assembled width.HM89446 is a single-row tapered roller bearing in the HM89400-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.The HM89400-series series assigns 34.925 mm bore, 76.2 mm OD and 29.37 mm width to HM89446; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. In SKF suffix language a bare HM89446 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 7,000 r/min reference speed the 20.6 mm-section HM89446 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 8,500 r/min as the mechanical ceiling.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "On this 34.925 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight HM89446 pair heats, loses setting control and smears the roller-rib contact.", "The HM89400-series inch series at 34.925 mm bore (76.2×29.37 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one HM89446 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HM89446 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The 660 g mass and 29.37 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of HM89446.", "The 95.2/106 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM89446 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 89446/410 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does HM89446 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM89446 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HM89446?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 29.37 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HM89446 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM89446?", "a": "The SKF HM 89446/410 is a single-row tapered roller bearing with 34.925 mm bore, 76.2 mm outer diameter and 29.37 mm width (1.375 × 3 × 1.156 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 95.2 kN, C0 106 kN, fatigue load limit Pu 11.8 kN, reference speed 7,000 r/min, limiting speed 8,500 r/min, mass about 660 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM89446 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM89400-series code marks the dimensional series. The metric dimensions 34.925×76.2×29.37 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "HM89446-HM89410", "equiv_brand": "NTN", "level": "partial", "note": "Same 34.925×76.2×29.37 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "HM89446-410", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM89446-410" ], "locale_variants": {} }, { "sku": "L68149-110", "brand": "SKF", "manufacturer_designation": "SKF L 68149/110", "series": "L68100-series", "type": "tapered_roller", "d_mm": 34.987, "D_mm": 59.131, "B_mm": 15.875, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 40.6, "static_load_kN": 44, "fatigue_load_limit_kN": 4.5, "max_rpm": 11000, "reference_speed_rpm": 9000, "limiting_speed_rpm": 11000, "weight_g": 170, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Catalogue mass 170 g for the 34.987×59.131×15.875 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Specify pairs rather than single units wherever thrust reverses: the tapered contact of L68149 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Dimensional interchange map: within the L6800 series at 34.987 mm bore, the 59.131 mm OD and 15.875 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 12.1 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 170 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in L68149 the L 68149 cone contributes the 34.987 mm bore and roller set, the 110 cup contributes the 59.131 mm OD raceway, and the assembled 15.875 mm width is the catalogue value.L68149 is a single-row tapered roller bearing in the L68100-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.The L68100-series series assigns 34.987 mm bore, 59.131 mm OD and 15.875 mm width to L68149; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. In SKF suffix language a bare L68149 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 34.987 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight L68149 pair heats, loses setting control and smears the roller-rib contact.", "The L68100-series inch series at 34.987 mm bore (59.131×15.875 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the L68149 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "A single L68149 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The 170 g mass and 15.875 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of L68149.", "The 40.6/44 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of L68149 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF L 68149/110 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single L68149 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does L68149 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load L68149 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit L68149?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 15.875 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is L68149 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of L68149?", "a": "The SKF L 68149/110 is a single-row tapered roller bearing with 34.987 mm bore, 59.131 mm outer diameter and 15.875 mm width (1.377 × 2.328 × 0.625 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 40.6 kN, C0 44 kN, fatigue load limit Pu 4.5 kN, reference speed 9,000 r/min, limiting speed 11,000 r/min, mass about 170 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "L68149-L68111", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "L68149-110", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "L68149-110" ], "locale_variants": {} }, { "sku": "L68149-111", "brand": "SKF", "manufacturer_designation": "SKF L 68149/111", "series": "L68100-series", "type": "tapered_roller", "d_mm": 34.987, "D_mm": 59.975, "B_mm": 15.875, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 40.6, "static_load_kN": 44, "fatigue_load_limit_kN": 4.5, "max_rpm": 11000, "reference_speed_rpm": 9000, "limiting_speed_rpm": 11000, "weight_g": 180, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Numbering ties the bearing to its inch-series envelope: L68149 means a cone and cup matched pair in the L68100-series series — which is why the 34.987×59.975×15.875 mm outline swaps dimensionally with other inch-series bearings of the same code. In SKF suffix language a bare L68149 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 1.08 (static 44 kN against dynamic 40.6 kN), typical of a tapered roller sized for axial capacity, and the 4.5 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Mounting practice for L68149: the rotating cone takes the interference fit (k5 on a 34.987 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Load system: the 40.6 kN basic dynamic rating C and 44 kN static rating C0 give a C0/C balance of 1.08, and dividing C by the 34.987 mm bore yields 1.16 kN per millimetre of journal — a density metric that compares across families; the 4.5 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 34.987 mm shaft carrying variable duty. Why the cup reference matters here: in the L68100-series tables the L 68149 cone appears against several cup options. L68149 is the pairing with 111, and that choice — not the cone — fixes the 59.975 mm OD, the raceway track position and the 15.875 mm assembled width.SKF L68149 (SKF L 68149/111) is the L68100-series tapered roller choice for a 34.987 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 59.975×15.875 mm envelope.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 34.987 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight L68149 pair heats, loses setting control and smears the roller-rib contact.", "The L68100-series inch series at 34.987 mm bore (59.975×15.875 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 40.6 kN rating of L68149, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 11,000 r/min speed end and heavier preload only where moment stiffness dominates.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common L68149 mounting error.", "Shaft and housing fillets must clear the bearing chamfer so the 15.875 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 40.6/44 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of L68149 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF L 68149/111 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the L68149 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the L68100-series code marks the dimensional series. The metric dimensions 34.987×59.975×15.875 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in L68149 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (L68100-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single L68149 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does L68149 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load L68149 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit L68149?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 15.875 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "L68149-L68111", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "L68149-111", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "L68149-111" ], "locale_variants": {} }, { "sku": "HM88648-610", "brand": "SKF", "manufacturer_designation": "SKF HM 88648/610", "series": "HM88600-series", "type": "tapered_roller", "d_mm": 35.717, "D_mm": 72.233, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 83, "static_load_kN": 90, "fatigue_load_limit_kN": 10, "max_rpm": 9000, "reference_speed_rpm": 7500, "limiting_speed_rpm": 9000, "weight_g": 490, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The 10 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.08 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Fit selection follows the rotating ring — interference on a rotating cone — and two HM88648 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Cross-section geometry: the 18.3 mm half-section ((72.233−35.717)/2) of this HM800-series unit places the roller large-end pitch diameter at roughly 53 mm, and the 25.4 mm axial width is split between cone (14 mm) and cup rib (11 mm) — a geometry that sets the contact angle and, with the 490 g rotating cone mass, the critical speed at which cage-roller imbalance begins. From a specification standpoint the 610 cup is the controlling half of HM88648 for housing design — it sets the 72.233 mm OD and the outer abutment diameter — while the HM 88648 cone controls shaft fit at the 35.717 mm bore; the 25.4 mm width is the result of the two together.HM88648 is a single-row tapered roller bearing in the HM88600-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Digit by digit, HM88648 reads as cone reference / cup reference in the HM88600-series inch series; the 35.717 mm bore, 72.233 mm OD and 25.4 mm width are the metric equivalents of the original inch boundary values. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "On this 35.717 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight HM88648 pair heats, loses setting control and smears the roller-rib contact.", "The HM88600-series inch series at 35.717 mm bore (72.233×25.4 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common HM88648 mounting error.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HM88648 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 72.233 mm cup race release as noise within the first running hours.", "The 83/90 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM88648 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 88648/610 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single HM88648 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HM88648 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM88648 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HM88648?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 25.4 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HM88648 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM88648?", "a": "The SKF HM 88648/610 is a single-row tapered roller bearing with 35.717 mm bore, 72.233 mm outer diameter and 25.4 mm width (1.406 × 2.844 × 1 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 83 kN, C0 90 kN, fatigue load limit Pu 10 kN, reference speed 7,500 r/min, limiting speed 9,000 r/min, mass about 490 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "HM88648-HM88610", "equiv_brand": "NTN", "level": "partial", "note": "Same 35.717×72.233×25.4 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "HM88648-HM88611AS", "equiv_brand": "NTN", "level": "partial", "note": "Same 35.717×72.233×25.4 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "HM88648-610", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM88648-610" ], "locale_variants": {} }, { "sku": "25880-25820", "brand": "SKF", "manufacturer_designation": "SKF 25880/25820", "series": "25800-series", "type": "tapered_roller", "d_mm": 36.487, "D_mm": 73.025, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 89.1, "static_load_kN": 88, "fatigue_load_limit_kN": 9.8, "max_rpm": 9500, "reference_speed_rpm": 8000, "limiting_speed_rpm": 9500, "weight_g": 460, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Specify pairs rather than single units wherever thrust reverses: the tapered contact of 25880 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Speed envelope and thermal behaviour: at 8,000 r/min thermal reference, the 36.487 mm bore shaft runs at a dn of 292k, and the 18.3 mm section dissipates heat through the cup-to-housing contact path; the 9,500 r/min mechanical ceiling reflects cage strength, and the 460 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cup-side note for 25820: the outer ring's rib profile and the 73.025 mm outside diameter are cup-specific within the 25800-series tables, so substituting a different cup against the same 25880 cone changes both the assembled 23.812 mm width and the axial free-play setting of the mounted pair.SKF 25880/25820 belongs to the SKF single-row tapered roller range — the 36.487 mm bore entry in the inch 25800-series, dimensioned 73.025 mm OD and 23.812 mm wide.In SKF inch-series tables 25880 sits at 36.487 mm bore (1.436 in) with a 73.025 mm cup OD and 23.812 mm total width — dimensions that trace back to the original Timken boundary plan for the 25800-series family. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. At 8,000 r/min reference speed the 18.3 mm-section 25880 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 9,500 r/min as the mechanical ceiling.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "On this 36.487 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 25880 pair heats, loses setting control and smears the roller-rib contact.", "The 25800-series inch series at 36.487 mm bore (73.025×23.812 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 25880 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 25880 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Catalogue reference speed and limiting speed are different limits: the 8,000 r/min reference is a thermal criterion under load, while the 9,500 r/min limiting value is the mechanical ceiling — observe both.", "The 89.1/88 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 25880 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 25880/25820 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 25880 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 25880 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 25880?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 23.812 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 25880 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 25880?", "a": "The SKF 25880/25820 is a single-row tapered roller bearing with 36.487 mm bore, 73.025 mm outer diameter and 23.812 mm width (1.436 × 2.875 × 0.937 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 89.1 kN, C0 88 kN, fatigue load limit Pu 9.8 kN, reference speed 8,000 r/min, limiting speed 9,500 r/min, mass about 460 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 25880 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 25800-series code marks the dimensional series. The metric dimensions 36.487×73.025×23.812 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "25880-25821", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25880-25820", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "25880-25820" ], "locale_variants": {} }, { "sku": "HM89449-410", "brand": "SKF", "manufacturer_designation": "SKF HM 89449/410", "series": "HM89400-series", "type": "tapered_roller", "d_mm": 36.512, "D_mm": 76.2, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 95.2, "static_load_kN": 106, "fatigue_load_limit_kN": 11.8, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500, "weight_g": 640, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " With C 95.2 kN and C0 106 kN, the HM89449 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 8,500 r/min. A single HM89449 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Journal and housing interface: the 36.512 mm bore takes a k5 shaft seat (upper deviation ~0.073 mm for this diameter range) and the 76.2 mm outside diameter pairs with an H7 housing bore tolerance band of 76.2.000/76.220 mm; the 29.37 mm width defines the shoulder depth, and the 640 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Inch tapered bearings are matched sets, not mix-and-match components: HM89449 pairs the HM 89449 cone with the 410 cup under the HM89400-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.In SKF catalogue PUB BU/P1 17000, HM89449 appears as SKF HM 89449/410: an open, single-row tapered roller bearing in the HM89400-series, supplied with a pressed-steel cage as standard.On the SKF nameplate, HM89449 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the HM89400-series marking the dimensional series. In SKF suffix language a bare HM89449 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 36.512 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight HM89449 pair heats, loses setting control and smears the roller-rib contact.", "The HM89400-series inch series at 36.512 mm bore (76.2×29.37 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single HM89449 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "A single HM89449 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The HM89449 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 95.2/106 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM89449 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 89449/410 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single HM89449 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HM89449 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM89449 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HM89449?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 29.37 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HM89449 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM89449?", "a": "The SKF HM 89449/410 is a single-row tapered roller bearing with 36.512 mm bore, 76.2 mm outer diameter and 29.37 mm width (1.437 × 3 × 1.156 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 95.2 kN, C0 106 kN, fatigue load limit Pu 11.8 kN, reference speed 7,000 r/min, limiting speed 8,500 r/min, mass about 640 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "HM89449-HM89411", "equiv_brand": "NTN", "level": "partial", "note": "Same 36.512×76.2×29.37 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "HM89449-410", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM89449-410" ], "locale_variants": {} }, { "sku": "LM29748-710", "brand": "SKF", "manufacturer_designation": "SKF LM 29748/710", "series": "LM29700-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 65.088, "B_mm": 18.034, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 53, "static_load_kN": 57, "fatigue_load_limit_kN": 6.1, "max_rpm": 10000, "reference_speed_rpm": 8000, "limiting_speed_rpm": 10000, "weight_g": 230, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Speed envelope and thermal behaviour: at 8,000 r/min thermal reference, the 38.1 mm bore shaft runs at a dn of 305k, and the 13.5 mm section dissipates heat through the cup-to-housing contact path; the 10,000 r/min mechanical ceiling reflects cage strength, and the 230 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cone-and-cup identity in LM29748: the leading LM 29748 reference identifies the inner ring, rollers and cage; the trailing 710 reference identifies the outer ring. The LM29700-series series lists alternative cups for the same cone, each producing a different 65.088 mm OD or 18.034 mm width — hence a different SKU even though the bore stays at 38.1 mm.In SKF catalogue PUB BU/P1 17000, LM29748 appears as SKF LM 29748/710: an open, single-row tapered roller bearing in the LM29700-series, supplied with a pressed-steel cage as standard.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (LM29700-series) ties the pair to a specific boundary plan. Dimensions 38.1×65.088×18.034 mm are the converted metric envelope. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Selection arithmetic: the C0/C ratio is about 1.08 (static 57 kN against dynamic 53 kN), typical of a tapered roller sized for axial capacity, and the 6.1 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Specify pairs rather than single units wherever thrust reverses: the tapered contact of LM29748 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "On this 38.1 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM29748 pair heats, loses setting control and smears the roller-rib contact.", "The LM29700-series inch series at 38.1 mm bore (65.088×18.034 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the LM29748 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "At the 53 kN rating of LM29748, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 10,000 r/min speed end and heavier preload only where moment stiffness dominates.", "The 230 g mass and 18.034 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of LM29748.", "The 53/57 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM29748 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 29748/710 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit LM29748?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 18.034 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM29748 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM29748?", "a": "The SKF LM 29748/710 is a single-row tapered roller bearing with 38.1 mm bore, 65.088 mm outer diameter and 18.034 mm width (1.5 × 2.563 × 0.71 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 53 kN, C0 57 kN, fatigue load limit Pu 6.1 kN, reference speed 8,000 r/min, limiting speed 10,000 r/min, mass about 230 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM29748 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM29700-series code marks the dimensional series. The metric dimensions 38.1×65.088×18.034 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM29748 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM29700-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "LM29748-LM29710", "equiv_brand": "NTN", "level": "partial", "note": "Same 38.1×65.088×18.034 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "LM29748-710", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM29748-710" ], "locale_variants": {} }, { "sku": "LM29749-710", "brand": "SKF", "manufacturer_designation": "SKF LM 29749/710", "series": "LM29700-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 65.088, "B_mm": 18.034, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 53, "static_load_kN": 57, "fatigue_load_limit_kN": 6.1, "max_rpm": 10000, "reference_speed_rpm": 8000, "limiting_speed_rpm": 10000, "weight_g": 240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF LM29749 (SKF LM 29749/710) is the LM29700-series tapered roller choice for a 38.1 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 65.088×18.034 mm envelope.Reading the designation: LM29749 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the LM29700-series code identifies the dimensional series. The 38.1 mm bore, 65.088 mm OD and 18.034 mm width are the metric equivalents of the inch boundary dimensions. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. At 8,000 r/min reference speed the 13.5 mm-section LM29749 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 10,000 r/min as the mechanical ceiling. A single LM29749 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Cross-section geometry: the 13.5 mm half-section ((65.088−38.1)/2) of this LM200-series unit places the roller large-end pitch diameter at roughly 51 mm, and the 18.034 mm axial width is split between cone (10 mm) and cup rib (8 mm) — a geometry that sets the contact angle and, with the 240 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Cup-side note for 710: the outer ring's rib profile and the 65.088 mm outside diameter are cup-specific within the LM29700-series tables, so substituting a different cup against the same LM 29749 cone changes both the assembled 18.034 mm width and the axial free-play setting of the mounted pair.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 38.1 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM29749 pair heats, loses setting control and smears the roller-rib contact.", "The LM29700-series inch series at 38.1 mm bore (65.088×18.034 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the LM29749 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the LM29749 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 53/57 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM29749 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 29749/710 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of LM29749?", "a": "The SKF LM 29749/710 is a single-row tapered roller bearing with 38.1 mm bore, 65.088 mm outer diameter and 18.034 mm width (1.5 × 2.563 × 0.71 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 53 kN, C0 57 kN, fatigue load limit Pu 6.1 kN, reference speed 8,000 r/min, limiting speed 10,000 r/min, mass about 240 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM29749 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM29700-series code marks the dimensional series. The metric dimensions 38.1×65.088×18.034 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM29749 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM29700-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM29749 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM29749 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM29749 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "LM29749-710", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM29749-710" ], "locale_variants": {} }, { "sku": "LM29749-711", "brand": "SKF", "manufacturer_designation": "SKF LM 29749/711", "series": "LM29700-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 65.088, "B_mm": 19.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 53, "static_load_kN": 57, "fatigue_load_limit_kN": 6.1, "max_rpm": 10000, "reference_speed_rpm": 8000, "limiting_speed_rpm": 10000, "weight_g": 250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (LM29700-series) ties the pair to a specific boundary plan. Dimensions 38.1×65.088×19.812 mm are the converted metric envelope. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Speed planning uses two different ceilings: 8,000 r/min thermal reference and 10,000 r/min mechanical limiting speed. Specify pairs rather than single units wherever thrust reverses: the tapered contact of LM29749 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Journal and housing interface: the 38.1 mm bore takes a k5 shaft seat (upper deviation ~0.076 mm for this diameter range) and the 65.088 mm outside diameter pairs with an H7 housing bore tolerance band of 65.088.000/65.108 mm; the 19.812 mm width defines the shoulder depth, and the 250 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. The cup reference 711 is structural, not a suffix: it identifies the outer ring that, combined with the LM 29749 cone, produces the 38.1/65.088/19.812 mm envelope catalogue-listed as LM29749. Quote the cup number in full when ordering — the LM29700-series tables contain other cups that fit the same cone but change the bearing.Ordering number SKF LM 29749/711 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 38.1 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 38.1 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM29749 pair heats, loses setting control and smears the roller-rib contact.", "The LM29700-series inch series at 38.1 mm bore (65.088×19.812 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common LM29749 mounting error.", "Do not mix brands or executions inside one LM29749 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 65.088 mm cup race release as noise within the first running hours.", "The 53/57 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM29749 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 29749/711 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the LM29749 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM29700-series code marks the dimensional series. The metric dimensions 38.1×65.088×19.812 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM29749 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM29700-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM29749 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM29749 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM29749 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM29749?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 19.812 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "LM29749-711", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM29749-711" ], "locale_variants": {} }, { "sku": "16150-16284", "brand": "SKF", "manufacturer_designation": "SKF 16150/16284", "series": "16000-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 72.238, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 60.3, "static_load_kN": 60, "fatigue_load_limit_kN": 6.55, "max_rpm": 9500, "reference_speed_rpm": 8000, "limiting_speed_rpm": 9500, "weight_g": 360, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Operating context for the 38.1 mm bore: a shaft of this diameter in the medium-bore band typically runs between 30480 and 45720 r/min in real machinery, and the 72.238 mm outside diameter places the housing shoulder at 80 mm outer abutment; the 20.638 mm width and 360 g mass together set the shaft critical speed and the housing resonance check for this 16100-series envelope. Cone versus cup responsibility in 16150: the 16150 cone carries the 38.1 mm bore, rollers and pressed-steel cage; the 16284 cup carries the 72.238 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.Ordering number SKF 16150/16284 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 38.1 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.Digit by digit, 16150 reads as cone reference / cup reference in the 16000-series inch series; the 38.1 mm bore, 72.238 mm OD and 20.638 mm width are the metric equivalents of the original inch boundary values. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Selection arithmetic: the C0/C ratio is about 1.00 (static 60 kN against dynamic 60.3 kN), typical of a tapered roller sized for axial capacity, and the 6.55 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 16150 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "On this 38.1 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 16150 pair heats, loses setting control and smears the roller-rib contact.", "The 16000-series inch series at 38.1 mm bore (72.238×20.638 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 16150 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Do not mix brands or executions inside one 16150 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 60.3/60 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 16150 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 16150/16284 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 16150?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 20.638 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 16150 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 16150?", "a": "The SKF 16150/16284 is a single-row tapered roller bearing with 38.1 mm bore, 72.238 mm outer diameter and 20.638 mm width (1.5 × 2.844 × 0.813 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 60.3 kN, C0 60 kN, fatigue load limit Pu 6.55 kN, reference speed 8,000 r/min, limiting speed 9,500 r/min, mass about 360 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 16150 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 16000-series code marks the dimensional series. The metric dimensions 38.1×72.238×20.638 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 16150 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (16000-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "16150-16282", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "16150-16284", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "16150-16284" ], "locale_variants": {} }, { "sku": "16150-16283", "brand": "SKF", "manufacturer_designation": "SKF 16150/16283", "series": "16000-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 72.238, "B_mm": 23.813, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 60.3, "static_load_kN": 60, "fatigue_load_limit_kN": 6.55, "max_rpm": 9500, "reference_speed_rpm": 8000, "limiting_speed_rpm": 9500, "weight_g": 390, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 16150/16283 is a 38.1×72.238×23.813 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.In SKF inch-series tables 16150 sits at 38.1 mm bore (1.5 in) with a 72.238 mm cup OD and 23.813 mm total width — dimensions that trace back to the original Timken boundary plan for the 16000-series family. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 390 g for the 38.1×72.238×23.813 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Fit selection follows the rotating ring — interference on a rotating cone — and two 16150 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Journal and housing interface: the 38.1 mm bore takes a k5 shaft seat (upper deviation ~0.076 mm for this diameter range) and the 72.238 mm outside diameter pairs with an H7 housing bore tolerance band of 72.238.000/72.258 mm; the 23.813 mm width defines the shoulder depth, and the 390 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Cup-side note for 16283: the outer ring's rib profile and the 72.238 mm outside diameter are cup-specific within the 16000-series tables, so substituting a different cup against the same 16150 cone changes both the assembled 23.813 mm width and the axial free-play setting of the mounted pair.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "machine-tool spindles" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "On this 38.1 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 16150 pair heats, loses setting control and smears the roller-rib contact.", "The 16000-series inch series at 38.1 mm bore (72.238×23.813 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one 16150 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Setting is a design value, not an assembly feel: excessive preload in the 16150 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The 16150 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 60.3/60 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 16150 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 16150/16283 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 16150?", "a": "The SKF 16150/16283 is a single-row tapered roller bearing with 38.1 mm bore, 72.238 mm outer diameter and 23.813 mm width (1.5 × 2.844 × 0.938 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 60.3 kN, C0 60 kN, fatigue load limit Pu 6.55 kN, reference speed 8,000 r/min, limiting speed 9,500 r/min, mass about 390 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 16150 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 16000-series code marks the dimensional series. The metric dimensions 38.1×72.238×23.813 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 16150 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (16000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 16150 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 16150 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 16150 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "16150-16282", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "16150-16283", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "16150-16283" ], "locale_variants": {} }, { "sku": "2788-2720", "brand": "SKF", "manufacturer_designation": "SKF 2788/2720", "series": "2700-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 76.2, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 92.1, "static_load_kN": 93, "fatigue_load_limit_kN": 10.4, "max_rpm": 9000, "reference_speed_rpm": 7500, "limiting_speed_rpm": 9000, "weight_g": 500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Inch tapered bearings are matched sets, not mix-and-match components: 2788 pairs the 2788 cone with the 2720 cup under the 2700-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.The SKF 2788/2720 is a 38.1×76.2×23.812 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.Numbering ties the bearing to its inch-series envelope: 2788 means a cone and cup matched pair in the 2700-series series — which is why the 38.1×76.2×23.812 mm outline swaps dimensionally with other inch-series bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Selection arithmetic: the C0/C ratio is about 1.01 (static 93 kN against dynamic 92.1 kN), typical of a tapered roller sized for axial capacity, and the 10.4 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Fit selection follows the rotating ring — interference on a rotating cone — and two 2788 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Operating context for the 38.1 mm bore: a shaft of this diameter in the medium-bore band typically runs between 30480 and 45720 r/min in real machinery, and the 76.2 mm outside diameter places the housing shoulder at 84 mm outer abutment; the 23.812 mm width and 500 g mass together set the shaft critical speed and the housing resonance check for this 27800-series envelope.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "On this 38.1 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 2788 pair heats, loses setting control and smears the roller-rib contact.", "The 2700-series inch series at 38.1 mm bore (76.2×23.812 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 2788 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Setting is a design value, not an assembly feel: excessive preload in the 2788 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Shaft and housing fillets must clear the bearing chamfer so the 23.812 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 92.1/93 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 2788 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 2788/2720 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 2788 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 2788?", "a": "The SKF 2788/2720 is a single-row tapered roller bearing with 38.1 mm bore, 76.2 mm outer diameter and 23.812 mm width (1.5 × 3 × 0.937 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 92.1 kN, C0 93 kN, fatigue load limit Pu 10.4 kN, reference speed 7,500 r/min, limiting speed 9,000 r/min, mass about 500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 2788 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 2700-series code marks the dimensional series. The metric dimensions 38.1×76.2×23.812 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 2788 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (2700-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 2788 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "2788-2720-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 38.1×76.2×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "2788-2720", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "2788-2720" ], "locale_variants": {} }, { "sku": "3490-3420", "brand": "SKF", "manufacturer_designation": "SKF 3490/3420", "series": "3400-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 79.375, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 112, "static_load_kN": 110, "fatigue_load_limit_kN": 12.5, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500, "weight_g": 680, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Journal and housing interface: the 38.1 mm bore takes a k5 shaft seat (upper deviation ~0.076 mm for this diameter range) and the 79.375 mm outside diameter pairs with an H7 housing bore tolerance band of 79.375.000/79.395 mm; the 29.37 mm width defines the shoulder depth, and the 680 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Cone versus cup responsibility in 3490: the 3490 cone carries the 38.1 mm bore, rollers and pressed-steel cage; the 3420 cup carries the 79.375 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.Ordering number SKF 3490/3420 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 38.1 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.The 3400-series series assigns 38.1 mm bore, 79.375 mm OD and 29.37 mm width to 3490; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. The 20.6 mm radial section height ((79.375−38.1)/2) and 680 g catalogue mass frame a 38.1 mm bore bearing rated at 112 kN C — roughly 2.94 kN of dynamic capacity per millimetre of bore before application factors. A single 3490 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 38.1 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 3490 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 38.1 mm bore (79.375×29.37 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "A single 3490 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 3490 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The 680 g mass and 29.37 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 3490.", "The 112/110 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 3490 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 3490/3420 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 3490?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 29.37 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 3490 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 3490?", "a": "The SKF 3490/3420 is a single-row tapered roller bearing with 38.1 mm bore, 79.375 mm outer diameter and 29.37 mm width (1.5 × 3.125 × 1.156 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 112 kN, C0 110 kN, fatigue load limit Pu 12.5 kN, reference speed 7,000 r/min, limiting speed 8,500 r/min, mass about 680 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 3490 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 3400-series code marks the dimensional series. The metric dimensions 38.1×79.375×29.37 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 3490 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (3400-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "3490-3420-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "3490-3420", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "3490-3420" ], "locale_variants": {} }, { "sku": "HM801346X-310", "brand": "SKF", "manufacturer_designation": "SKF HM 801346 X/310", "series": "HM801300-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 82.55, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 106, "static_load_kN": 118, "fatigue_load_limit_kN": 13.4, "max_rpm": 8000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 8000, "weight_g": 770, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Catalogue mass 770 g for the 38.1×82.55×29.37 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. For a 38.1 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two HM801346X bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Journal and housing interface: the 38.1 mm bore takes a k5 shaft seat (upper deviation ~0.076 mm for this diameter range) and the 82.55 mm outside diameter pairs with an H7 housing bore tolerance band of 82.55.000/82.570 mm; the 29.37 mm width defines the shoulder depth, and the 770 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Cone-and-cup identity in HM801346X: the leading HM 801346 X reference identifies the inner ring, rollers and cage; the trailing 310 reference identifies the outer ring. The HM801300-series series lists alternative cups for the same cone, each producing a different 82.55 mm OD or 29.37 mm width — hence a different SKU even though the bore stays at 38.1 mm.HM801346X is a single-row tapered roller bearing in the HM801300-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Numbering ties the bearing to its inch-series envelope: HM801346X means a cone and cup matched pair in the HM801300-series series — which is why the 38.1×82.55×29.37 mm outline swaps dimensionally with other inch-series bearings of the same code. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 38.1 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight HM801346X pair heats, loses setting control and smears the roller-rib contact.", "The HM801300-series inch series at 38.1 mm bore (82.55×29.37 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HM801346X pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "At the 106 kN rating of HM801346X, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 8,000 r/min speed end and heavier preload only where moment stiffness dominates.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 106/118 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM801346X (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 801346 X/310 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single HM801346X take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HM801346X compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM801346X position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HM801346X?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 29.37 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HM801346X interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM801346X?", "a": "The SKF HM 801346 X/310 is a single-row tapered roller bearing with 38.1 mm bore, 82.55 mm outer diameter and 29.37 mm width (1.5 × 3.25 × 1.156 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 106 kN, C0 118 kN, fatigue load limit Pu 13.4 kN, reference speed 6,700 r/min, limiting speed 8,000 r/min, mass about 770 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "HM801346X-310", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM801346X-310" ], "locale_variants": {} }, { "sku": "HM801346-310", "brand": "SKF", "manufacturer_designation": "SKF HM 801346/310", "series": "HM801300-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 82.55, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 106, "static_load_kN": 118, "fatigue_load_limit_kN": 13.4, "max_rpm": 8000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 8000, "weight_g": 780, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 38.1 mm shaft carrying combined load, SKF lists HM801346 under catalogue execution SKF HM 801346/310: one open single-row tapered roller bearing in the inch HM801300-series.On the SKF nameplate, HM801346 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the HM801300-series marking the dimensional series. In SKF suffix language a bare HM801346 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 13.4 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.11 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Because the contact line is tapered, one HM801346 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 38.1 mm shaft typically takes a k5 seat with an H7 housing bore. Dimensional interchange map: within the HM800 series at 38.1 mm bore, the 82.55 mm OD and 29.37 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 22.2 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 780 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Two catalogue entries share the HM 801346 cone but use different cups; this one, HM801346, takes the 310 cup and is ground for the resulting 82.55 mm OD / 29.37 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "belt-driven fan and blower shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "On this 38.1 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight HM801346 pair heats, loses setting control and smears the roller-rib contact.", "The HM801300-series inch series at 38.1 mm bore (82.55×29.37 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HM801346 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Setting is a design value, not an assembly feel: excessive preload in the HM801346 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Catalogue reference speed and limiting speed are different limits: the 6,700 r/min reference is a thermal criterion under load, while the 8,000 r/min limiting value is the mechanical ceiling — observe both.", "The 106/118 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM801346 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 801346/310 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of HM801346?", "a": "The SKF HM 801346/310 is a single-row tapered roller bearing with 38.1 mm bore, 82.55 mm outer diameter and 29.37 mm width (1.5 × 3.25 × 1.156 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 106 kN, C0 118 kN, fatigue load limit Pu 13.4 kN, reference speed 6,700 r/min, limiting speed 8,000 r/min, mass about 780 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM801346 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM801300-series code marks the dimensional series. The metric dimensions 38.1×82.55×29.37 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM801346 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM801300-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single HM801346 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HM801346 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM801346 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "HM801346-HM801310", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "HM801346-310", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM801346-310" ], "locale_variants": {} }, { "sku": "25572-25520", "brand": "SKF", "manufacturer_designation": "SKF 25572/25520", "series": "25500-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 82.931, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 99.1, "static_load_kN": 106, "fatigue_load_limit_kN": 11.8, "max_rpm": 8000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 8000, "weight_g": 650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 25572 the 25572 cone contributes the 38.1 mm bore and roller set, the 25520 cup contributes the 82.931 mm OD raceway, and the assembled 23.812 mm width is the catalogue value.SKF 25572 (SKF 25572/25520) is the 25500-series tapered roller choice for a 38.1 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 82.931×23.812 mm envelope.On the SKF nameplate, 25572 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 25500-series marking the dimensional series. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 99.1 kN and C0 106 kN, the 25572 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 8,000 r/min. Mounting practice for 25572: the rotating cone takes the interference fit (k5 on a 38.1 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Operating context for the 38.1 mm bore: a shaft of this diameter in the medium-bore band typically runs between 30480 and 45720 r/min in real machinery, and the 82.931 mm outside diameter places the housing shoulder at 91 mm outer abutment; the 23.812 mm width and 650 g mass together set the shaft critical speed and the housing resonance check for this 25500-series envelope.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "On this 38.1 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 25572 pair heats, loses setting control and smears the roller-rib contact.", "The 25500-series inch series at 38.1 mm bore (82.931×23.812 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 25572 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 25572 mounting error.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 82.931 mm cup race release as noise within the first running hours.", "The 99.1/106 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 25572 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 25572/25520 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 25572 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 25572?", "a": "The SKF 25572/25520 is a single-row tapered roller bearing with 38.1 mm bore, 82.931 mm outer diameter and 23.812 mm width (1.5 × 3.265 × 0.937 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 99.1 kN, C0 106 kN, fatigue load limit Pu 11.8 kN, reference speed 6,700 r/min, limiting speed 8,000 r/min, mass about 650 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 25572 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 25500-series code marks the dimensional series. The metric dimensions 38.1×82.931×23.812 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 25572 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (25500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 25572 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "25572-25520-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 38.1×82.931×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25572-25520", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "25572-25520" ], "locale_variants": {} }, { "sku": "418-414", "brand": "SKF", "manufacturer_designation": "SKF 418/414", "series": "415-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 88.5, "B_mm": 26.988, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 123, "static_load_kN": 114, "fatigue_load_limit_kN": 13.2, "max_rpm": 8500, "reference_speed_rpm": 6700, "limiting_speed_rpm": 8500, "weight_g": 830, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 418/414 is a 38.1×88.5×26.988 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (415-series) ties the pair to a specific boundary plan. Dimensions 38.1×88.5×26.988 mm are the converted metric envelope. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. With C 123 kN and C0 114 kN, the 418 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 8,500 r/min. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 418 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Cross-section geometry: the 25.2 mm half-section ((88.5−38.1)/2) of this 41800-series unit places the roller large-end pitch diameter at roughly 63 mm, and the 26.988 mm axial width is split between cone (15 mm) and cup rib (12 mm) — a geometry that sets the contact angle and, with the 830 g rotating cone mass, the critical speed at which cage-roller imbalance begins. From a specification standpoint the 414 cup is the controlling half of 418 for housing design — it sets the 88.5 mm OD and the outer abutment diameter — while the 418 cone controls shaft fit at the 38.1 mm bore; the 26.988 mm width is the result of the two together.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "On this 38.1 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 418 pair heats, loses setting control and smears the roller-rib contact.", "The 415-series inch series at 38.1 mm bore (88.5×26.988 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 418 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "A single 418 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Catalogue reference speed and limiting speed are different limits: the 6,700 r/min reference is a thermal criterion under load, while the 8,500 r/min limiting value is the mechanical ceiling — observe both.", "The 123/114 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 418 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 418/414 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 418?", "a": "The SKF 418/414 is a single-row tapered roller bearing with 38.1 mm bore, 88.5 mm outer diameter and 26.988 mm width (1.5 × 3.484 × 1.063 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 123 kN, C0 114 kN, fatigue load limit Pu 13.2 kN, reference speed 6,700 r/min, limiting speed 8,500 r/min, mass about 830 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 418 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 415-series code marks the dimensional series. The metric dimensions 38.1×88.5×26.988 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 418 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (415-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 418 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 418 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 418 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "418-414-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 38.1×88.5×26.988 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "418-414", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "418-414" ], "locale_variants": {} }, { "sku": "2789-2729", "brand": "SKF", "manufacturer_designation": "SKF 2789/2729", "series": "2700-series", "type": "tapered_roller", "d_mm": 39.688, "D_mm": 76.2, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 92.1, "static_load_kN": 93, "fatigue_load_limit_kN": 10.4, "max_rpm": 9000, "reference_speed_rpm": 7500, "limiting_speed_rpm": 9000, "weight_g": 480, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "On the SKF nameplate, 2789 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 2700-series marking the dimensional series. In SKF suffix language a bare 2789 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 7,500 r/min reference speed the 18.3 mm-section 2789 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 9,000 r/min as the mechanical ceiling. For a 39.688 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 2789 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Operating context for the 39.688 mm bore: a shaft of this diameter in the medium-bore band typically runs between 31750 and 47626 r/min in real machinery, and the 76.2 mm outside diameter places the housing shoulder at 84 mm outer abutment; the 23.812 mm width and 480 g mass together set the shaft critical speed and the housing resonance check for this 27800-series envelope. Two catalogue entries share the 2789 cone but use different cups; this one, 2789, takes the 2729 cup and is ground for the resulting 76.2 mm OD / 23.812 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.For a 39.688 mm shaft carrying combined load, SKF lists 2789 under catalogue execution SKF 2789/2729: one open single-row tapered roller bearing in the inch 2700-series.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "On this 39.688 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 2789 pair heats, loses setting control and smears the roller-rib contact.", "The 2700-series inch series at 39.688 mm bore (76.2×23.812 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 2789 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Do not mix brands or executions inside one 2789 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Open 2789 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 92.1/93 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 2789 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 2789/2729 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 2789 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 2700-series code marks the dimensional series. The metric dimensions 39.688×76.2×23.812 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 2789 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (2700-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 2789 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 2789 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 2789 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 2789?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 23.812 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "2789-2720", "equiv_brand": "NTN", "level": "partial", "note": "Same 39.688×76.2×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "2789-2729", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "2789-2729" ], "locale_variants": {} }, { "sku": "344-332", "brand": "SKF", "manufacturer_designation": "SKF 344/332", "series": "335-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 80, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 87.6, "static_load_kN": 80, "fatigue_load_limit_kN": 9.15, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500, "weight_g": 470, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Cross-section geometry: the 20.0 mm half-section ((80−40)/2) of this 34400-series unit places the roller large-end pitch diameter at roughly 60 mm, and the 21 mm axial width is split between cone (12 mm) and cup rib (9 mm) — a geometry that sets the contact angle and, with the 470 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Housing and abutment design flows from the cup: in 344 the 332 cup fixes the 80 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the 344 cone determines the 40 mm shaft interface; the 21 mm width is the assembled pair value.In SKF catalogue PUB BU/P1 17000, 344 appears as SKF 344/332: an open, single-row tapered roller bearing in the 335-series, supplied with a pressed-steel cage as standard.The 335-series series assigns 40 mm bore, 80 mm OD and 21 mm width to 344; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 87.6 kN and C0 80 kN, the 344 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 8,500 r/min. A single 344 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "On this 40 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 344 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 40 mm bore (80×21 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "A single 344 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "A single 344 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Open 344 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 87.6/80 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 344 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 344/332 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 344?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 21 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 344 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 344?", "a": "The SKF 344/332 is a single-row tapered roller bearing with 40 mm bore, 80 mm outer diameter and 21 mm width (1.575 × 3.15 × 0.827 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 87.6 kN, C0 80 kN, fatigue load limit Pu 9.15 kN, reference speed 7,000 r/min, limiting speed 8,500 r/min, mass about 470 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 344 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 335-series code marks the dimensional series. The metric dimensions 40×80×21 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 344 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (335-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "344-332-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 40×80×21 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "344-332", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "344-332" ], "locale_variants": {} }, { "sku": "344-332AA", "brand": "SKF", "manufacturer_designation": "SKF 344/332 AA", "series": "335-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 80, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 87.6, "static_load_kN": 80, "fatigue_load_limit_kN": 9.15, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500, "weight_g": 470, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " At 7,000 r/min reference speed the 20.0 mm-section 344 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 8,500 r/min as the mechanical ceiling. Because the contact line is tapered, one 344 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 40 mm shaft typically takes a k5 seat with an H7 housing bore. Dimensional interchange map: within the 34400 series at 40 mm bore, the 80 mm OD and 21 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 20.0 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 470 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. From a specification standpoint the 332 AA cup is the controlling half of 344 for housing design — it sets the 80 mm OD and the outer abutment diameter — while the 344 cone controls shaft fit at the 40 mm bore; the 21 mm width is the result of the two together.344 is a single-row tapered roller bearing in the 335-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Numbering ties the bearing to its inch-series envelope: 344 means a cone and cup matched pair in the 335-series series — which is why the 40×80×21 mm outline swaps dimensionally with other inch-series bearings of the same code. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "On this 40 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 344 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 40 mm bore (80×21 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 344 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 344 mounting error.", "Catalogue reference speed and limiting speed are different limits: the 7,000 r/min reference is a thermal criterion under load, while the 8,500 r/min limiting value is the mechanical ceiling — observe both.", "The 87.6/80 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 344 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 344/332 AA designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 344 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 344 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 344 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 344?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 21 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 344 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 344?", "a": "The SKF 344/332 AA is a single-row tapered roller bearing with 40 mm bore, 80 mm outer diameter and 21 mm width (1.575 × 3.15 × 0.827 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 87.6 kN, C0 80 kN, fatigue load limit Pu 9.15 kN, reference speed 7,000 r/min, limiting speed 8,500 r/min, mass about 470 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "344-332-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 40×80×21 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "344-332AA", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "344-332AA" ], "locale_variants": {} }, { "sku": "344A-332", "brand": "SKF", "manufacturer_designation": "SKF 344 A/332", "series": "335-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 80, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 87.6, "static_load_kN": 80, "fatigue_load_limit_kN": 9.15, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500, "weight_g": 480, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 480 g for the 40×80×21 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 344A generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Load system: the 87.6 kN basic dynamic rating C and 80 kN static rating C0 give a C0/C balance of 0.91, and dividing C by the 40 mm bore yields 2.19 kN per millimetre of journal — a density metric that compares across families; the 9.15 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 40 mm shaft carrying variable duty. Cup-side note for 332: the outer ring's rib profile and the 80 mm outside diameter are cup-specific within the 335-series tables, so substituting a different cup against the same 344 A cone changes both the assembled 21 mm width and the axial free-play setting of the mounted pair.SKF 344A (SKF 344 A/332) is the 335-series tapered roller choice for a 40 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 80×21 mm envelope.On the SKF nameplate, 344A denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 335-series marking the dimensional series.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 40 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 344A pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 40 mm bore (80×21 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "Do not mix brands or executions inside one 344A pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Setting is a design value, not an assembly feel: excessive preload in the 344A pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Shaft and housing fillets must clear the bearing chamfer so the 21 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 87.6/80 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 344A (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 344 A/332 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in 344A mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (335-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 344A take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 344A compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 344A position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 344A?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 21 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 344A interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "344A-332", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "344A-332" ], "locale_variants": {} }, { "sku": "LM300849-811", "brand": "SKF", "manufacturer_designation": "SKF LM 300849/811", "series": "LM300800-series", "type": "tapered_roller", "d_mm": 41, "D_mm": 68, "B_mm": 17.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 53.6, "static_load_kN": 58.5, "fatigue_load_limit_kN": 6.3, "max_rpm": 9500, "reference_speed_rpm": 8000, "limiting_speed_rpm": 9500, "weight_g": 240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Speed envelope and thermal behaviour: at 8,000 r/min thermal reference, the 41 mm bore shaft runs at a dn of 328k, and the 13.5 mm section dissipates heat through the cup-to-housing contact path; the 9,500 r/min mechanical ceiling reflects cage strength, and the 240 g spinning cone contributes gyroscopic moment under rapid speed reversal. From a specification standpoint the 811 cup is the controlling half of LM300849 for housing design — it sets the 68 mm OD and the outer abutment diameter — while the LM 300849 cone controls shaft fit at the 41 mm bore; the 17.5 mm width is the result of the two together.The SKF LM 300849/811 is a 41×68×17.5 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.Numbering ties the bearing to its inch-series envelope: LM300849 means a cone and cup matched pair in the LM300800-series series — which is why the 41×68×17.5 mm outline swaps dimensionally with other inch-series bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 6.3 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.09 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Specify pairs rather than single units wherever thrust reverses: the tapered contact of LM300849 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "On this 41 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM300849 pair heats, loses setting control and smears the roller-rib contact.", "The LM300800-series inch series at 41 mm bore (68×17.5 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one LM300849 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common LM300849 mounting error.", "Shaft and housing fillets must clear the bearing chamfer so the 17.5 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 53.6/58.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM300849 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 300849/811 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit LM300849?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 17.5 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM300849 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM300849?", "a": "The SKF LM 300849/811 is a single-row tapered roller bearing with 41 mm bore, 68 mm outer diameter and 17.5 mm width (1.614 × 2.677 × 0.689 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 53.6 kN, C0 58.5 kN, fatigue load limit Pu 6.3 kN, reference speed 8,000 r/min, limiting speed 9,500 r/min, mass about 240 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM300849 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM300800-series code marks the dimensional series. The metric dimensions 41×68×17.5 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM300849 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM300800-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "LM300849-LM300811", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "LM300849-811", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM300849-811" ], "locale_variants": {} }, { "sku": "18590-18520", "brand": "SKF", "manufacturer_designation": "SKF 18590/18520", "series": "18500-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 73.025, "B_mm": 16.667, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 57.7, "static_load_kN": 56, "fatigue_load_limit_kN": 6.2, "max_rpm": 9000, "reference_speed_rpm": 7500, "limiting_speed_rpm": 9000, "weight_g": 280, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Operating context for the 41.275 mm bore: a shaft of this diameter in the medium-bore band typically runs between 33020 and 49530 r/min in real machinery, and the 73.025 mm outside diameter places the housing shoulder at 81 mm outer abutment; the 16.667 mm width and 280 g mass together set the shaft critical speed and the housing resonance check for this 18500-series envelope. Cone-and-cup identity in 18590: the leading 18590 reference identifies the inner ring, rollers and cage; the trailing 18520 reference identifies the outer ring. The 18500-series series lists alternative cups for the same cone, each producing a different 73.025 mm OD or 16.667 mm width — hence a different SKU even though the bore stays at 41.275 mm.The SKF 18590/18520 is a 41.275×73.025×16.667 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.Numbering ties the bearing to its inch-series envelope: 18590 means a cone and cup matched pair in the 18500-series series — which is why the 41.275×73.025×16.667 mm outline swaps dimensionally with other inch-series bearings of the same code. In SKF suffix language a bare 18590 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 15.9 mm radial section height ((73.025−41.275)/2) and 280 g catalogue mass frame a 41.275 mm bore bearing rated at 57.7 kN C — roughly 1.40 kN of dynamic capacity per millimetre of bore before application factors. A single 18590 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 41.275 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 18590 pair heats, loses setting control and smears the roller-rib contact.", "The 18500-series inch series at 41.275 mm bore (73.025×16.667 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one 18590 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Do not mix brands or executions inside one 18590 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Catalogue reference speed and limiting speed are different limits: the 7,500 r/min reference is a thermal criterion under load, while the 9,000 r/min limiting value is the mechanical ceiling — observe both.", "The 57.7/56 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 18590 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 18590/18520 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 18590?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 16.667 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 18590 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 18590?", "a": "The SKF 18590/18520 is a single-row tapered roller bearing with 41.275 mm bore, 73.025 mm outer diameter and 16.667 mm width (1.625 × 2.875 × 0.656 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 57.7 kN, C0 56 kN, fatigue load limit Pu 6.2 kN, reference speed 7,500 r/min, limiting speed 9,000 r/min, mass about 280 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 18590 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 18500-series code marks the dimensional series. The metric dimensions 41.275×73.025×16.667 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 18590 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (18500-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "18590-18520-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 41.275×73.025×16.667 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "18590-18520", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "18590-18520" ], "locale_variants": {} }, { "sku": "LM501349-310", "brand": "SKF", "manufacturer_designation": "SKF LM 501349/310", "series": "LM501300-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 73.431, "B_mm": 19.558, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 67.6, "static_load_kN": 68, "fatigue_load_limit_kN": 7.65, "max_rpm": 9000, "reference_speed_rpm": 7500, "limiting_speed_rpm": 9000, "weight_g": 340, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Cone-and-cup identity in LM501349: the leading LM 501349 reference identifies the inner ring, rollers and cage; the trailing 310 reference identifies the outer ring. The LM501300-series series lists alternative cups for the same cone, each producing a different 73.431 mm OD or 19.558 mm width — hence a different SKU even though the bore stays at 41.275 mm.In SKF catalogue PUB BU/P1 17000, LM501349 appears as SKF LM 501349/310: an open, single-row tapered roller bearing in the LM501300-series, supplied with a pressed-steel cage as standard.In SKF inch-series tables LM501349 sits at 41.275 mm bore (1.625 in) with a 73.431 mm cup OD and 19.558 mm total width — dimensions that trace back to the original Timken boundary plan for the LM501300-series family. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Selection arithmetic: the C0/C ratio is about 1.01 (static 68 kN against dynamic 67.6 kN), typical of a tapered roller sized for axial capacity, and the 7.65 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Specify pairs rather than single units wherever thrust reverses: the tapered contact of LM501349 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Load system: the 67.6 kN basic dynamic rating C and 68 kN static rating C0 give a C0/C balance of 1.01, and dividing C by the 41.275 mm bore yields 1.64 kN per millimetre of journal — a density metric that compares across families; the 7.65 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 41.275 mm shaft carrying variable duty.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "On this 41.275 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM501349 pair heats, loses setting control and smears the roller-rib contact.", "The LM501300-series inch series at 41.275 mm bore (73.431×19.558 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the LM501349 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "At the 67.6 kN rating of LM501349, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 9,000 r/min speed end and heavier preload only where moment stiffness dominates.", "Shaft and housing fillets must clear the bearing chamfer so the 19.558 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 67.6/68 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM501349 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 501349/310 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is LM501349 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM501349?", "a": "The SKF LM 501349/310 is a single-row tapered roller bearing with 41.275 mm bore, 73.431 mm outer diameter and 19.558 mm width (1.625 × 2.891 × 0.77 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 67.6 kN, C0 68 kN, fatigue load limit Pu 7.65 kN, reference speed 7,500 r/min, limiting speed 9,000 r/min, mass about 340 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM501349 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM501300-series code marks the dimensional series. The metric dimensions 41.275×73.431×19.558 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM501349 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM501300-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM501349 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "LM501349-LM501310", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "LM501349-LM501314", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "LM501349-310", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM501349-310" ], "locale_variants": {} }, { "sku": "LM501349-314", "brand": "SKF", "manufacturer_designation": "SKF LM 501349/314", "series": "LM501300-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 73.431, "B_mm": 21.43, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 67.6, "static_load_kN": 68, "fatigue_load_limit_kN": 7.65, "max_rpm": 9000, "reference_speed_rpm": 7500, "limiting_speed_rpm": 9000, "weight_g": 360, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Speed planning uses two different ceilings: 7,500 r/min thermal reference and 9,000 r/min mechanical limiting speed. Because the contact line is tapered, one LM501349 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 41.275 mm shaft typically takes a k5 seat with an H7 housing bore. Cross-section geometry: the 16.1 mm half-section ((73.431−41.275)/2) of this LM500-series unit places the roller large-end pitch diameter at roughly 57 mm, and the 21.43 mm axial width is split between cone (12 mm) and cup rib (10 mm) — a geometry that sets the contact angle and, with the 360 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Housing and abutment design flows from the cup: in LM501349 the 314 cup fixes the 73.431 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the LM 501349 cone determines the 41.275 mm shaft interface; the 21.43 mm width is the assembled pair value.Ordering number SKF LM 501349/314 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 41.275 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.Numbering ties the bearing to its inch-series envelope: LM501349 means a cone and cup matched pair in the LM501300-series series — which is why the 41.275×73.431×21.43 mm outline swaps dimensionally with other inch-series bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "machine-tool spindles" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "On this 41.275 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM501349 pair heats, loses setting control and smears the roller-rib contact.", "The LM501300-series inch series at 41.275 mm bore (73.431×21.43 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of LM501349 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "A single LM501349 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 73.431 mm cup race release as noise within the first running hours.", "The 67.6/68 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM501349 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 501349/314 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single LM501349 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM501349 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM501349 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM501349?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 21.43 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM501349 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM501349?", "a": "The SKF LM 501349/314 is a single-row tapered roller bearing with 41.275 mm bore, 73.431 mm outer diameter and 21.43 mm width (1.625 × 2.891 × 0.844 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 67.6 kN, C0 68 kN, fatigue load limit Pu 7.65 kN, reference speed 7,500 r/min, limiting speed 9,000 r/min, mass about 360 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "LM501349-LM501310", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "LM501349-LM501314", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "LM501349-314", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM501349-314" ], "locale_variants": {} }, { "sku": "11162-11300", "brand": "SKF", "manufacturer_designation": "SKF 11162/11300", "series": "11000-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 76.2, "B_mm": 18.009, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 55.7, "static_load_kN": 56, "fatigue_load_limit_kN": 6.1, "max_rpm": 9000, "reference_speed_rpm": 7000, "limiting_speed_rpm": 9000, "weight_g": 340, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The 6.1 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.01 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 11162 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Load system: the 55.7 kN basic dynamic rating C and 56 kN static rating C0 give a C0/C balance of 1.01, and dividing C by the 41.275 mm bore yields 1.35 kN per millimetre of journal — a density metric that compares across families; the 6.1 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 41.275 mm shaft carrying variable duty. Housing and abutment design flows from the cup: in 11162 the 11300 cup fixes the 76.2 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the 11162 cone determines the 41.275 mm shaft interface; the 18.009 mm width is the assembled pair value.SKF 11162 (SKF 11162/11300) is the 11000-series tapered roller choice for a 41.275 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 76.2×18.009 mm envelope.Digit by digit, 11162 reads as cone reference / cup reference in the 11000-series inch series; the 41.275 mm bore, 76.2 mm OD and 18.009 mm width are the metric equivalents of the original inch boundary values. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "On this 41.275 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 11162 pair heats, loses setting control and smears the roller-rib contact.", "The 11000-series inch series at 41.275 mm bore (76.2×18.009 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 11162 mounting error.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 11162 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Open 11162 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 55.7/56 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 11162 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 11162/11300 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 11162 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 11162 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 11162 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 11162?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 18.009 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 11162 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 11162?", "a": "The SKF 11162/11300 is a single-row tapered roller bearing with 41.275 mm bore, 76.2 mm outer diameter and 18.009 mm width (1.625 × 3 × 0.709 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 55.7 kN, C0 56 kN, fatigue load limit Pu 6.1 kN, reference speed 7,000 r/min, limiting speed 9,000 r/min, mass about 340 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "11162-11300-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 41.275×76.2×18.009 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "11162-11315", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "11162-11300", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "11162-11300" ], "locale_variants": {} }, { "sku": "11163-11300", "brand": "SKF", "manufacturer_designation": "SKF 11163/11300", "series": "11000-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 76.2, "B_mm": 18.009, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 55.7, "static_load_kN": 56, "fatigue_load_limit_kN": 6.1, "max_rpm": 9000, "reference_speed_rpm": 7000, "limiting_speed_rpm": 9000, "weight_g": 340, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Selection arithmetic: the C0/C ratio is about 1.01 (static 56 kN against dynamic 55.7 kN), typical of a tapered roller sized for axial capacity, and the 6.1 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 11163 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Operating context for the 41.275 mm bore: a shaft of this diameter in the medium-bore band typically runs between 33020 and 49530 r/min in real machinery, and the 76.2 mm outside diameter places the housing shoulder at 84 mm outer abutment; the 18.009 mm width and 340 g mass together set the shaft critical speed and the housing resonance check for this 11100-series envelope. Inch tapered bearings are matched sets, not mix-and-match components: 11163 pairs the 11163 cone with the 11300 cup under the 11000-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.Ordering number SKF 11163/11300 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 41.275 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (11000-series) ties the pair to a specific boundary plan. Dimensions 41.275×76.2×18.009 mm are the converted metric envelope. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "On this 41.275 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 11163 pair heats, loses setting control and smears the roller-rib contact.", "The 11000-series inch series at 41.275 mm bore (76.2×18.009 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 11163 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Do not mix brands or executions inside one 11163 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Shaft and housing fillets must clear the bearing chamfer so the 18.009 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 55.7/56 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 11163 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 11163/11300 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 11163 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 11163 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 11163 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 11163?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 18.009 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 11163 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 11163?", "a": "The SKF 11163/11300 is a single-row tapered roller bearing with 41.275 mm bore, 76.2 mm outer diameter and 18.009 mm width (1.625 × 3 × 0.709 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 55.7 kN, C0 56 kN, fatigue load limit Pu 6.1 kN, reference speed 7,000 r/min, limiting speed 9,000 r/min, mass about 340 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "11163-11300", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "11163-11300" ], "locale_variants": {} }, { "sku": "24780-24720", "brand": "SKF", "manufacturer_designation": "SKF 24780/24720", "series": "24700-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 76.2, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 84.2, "static_load_kN": 86.5, "fatigue_load_limit_kN": 9.65, "max_rpm": 9000, "reference_speed_rpm": 7000, "limiting_speed_rpm": 9000, "weight_g": 440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Two catalogue entries share the 24780 cone but use different cups; this one, 24780, takes the 24720 cup and is ground for the resulting 76.2 mm OD / 22.225 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.SKF 24780 (SKF 24780/24720) is the 24700-series tapered roller choice for a 41.275 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 76.2×22.225 mm envelope.Digit by digit, 24780 reads as cone reference / cup reference in the 24700-series inch series; the 41.275 mm bore, 76.2 mm OD and 22.225 mm width are the metric equivalents of the original inch boundary values. In SKF suffix language a bare 24780 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 9.65 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.03 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 24780 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Material and manufacturing detail: the 440 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 24700 ISO envelope, with the pressed-steel cage contributing roughly 13 g of the total; the 41.275 mm bore is ground to IT5 roundness and the 76.2 mm OD to IT5 cylindricity, and the 22.225 mm width tolerance keeps the pair-setting scatter within the ISO preload class.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "machine-tool spindles" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 41.275 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 24780 pair heats, loses setting control and smears the roller-rib contact.", "The 24700-series inch series at 41.275 mm bore (76.2×22.225 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 24780 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Setting is a design value, not an assembly feel: excessive preload in the 24780 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Catalogue reference speed and limiting speed are different limits: the 7,000 r/min reference is a thermal criterion under load, while the 9,000 r/min limiting value is the mechanical ceiling — observe both.", "The 84.2/86.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 24780 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 24780/24720 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 24780 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 24780?", "a": "The SKF 24780/24720 is a single-row tapered roller bearing with 41.275 mm bore, 76.2 mm outer diameter and 22.225 mm width (1.625 × 3 × 0.875 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 84.2 kN, C0 86.5 kN, fatigue load limit Pu 9.65 kN, reference speed 7,000 r/min, limiting speed 9,000 r/min, mass about 440 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 24780 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 24700-series code marks the dimensional series. The metric dimensions 41.275×76.2×22.225 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 24780 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (24700-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 24780 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "24780-24720-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 41.275×76.2×22.225 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "24780-24720", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "24780-24720" ], "locale_variants": {} }, { "sku": "M802048-011", "brand": "SKF", "manufacturer_designation": "SKF M 802048/011", "series": "M802000-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 82.55, "B_mm": 26.543, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 91.2, "static_load_kN": 91.5, "fatigue_load_limit_kN": 10.6, "max_rpm": 8000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 8000, "weight_g": 620, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. With C 91.2 kN and C0 91.5 kN, the M802048 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 8,000 r/min. Because the contact line is tapered, one M802048 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 41.275 mm shaft typically takes a k5 seat with an H7 housing bore. Load system: the 91.2 kN basic dynamic rating C and 91.5 kN static rating C0 give a C0/C balance of 1.00, and dividing C by the 41.275 mm bore yields 2.21 kN per millimetre of journal — a density metric that compares across families; the 10.6 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 41.275 mm shaft carrying variable duty. The cup reference 011 is structural, not a suffix: it identifies the outer ring that, combined with the M 802048 cone, produces the 41.275/82.55/26.543 mm envelope catalogue-listed as M802048. Quote the cup number in full when ordering — the M802000-series tables contain other cups that fit the same cone but change the bearing.SKF M802048 (SKF M 802048/011) is the M802000-series tapered roller choice for a 41.275 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 82.55×26.543 mm envelope.The M802000-series series assigns 41.275 mm bore, 82.55 mm OD and 26.543 mm width to M802048; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "belt-driven fan and blower shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "On this 41.275 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight M802048 pair heats, loses setting control and smears the roller-rib contact.", "The M802000-series inch series at 41.275 mm bore (82.55×26.543 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of M802048 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Do not mix brands or executions inside one M802048 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 82.55 mm cup race release as noise within the first running hours.", "The 91.2/91.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of M802048 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF M 802048/011 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in M802048 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (M802000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single M802048 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does M802048 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load M802048 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit M802048?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 26.543 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is M802048 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "M802048-M802011", "equiv_brand": "NTN", "level": "partial", "note": "Same 41.275×82.55×26.543 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "M802048-011", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "M802048-011" ], "locale_variants": {} }, { "sku": "3585-3525", "brand": "SKF", "manufacturer_designation": "SKF 3585/3525", "series": "3500-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 87.312, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 126, "static_load_kN": 132, "fatigue_load_limit_kN": 15, "max_rpm": 8000, "reference_speed_rpm": 6300, "limiting_speed_rpm": 8000, "weight_g": 850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Cross-section geometry: the 23.0 mm half-section ((87.312−41.275)/2) of this 35800-series unit places the roller large-end pitch diameter at roughly 64 mm, and the 30.162 mm axial width is split between cone (17 mm) and cup rib (14 mm) — a geometry that sets the contact angle and, with the 850 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Housing and abutment design flows from the cup: in 3585 the 3525 cup fixes the 87.312 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the 3585 cone determines the 41.275 mm shaft interface; the 30.162 mm width is the assembled pair value.SKF 3585/3525 belongs to the SKF single-row tapered roller range — the 41.275 mm bore entry in the inch 3500-series, dimensioned 87.312 mm OD and 30.162 mm wide.On the SKF nameplate, 3585 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 3500-series marking the dimensional series. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Speed planning uses two different ceilings: 6,300 r/min thermal reference and 8,000 r/min mechanical limiting speed. Because the contact line is tapered, one 3585 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 41.275 mm shaft typically takes a k5 seat with an H7 housing bore.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "On this 41.275 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 3585 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 41.275 mm bore (87.312×30.162 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "At the 126 kN rating of 3585, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 8,000 r/min speed end and heavier preload only where moment stiffness dominates.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 3585 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Open 3585 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 126/132 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 3585 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 3585/3525 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 3585?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 30.162 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 3585 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 3585?", "a": "The SKF 3585/3525 is a single-row tapered roller bearing with 41.275 mm bore, 87.312 mm outer diameter and 30.162 mm width (1.625 × 3.437 × 1.187 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 126 kN, C0 132 kN, fatigue load limit Pu 15 kN, reference speed 6,300 r/min, limiting speed 8,000 r/min, mass about 850 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 3585 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 3500-series code marks the dimensional series. The metric dimensions 41.275×87.312×30.162 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 3585 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (3500-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "3585-3525", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "3585-3525" ], "locale_variants": {} }, { "sku": "HM803146-110", "brand": "SKF", "manufacturer_designation": "SKF HM 803146/110", "series": "HM803100-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 88.9, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 116, "static_load_kN": 127, "fatigue_load_limit_kN": 14.6, "max_rpm": 7500, "reference_speed_rpm": 6000, "limiting_speed_rpm": 7500, "weight_g": 910, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Numbering ties the bearing to its inch-series envelope: HM803146 means a cone and cup matched pair in the HM803100-series series — which is why the 41.275×88.9×30.162 mm outline swaps dimensionally with other inch-series bearings of the same code. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Speed planning uses two different ceilings: 6,000 r/min thermal reference and 7,500 r/min mechanical limiting speed. Specify pairs rather than single units wherever thrust reverses: the tapered contact of HM803146 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Speed envelope and thermal behaviour: at 6,000 r/min thermal reference, the 41.275 mm bore shaft runs at a dn of 248k, and the 23.8 mm section dissipates heat through the cup-to-housing contact path; the 7,500 r/min mechanical ceiling reflects cage strength, and the 910 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cone versus cup responsibility in HM803146: the HM 803146 cone carries the 41.275 mm bore, rollers and pressed-steel cage; the 110 cup carries the 88.9 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.For a 41.275 mm shaft carrying combined load, SKF lists HM803146 under catalogue execution SKF HM 803146/110: one open single-row tapered roller bearing in the inch HM803100-series.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 41.275 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight HM803146 pair heats, loses setting control and smears the roller-rib contact.", "The HM803100-series inch series at 41.275 mm bore (88.9×30.162 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 116 kN rating of HM803146, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 7,500 r/min speed end and heavier preload only where moment stiffness dominates.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HM803146 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Shaft and housing fillets must clear the bearing chamfer so the 30.162 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 116/127 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM803146 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 803146/110 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the HM803146 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM803100-series code marks the dimensional series. The metric dimensions 41.275×88.9×30.162 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM803146 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM803100-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single HM803146 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HM803146 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM803146 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HM803146?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 30.162 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "HM803146-110", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM803146-110" ], "locale_variants": {} }, { "sku": "526-522", "brand": "SKF", "manufacturer_designation": "SKF 526/522", "series": "525-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 101.6, "B_mm": 34.925, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 184, "static_load_kN": 190, "fatigue_load_limit_kN": 21.6, "max_rpm": 6700, "reference_speed_rpm": 5600, "limiting_speed_rpm": 6700, "weight_g": 1450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " For a 41.275 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 526 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Journal and housing interface: the 41.275 mm bore takes a k5 shaft seat (upper deviation ~0.083 mm for this diameter range) and the 101.6 mm outside diameter pairs with an H7 housing bore tolerance band of 101.6.000/101.620 mm; the 34.925 mm width defines the shoulder depth, and the 1450 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Cone-and-cup identity in 526: the leading 526 reference identifies the inner ring, rollers and cage; the trailing 522 reference identifies the outer ring. The 525-series series lists alternative cups for the same cone, each producing a different 101.6 mm OD or 34.925 mm width — hence a different SKU even though the bore stays at 41.275 mm.SKF 526/522 belongs to the SKF single-row tapered roller range — the 41.275 mm bore entry in the inch 525-series, dimensioned 101.6 mm OD and 34.925 mm wide.Reading the designation: 526 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 525-series code identifies the dimensional series. The 41.275 mm bore, 101.6 mm OD and 34.925 mm width are the metric equivalents of the inch boundary dimensions. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Selection arithmetic: the C0/C ratio is about 1.03 (static 190 kN against dynamic 184 kN), typical of a tapered roller sized for axial capacity, and the 21.6 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "machine-tool spindles" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "On this 41.275 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 526 pair heats, loses setting control and smears the roller-rib contact.", "The 525-series inch series at 41.275 mm bore (101.6×34.925 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 526 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Setting is a design value, not an assembly feel: excessive preload in the 526 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Shaft and housing fillets must clear the bearing chamfer so the 34.925 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 184/190 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 526 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 526/522 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 526 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 526 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 526?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 34.925 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 526 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 526?", "a": "The SKF 526/522 is a single-row tapered roller bearing with 41.275 mm bore, 101.6 mm outer diameter and 34.925 mm width (1.625 × 4 × 1.375 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 184 kN, C0 190 kN, fatigue load limit Pu 21.6 kN, reference speed 5,600 r/min, limiting speed 6,700 r/min, mass about 1450 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 526 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 525-series code marks the dimensional series. The metric dimensions 41.275×101.6×34.925 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "526-522", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "526-522" ], "locale_variants": {} }, { "sku": "25577-25520", "brand": "SKF", "manufacturer_designation": "SKF 25577/25520", "series": "25500-series", "type": "tapered_roller", "d_mm": 42.875, "D_mm": 82.931, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 99.1, "static_load_kN": 106, "fatigue_load_limit_kN": 11.8, "max_rpm": 8000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 8000, "weight_g": 590, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Fit selection follows the rotating ring — interference on a rotating cone — and two 25577 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Load system: the 99.1 kN basic dynamic rating C and 106 kN static rating C0 give a C0/C balance of 1.07, and dividing C by the 42.875 mm bore yields 2.31 kN per millimetre of journal — a density metric that compares across families; the 11.8 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 42.875 mm shaft carrying variable duty. Two catalogue entries share the 25577 cone but use different cups; this one, 25577, takes the 25520 cup and is ground for the resulting 82.931 mm OD / 23.812 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.The SKF 25577/25520 is a 42.875×82.931×23.812 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.In SKF inch-series tables 25577 sits at 42.875 mm bore (1.688 in) with a 82.931 mm cup OD and 23.812 mm total width — dimensions that trace back to the original Timken boundary plan for the 25500-series family. In SKF suffix language a bare 25577 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 20.0 mm radial section height ((82.931−42.875)/2) and 590 g catalogue mass frame a 42.875 mm bore bearing rated at 99.1 kN C — roughly 2.31 kN of dynamic capacity per millimetre of bore before application factors.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "On this 42.875 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 25577 pair heats, loses setting control and smears the roller-rib contact.", "The 25500-series inch series at 42.875 mm bore (82.931×23.812 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 25577 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Setting is a design value, not an assembly feel: excessive preload in the 25577 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 82.931 mm cup race release as noise within the first running hours.", "The 99.1/106 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 25577 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 25577/25520 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 25577 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 25577 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 25577?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 23.812 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 25577 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 25577?", "a": "The SKF 25577/25520 is a single-row tapered roller bearing with 42.875 mm bore, 82.931 mm outer diameter and 23.812 mm width (1.688 × 3.265 × 0.937 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 99.1 kN, C0 106 kN, fatigue load limit Pu 11.8 kN, reference speed 6,700 r/min, limiting speed 8,000 r/min, mass about 590 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 25577 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 25500-series code marks the dimensional series. The metric dimensions 42.875×82.931×23.812 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "25577-25520-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 42.875×82.931×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25577-25520", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "25577-25520" ], "locale_variants": {} }, { "sku": "25577-25523", "brand": "SKF", "manufacturer_designation": "SKF 25577/25523", "series": "25500-series", "type": "tapered_roller", "d_mm": 42.875, "D_mm": 82.931, "B_mm": 26.988, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 99.1, "static_load_kN": 106, "fatigue_load_limit_kN": 12, "max_rpm": 8000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 8000, "weight_g": 630, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 42.875 mm shaft carrying combined load, SKF lists 25577 under catalogue execution SKF 25577/25523: one open single-row tapered roller bearing in the inch 25500-series.On the SKF nameplate, 25577 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 25500-series marking the dimensional series. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Speed planning uses two different ceilings: 6,700 r/min thermal reference and 8,000 r/min mechanical limiting speed. Mounting practice for 25577: the rotating cone takes the interference fit (k5 on a 42.875 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Operating context for the 42.875 mm bore: a shaft of this diameter in the medium-bore band typically runs between 34300 and 51450 r/min in real machinery, and the 82.931 mm outside diameter places the housing shoulder at 91 mm outer abutment; the 26.988 mm width and 630 g mass together set the shaft critical speed and the housing resonance check for this 25500-series envelope. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 25577 the 25577 cone contributes the 42.875 mm bore and roller set, the 25523 cup contributes the 82.931 mm OD raceway, and the assembled 26.988 mm width is the catalogue value.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "On this 42.875 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 25577 pair heats, loses setting control and smears the roller-rib contact.", "The 25500-series inch series at 42.875 mm bore (82.931×26.988 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 25577 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "A single 25577 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Shaft and housing fillets must clear the bearing chamfer so the 26.988 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 99.1/106 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 25577 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 25577/25523 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 25577?", "a": "The SKF 25577/25523 is a single-row tapered roller bearing with 42.875 mm bore, 82.931 mm outer diameter and 26.988 mm width (1.688 × 3.265 × 1.063 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 99.1 kN, C0 106 kN, fatigue load limit Pu 12 kN, reference speed 6,700 r/min, limiting speed 8,000 r/min, mass about 630 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 25577 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 25500-series code marks the dimensional series. The metric dimensions 42.875×82.931×26.988 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 25577 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (25500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 25577 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 25577 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 25577 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "25577-25520-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25577-25523", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "25577-25523" ], "locale_variants": {} }, { "sku": "25580-25520", "brand": "SKF", "manufacturer_designation": "SKF 25580/25520", "series": "25500-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 82.931, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 99.1, "static_load_kN": 106, "fatigue_load_limit_kN": 11.8, "max_rpm": 8000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 8000, "weight_g": 570, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Digit by digit, 25580 reads as cone reference / cup reference in the 25500-series inch series; the 44.45 mm bore, 82.931 mm OD and 23.812 mm width are the metric equivalents of the original inch boundary values. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 570 g for the 44.45×82.931×23.812 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Fit selection follows the rotating ring — interference on a rotating cone — and two 25580 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Dimensional interchange map: within the 25500 series at 44.45 mm bore, the 82.931 mm OD and 23.812 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 19.2 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 570 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Inch tapered bearings are matched sets, not mix-and-match components: 25580 pairs the 25580 cone with the 25520 cup under the 25500-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.The SKF 25580/25520 is a 44.45×82.931×23.812 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "belt-driven fan and blower shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 44.45 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 25580 pair heats, loses setting control and smears the roller-rib contact.", "The 25500-series inch series at 44.45 mm bore (82.931×23.812 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one 25580 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Setting is a design value, not an assembly feel: excessive preload in the 25580 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 99.1/106 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 25580 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 25580/25520 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 25580 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 25500-series code marks the dimensional series. The metric dimensions 44.45×82.931×23.812 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 25580 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (25500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 25580 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 25580 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 25580 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 25580?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 23.812 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "25580-25520-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 44.45×82.931×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25580-25520", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "25580-25520" ], "locale_variants": {} }, { "sku": "25580-25522", "brand": "SKF", "manufacturer_designation": "SKF 25580/25522", "series": "25500-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 82.931, "B_mm": 26.988, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 99.1, "static_load_kN": 106, "fatigue_load_limit_kN": 11.8, "max_rpm": 8000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 8000, "weight_g": 610, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Mounting practice for 25580: the rotating cone takes the interference fit (k5 on a 44.45 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Journal and housing interface: the 44.45 mm bore takes a k5 shaft seat (upper deviation ~0.089 mm for this diameter range) and the 82.931 mm outside diameter pairs with an H7 housing bore tolerance band of 82.931.000/82.951 mm; the 26.988 mm width defines the shoulder depth, and the 610 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Cone-and-cup identity in 25580: the leading 25580 reference identifies the inner ring, rollers and cage; the trailing 25522 reference identifies the outer ring. The 25500-series series lists alternative cups for the same cone, each producing a different 82.931 mm OD or 26.988 mm width — hence a different SKU even though the bore stays at 44.45 mm.For a 44.45 mm shaft carrying combined load, SKF lists 25580 under catalogue execution SKF 25580/25522: one open single-row tapered roller bearing in the inch 25500-series.Reading the designation: 25580 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 25500-series code identifies the dimensional series. The 44.45 mm bore, 82.931 mm OD and 26.988 mm width are the metric equivalents of the inch boundary dimensions. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 99.1 kN and C0 106 kN, the 25580 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 8,000 r/min.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 44.45 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 25580 pair heats, loses setting control and smears the roller-rib contact.", "The 25500-series inch series at 44.45 mm bore (82.931×26.988 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 25580 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "A single 25580 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Catalogue reference speed and limiting speed are different limits: the 6,700 r/min reference is a thermal criterion under load, while the 8,000 r/min limiting value is the mechanical ceiling — observe both.", "The 99.1/106 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 25580 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 25580/25522 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 25580 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 25580 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 25580?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 26.988 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 25580 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 25580?", "a": "The SKF 25580/25522 is a single-row tapered roller bearing with 44.45 mm bore, 82.931 mm outer diameter and 26.988 mm width (1.75 × 3.265 × 1.063 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 99.1 kN, C0 106 kN, fatigue load limit Pu 11.8 kN, reference speed 6,700 r/min, limiting speed 8,000 r/min, mass about 610 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 25580 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 25500-series code marks the dimensional series. The metric dimensions 44.45×82.931×26.988 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "25580-25520-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25580-25522", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "25580-25522" ], "locale_variants": {} }, { "sku": "25580-25523", "brand": "SKF", "manufacturer_designation": "SKF 25580/25523", "series": "25500-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 82.931, "B_mm": 26.988, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 99.1, "static_load_kN": 106, "fatigue_load_limit_kN": 11.8, "max_rpm": 8000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 8000, "weight_g": 610, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. At 6,700 r/min reference speed the 19.2 mm-section 25580 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 8,000 r/min as the mechanical ceiling. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 25580 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Operating context for the 44.45 mm bore: a shaft of this diameter in the medium-bore band typically runs between 35560 and 53340 r/min in real machinery, and the 82.931 mm outside diameter places the housing shoulder at 91 mm outer abutment; the 26.988 mm width and 610 g mass together set the shaft critical speed and the housing resonance check for this 25500-series envelope. Two catalogue entries share the 25580 cone but use different cups; this one, 25580, takes the 25523 cup and is ground for the resulting 82.931 mm OD / 26.988 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.In SKF catalogue PUB BU/P1 17000, 25580 appears as SKF 25580/25523: an open, single-row tapered roller bearing in the 25500-series, supplied with a pressed-steel cage as standard.The 25500-series series assigns 44.45 mm bore, 82.931 mm OD and 26.988 mm width to 25580; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 44.45 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 25580 pair heats, loses setting control and smears the roller-rib contact.", "The 25500-series inch series at 44.45 mm bore (82.931×26.988 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 25580 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 25580 mounting error.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 82.931 mm cup race release as noise within the first running hours.", "The 99.1/106 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 25580 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 25580/25523 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in 25580 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (25500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 25580 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 25580 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 25580 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 25580?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 26.988 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 25580 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "25580-25520-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25580-25523", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "25580-25523" ], "locale_variants": {} }, { "sku": "HM803149-110", "brand": "SKF", "manufacturer_designation": "SKF HM 803149/110", "series": "HM803000-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 88.9, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 116, "static_load_kN": 127, "fatigue_load_limit_kN": 14.6, "max_rpm": 7500, "reference_speed_rpm": 6000, "limiting_speed_rpm": 7500, "weight_g": 860, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF HM 803149/110 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 44.45 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.Reading the designation: HM803149 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the HM803000-series code identifies the dimensional series. The 44.45 mm bore, 88.9 mm OD and 30.162 mm width are the metric equivalents of the inch boundary dimensions. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. The 14.6 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.09 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Because the contact line is tapered, one HM803149 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 44.45 mm shaft typically takes a k5 seat with an H7 housing bore. Operating context for the 44.45 mm bore: a shaft of this diameter in the medium-bore band typically runs between 35560 and 53340 r/min in real machinery, and the 88.9 mm outside diameter places the housing shoulder at 97 mm outer abutment; the 30.162 mm width and 860 g mass together set the shaft critical speed and the housing resonance check for this HM800-series envelope. Within the HM803000-series tables, HM 803149 appears in several rows because SKF lists multiple cup options for the same cone. HM803149 is the 110 variant, with 88.9 mm OD and 30.162 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "belt-driven fan and blower shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "On this 44.45 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight HM803149 pair heats, loses setting control and smears the roller-rib contact.", "The HM803000-series inch series at 44.45 mm bore (88.9×30.162 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the HM803149 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "A single HM803149 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 116/127 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM803149 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 803149/110 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of HM803149?", "a": "The SKF HM 803149/110 is a single-row tapered roller bearing with 44.45 mm bore, 88.9 mm outer diameter and 30.162 mm width (1.75 × 3.5 × 1.187 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 116 kN, C0 127 kN, fatigue load limit Pu 14.6 kN, reference speed 6,000 r/min, limiting speed 7,500 r/min, mass about 860 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM803149 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM803000-series code marks the dimensional series. The metric dimensions 44.45×88.9×30.162 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM803149 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM803000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single HM803149 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HM803149 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM803149 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "HM803149-HM803110", "equiv_brand": "NTN", "level": "partial", "note": "Same 44.45×88.9×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "HM803149-110", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM803149-110" ], "locale_variants": {} }, { "sku": "3782-3720", "brand": "SKF", "manufacturer_designation": "SKF 3782/3720", "series": "3700-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 93.264, "B_mm": 30.163, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 134, "static_load_kN": 146, "fatigue_load_limit_kN": 17, "max_rpm": 7000, "reference_speed_rpm": 5600, "limiting_speed_rpm": 7000, "weight_g": 980, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 3782/3720 is a 44.45×93.264×30.163 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.Numbering ties the bearing to its inch-series envelope: 3782 means a cone and cup matched pair in the 3700-series series — which is why the 44.45×93.264×30.163 mm outline swaps dimensionally with other inch-series bearings of the same code. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 134 kN and C0 146 kN, the 3782 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 7,000 r/min. Fit selection follows the rotating ring — interference on a rotating cone — and two 3782 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Operating context for the 44.45 mm bore: a shaft of this diameter in the medium-bore band typically runs between 35560 and 53340 r/min in real machinery, and the 93.264 mm outside diameter places the housing shoulder at 101 mm outer abutment; the 30.163 mm width and 980 g mass together set the shaft critical speed and the housing resonance check for this 37800-series envelope. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 3782 the 3782 cone contributes the 44.45 mm bore and roller set, the 3720 cup contributes the 93.264 mm OD raceway, and the assembled 30.163 mm width is the catalogue value.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 44.45 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 3782 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 44.45 mm bore (93.264×30.163 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 3782 mounting error.", "Setting is a design value, not an assembly feel: excessive preload in the 3782 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The 3782 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 134/146 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 3782 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 3782/3720 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 3782?", "a": "The SKF 3782/3720 is a single-row tapered roller bearing with 44.45 mm bore, 93.264 mm outer diameter and 30.163 mm width (1.75 × 3.672 × 1.188 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 134 kN, C0 146 kN, fatigue load limit Pu 17 kN, reference speed 5,600 r/min, limiting speed 7,000 r/min, mass about 980 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 3782 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 3700-series code marks the dimensional series. The metric dimensions 44.45×93.264×30.163 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 3782 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (3700-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 3782 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 3782 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 3782 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "3782-3720-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 44.45×93.264×30.163 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "3782-3720", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "3782-3720" ], "locale_variants": {} }, { "sku": "53178-53377", "brand": "SKF", "manufacturer_designation": "SKF 53178/53377", "series": "53000-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 95.25, "B_mm": 30.958, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 108, "static_load_kN": 96.5, "fatigue_load_limit_kN": 11.4, "max_rpm": 7000, "reference_speed_rpm": 5300, "limiting_speed_rpm": 7000, "weight_g": 930, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Fit selection follows the rotating ring — interference on a rotating cone — and two 53178 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Load system: the 108 kN basic dynamic rating C and 96.5 kN static rating C0 give a C0/C balance of 0.89, and dividing C by the 44.45 mm bore yields 2.43 kN per millimetre of journal — a density metric that compares across families; the 11.4 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 44.45 mm shaft carrying variable duty. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 53178 the 53178 cone contributes the 44.45 mm bore and roller set, the 53377 cup contributes the 95.25 mm OD raceway, and the assembled 30.958 mm width is the catalogue value.For a 44.45 mm shaft carrying combined load, SKF lists 53178 under catalogue execution SKF 53178/53377: one open single-row tapered roller bearing in the inch 53000-series.The 53000-series series assigns 44.45 mm bore, 95.25 mm OD and 30.958 mm width to 53178; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 11.4 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 0.89 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 44.45 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 53178 pair heats, loses setting control and smears the roller-rib contact.", "The 53000-series inch series at 44.45 mm bore (95.25×30.958 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one 53178 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 53178 mounting error.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 108/96.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 53178 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 53178/53377 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 53178 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 53178 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 53178?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 30.958 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 53178 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 53178?", "a": "The SKF 53178/53377 is a single-row tapered roller bearing with 44.45 mm bore, 95.25 mm outer diameter and 30.958 mm width (1.75 × 3.75 × 1.219 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 108 kN, C0 96.5 kN, fatigue load limit Pu 11.4 kN, reference speed 5,300 r/min, limiting speed 7,000 r/min, mass about 930 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 53178 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 53000-series code marks the dimensional series. The metric dimensions 44.45×95.25×30.958 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "53178-53377", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "53178-53377" ], "locale_variants": {} }, { "sku": "HM903249-210", "brand": "SKF", "manufacturer_designation": "SKF HM 903249/210", "series": "HM903200-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 95.25, "B_mm": 30.958, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 124, "static_load_kN": 122, "fatigue_load_limit_kN": 14, "max_rpm": 7000, "reference_speed_rpm": 5300, "limiting_speed_rpm": 7000, "weight_g": 1000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Housing and abutment design flows from the cup: in HM903249 the 210 cup fixes the 95.25 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the HM 903249 cone determines the 44.45 mm shaft interface; the 30.958 mm width is the assembled pair value.HM903249 is a single-row tapered roller bearing in the HM903200-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.The HM903200-series series assigns 44.45 mm bore, 95.25 mm OD and 30.958 mm width to HM903249; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. In SKF suffix language a bare HM903249 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Catalogue mass 1000 g for the 44.45×95.25×30.958 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Because the contact line is tapered, one HM903249 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 44.45 mm shaft typically takes a k5 seat with an H7 housing bore. Journal and housing interface: the 44.45 mm bore takes a k5 shaft seat (upper deviation ~0.089 mm for this diameter range) and the 95.25 mm outside diameter pairs with an H7 housing bore tolerance band of 95.25.000/95.270 mm; the 30.958 mm width defines the shoulder depth, and the 1000 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "On this 44.45 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight HM903249 pair heats, loses setting control and smears the roller-rib contact.", "The HM903200-series inch series at 44.45 mm bore (95.25×30.958 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common HM903249 mounting error.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common HM903249 mounting error.", "Shaft and housing fillets must clear the bearing chamfer so the 30.958 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 124/122 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM903249 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 903249/210 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is HM903249 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM903249?", "a": "The SKF HM 903249/210 is a single-row tapered roller bearing with 44.45 mm bore, 95.25 mm outer diameter and 30.958 mm width (1.75 × 3.75 × 1.219 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 124 kN, C0 122 kN, fatigue load limit Pu 14 kN, reference speed 5,300 r/min, limiting speed 7,000 r/min, mass about 1000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM903249 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM903200-series code marks the dimensional series. The metric dimensions 44.45×95.25×30.958 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM903249 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM903200-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single HM903249 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "HM903249-HM903210", "equiv_brand": "NTN", "level": "partial", "note": "Same 44.45×95.25×30.958 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "HM903249-210", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM903249-210" ], "locale_variants": {} }, { "sku": "HM807040-010", "brand": "SKF", "manufacturer_designation": "SKF HM 807040/010", "series": "HM-807000-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 104.775, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 180, "static_load_kN": 204, "fatigue_load_limit_kN": 22.4, "max_rpm": 6300, "reference_speed_rpm": 5000, "limiting_speed_rpm": 6300, "weight_g": 1650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The cup reference 010 is structural, not a suffix: it identifies the outer ring that, combined with the HM 807040 cone, produces the 44.45/104.775/36.512 mm envelope catalogue-listed as HM807040. Quote the cup number in full when ordering — the HM-807000-series tables contain other cups that fit the same cone but change the bearing.HM807040 is a single-row tapered roller bearing in the HM-807000-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Digit by digit, HM807040 reads as cone reference / cup reference in the HM-807000-series inch series; the 44.45 mm bore, 104.775 mm OD and 36.512 mm width are the metric equivalents of the original inch boundary values. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 22.4 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.13 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. A single HM807040 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Speed envelope and thermal behaviour: at 5,000 r/min thermal reference, the 44.45 mm bore shaft runs at a dn of 222k, and the 30.2 mm section dissipates heat through the cup-to-housing contact path; the 6,300 r/min mechanical ceiling reflects cage strength, and the 1650 g spinning cone contributes gyroscopic moment under rapid speed reversal.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "machine-tool spindles" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "On this 44.45 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight HM807040 pair heats, loses setting control and smears the roller-rib contact.", "The HM-807000-series inch series at 44.45 mm bore (104.775×36.512 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HM807040 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Setting is a design value, not an assembly feel: excessive preload in the HM807040 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The 1650 g mass and 36.512 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of HM807040.", "The 180/204 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM807040 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 807040/010 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is HM807040 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM807040?", "a": "The SKF HM 807040/010 is a single-row tapered roller bearing with 44.45 mm bore, 104.775 mm outer diameter and 36.512 mm width (1.75 × 4.125 × 1.437 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 180 kN, C0 204 kN, fatigue load limit Pu 22.4 kN, reference speed 5,000 r/min, limiting speed 6,300 r/min, mass about 1650 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM807040 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM-807000-series code marks the dimensional series. The metric dimensions 44.45×104.775×36.512 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM807040 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM-807000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single HM807040 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "HM807040-HM807010", "equiv_brand": "NTN", "level": "partial", "note": "Same 44.45×104.775×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "HM807040-010", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM807040-010" ], "locale_variants": {} }, { "sku": "535-532X", "brand": "SKF", "manufacturer_designation": "SKF 535/532 X", "series": "535-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 107.95, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 183, "static_load_kN": 190, "fatigue_load_limit_kN": 21.6, "max_rpm": 6300, "reference_speed_rpm": 5300, "limiting_speed_rpm": 6300, "weight_g": 1700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Operating context for the 44.45 mm bore: a shaft of this diameter in the medium-bore band typically runs between 35560 and 53340 r/min in real machinery, and the 107.95 mm outside diameter places the housing shoulder at 116 mm outer abutment; the 36.512 mm width and 1700 g mass together set the shaft critical speed and the housing resonance check for this 53500-series envelope. Cup-side note for 532 X: the outer ring's rib profile and the 107.95 mm outside diameter are cup-specific within the 535-series tables, so substituting a different cup against the same 535 cone changes both the assembled 36.512 mm width and the axial free-play setting of the mounted pair.Ordering number SKF 535/532 X in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 44.45 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.The 535-series series assigns 44.45 mm bore, 107.95 mm OD and 36.512 mm width to 535; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Speed planning uses two different ceilings: 5,300 r/min thermal reference and 6,300 r/min mechanical limiting speed. For a 44.45 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 535 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 44.45 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 535 pair heats, loses setting control and smears the roller-rib contact.", "The 535-series inch series at 44.45 mm bore (107.95×36.512 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 535 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 535 mounting error.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 107.95 mm cup race release as noise within the first running hours.", "The 183/190 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 535 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 535/532 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 535?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 36.512 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 535 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 535?", "a": "The SKF 535/532 X is a single-row tapered roller bearing with 44.45 mm bore, 107.95 mm outer diameter and 36.512 mm width (1.75 × 4.25 × 1.437 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 183 kN, C0 190 kN, fatigue load limit Pu 21.6 kN, reference speed 5,300 r/min, limiting speed 6,300 r/min, mass about 1700 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 535 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 535-series code marks the dimensional series. The metric dimensions 44.45×107.95×36.512 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 535 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (535-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "535-532X", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "535-532X" ], "locale_variants": {} }, { "sku": "535-532A", "brand": "SKF", "manufacturer_designation": "SKF 535/532 A", "series": "535-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 111.125, "B_mm": 38.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 183, "static_load_kN": 190, "fatigue_load_limit_kN": 21.6, "max_rpm": 6300, "reference_speed_rpm": 5300, "limiting_speed_rpm": 6300, "weight_g": 1850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Operating context for the 44.45 mm bore: a shaft of this diameter in the medium-bore band typically runs between 35560 and 53340 r/min in real machinery, and the 111.125 mm outside diameter places the housing shoulder at 119 mm outer abutment; the 38.1 mm width and 1850 g mass together set the shaft critical speed and the housing resonance check for this 53500-series envelope. Cone versus cup responsibility in 535: the 535 cone carries the 44.45 mm bore, rollers and pressed-steel cage; the 532 A cup carries the 111.125 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.Ordering number SKF 535/532 A in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 44.45 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.The 535-series series assigns 44.45 mm bore, 111.125 mm OD and 38.1 mm width to 535; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Speed planning uses two different ceilings: 5,300 r/min thermal reference and 6,300 r/min mechanical limiting speed. For a 44.45 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 535 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 44.45 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 535 pair heats, loses setting control and smears the roller-rib contact.", "The 535-series inch series at 44.45 mm bore (111.125×38.1 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 535 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 535 mounting error.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 111.125 mm cup race release as noise within the first running hours.", "The 183/190 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 535 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 535/532 A designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 535?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 38.1 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 535 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 535?", "a": "The SKF 535/532 A is a single-row tapered roller bearing with 44.45 mm bore, 111.125 mm outer diameter and 38.1 mm width (1.75 × 4.375 × 1.5 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 183 kN, C0 190 kN, fatigue load limit Pu 21.6 kN, reference speed 5,300 r/min, limiting speed 6,300 r/min, mass about 1850 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 535 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 535-series code marks the dimensional series. The metric dimensions 44.45×111.125×38.1 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 535 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (535-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "535-532A", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "535-532A" ], "locale_variants": {} }, { "sku": "3586-3525", "brand": "SKF", "manufacturer_designation": "SKF 3586/3525", "series": "3500-series", "type": "tapered_roller", "d_mm": 45.237, "D_mm": 87.312, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 126, "static_load_kN": 132, "fatigue_load_limit_kN": 15, "max_rpm": 8000, "reference_speed_rpm": 6300, "limiting_speed_rpm": 8000, "weight_g": 780, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Housing and abutment design flows from the cup: in 3586 the 3525 cup fixes the 87.312 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the 3586 cone determines the 45.237 mm shaft interface; the 30.162 mm width is the assembled pair value.SKF 3586 (SKF 3586/3525) is the 3500-series tapered roller choice for a 45.237 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 87.312×30.162 mm envelope.Reading the designation: 3586 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 3500-series code identifies the dimensional series. The 45.237 mm bore, 87.312 mm OD and 30.162 mm width are the metric equivalents of the inch boundary dimensions. In SKF suffix language a bare 3586 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 15 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.05 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Fit selection follows the rotating ring — interference on a rotating cone — and two 3586 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Journal and housing interface: the 45.237 mm bore takes a k5 shaft seat (upper deviation ~0.090 mm for this diameter range) and the 87.312 mm outside diameter pairs with an H7 housing bore tolerance band of 87.312.000/87.332 mm; the 30.162 mm width defines the shoulder depth, and the 780 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "machine-tool spindles" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "On this 45.237 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 3586 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 45.237 mm bore (87.312×30.162 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "At the 126 kN rating of 3586, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 8,000 r/min speed end and heavier preload only where moment stiffness dominates.", "At the 126 kN rating of 3586, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 8,000 r/min speed end and heavier preload only where moment stiffness dominates.", "Open 3586 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 126/132 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 3586 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 3586/3525 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 3586 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 3586?", "a": "The SKF 3586/3525 is a single-row tapered roller bearing with 45.237 mm bore, 87.312 mm outer diameter and 30.162 mm width (1.781 × 3.437 × 1.187 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 126 kN, C0 132 kN, fatigue load limit Pu 15 kN, reference speed 6,300 r/min, limiting speed 8,000 r/min, mass about 780 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 3586 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 3500-series code marks the dimensional series. The metric dimensions 45.237×87.312×30.162 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 3586 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (3500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 3586 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "3586-3525-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 45.237×87.312×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "3586-3525", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "3586-3525" ], "locale_variants": {} }, { "sku": "LM102949-910", "brand": "SKF", "manufacturer_designation": "SKF LM 102949/910", "series": "LM102900-series", "type": "tapered_roller", "d_mm": 45.242, "D_mm": 73.431, "B_mm": 19.558, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 66, "static_load_kN": 75, "fatigue_load_limit_kN": 8.15, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500, "weight_g": 310, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (LM102900-series) ties the pair to a specific boundary plan. Dimensions 45.242×73.431×19.558 mm are the converted metric envelope. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 66 kN and C0 75 kN, the LM102949 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 8,500 r/min. Because the contact line is tapered, one LM102949 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 45.242 mm shaft typically takes a k5 seat with an H7 housing bore. Journal and housing interface: the 45.242 mm bore takes a k5 shaft seat (upper deviation ~0.090 mm for this diameter range) and the 73.431 mm outside diameter pairs with an H7 housing bore tolerance band of 73.431.000/73.451 mm; the 19.558 mm width defines the shoulder depth, and the 310 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Cone-and-cup identity in LM102949: the leading LM 102949 reference identifies the inner ring, rollers and cage; the trailing 910 reference identifies the outer ring. The LM102900-series series lists alternative cups for the same cone, each producing a different 73.431 mm OD or 19.558 mm width — hence a different SKU even though the bore stays at 45.242 mm.For a 45.242 mm shaft carrying combined load, SKF lists LM102949 under catalogue execution SKF LM 102949/910: one open single-row tapered roller bearing in the inch LM102900-series.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "machine-tool spindles" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 45.242 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM102949 pair heats, loses setting control and smears the roller-rib contact.", "The LM102900-series inch series at 45.242 mm bore (73.431×19.558 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common LM102949 mounting error.", "Setting is a design value, not an assembly feel: excessive preload in the LM102949 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 73.431 mm cup race release as noise within the first running hours.", "The 66/75 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM102949 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 102949/910 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the LM102949 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM102900-series code marks the dimensional series. The metric dimensions 45.242×73.431×19.558 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM102949 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM102900-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM102949 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM102949 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM102949 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM102949?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 19.558 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "LM102949-LM102910", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "LM102949-910", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM102949-910" ], "locale_variants": {} }, { "sku": "LM603049-011", "brand": "SKF", "manufacturer_designation": "SKF LM 603049/011", "series": "LM603000-series", "type": "tapered_roller", "d_mm": 45.242, "D_mm": 77.788, "B_mm": 19.842, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 66.8, "static_load_kN": 69.5, "fatigue_load_limit_kN": 7.65, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500, "weight_g": 370, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. At 7,000 r/min reference speed the 16.3 mm-section LM603049 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 8,500 r/min as the mechanical ceiling. Fit selection follows the rotating ring — interference on a rotating cone — and two LM603049 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Cross-section geometry: the 16.3 mm half-section ((77.788−45.242)/2) of this LM600-series unit places the roller large-end pitch diameter at roughly 61 mm, and the 19.842 mm axial width is split between cone (11 mm) and cup rib (9 mm) — a geometry that sets the contact angle and, with the 370 g rotating cone mass, the critical speed at which cage-roller imbalance begins. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in LM603049 the LM 603049 cone contributes the 45.242 mm bore and roller set, the 011 cup contributes the 77.788 mm OD raceway, and the assembled 19.842 mm width is the catalogue value.In SKF catalogue PUB BU/P1 17000, LM603049 appears as SKF LM 603049/011: an open, single-row tapered roller bearing in the LM603000-series, supplied with a pressed-steel cage as standard.Reading the designation: LM603049 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the LM603000-series code identifies the dimensional series. The 45.242 mm bore, 77.788 mm OD and 19.842 mm width are the metric equivalents of the inch boundary dimensions.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 45.242 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM603049 pair heats, loses setting control and smears the roller-rib contact.", "The LM603000-series inch series at 45.242 mm bore (77.788×19.842 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the LM603049 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Do not mix brands or executions inside one LM603049 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 66.8/69.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM603049 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 603049/011 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in LM603049 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM603000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM603049 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM603049 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM603049 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM603049?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 19.842 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM603049 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "LM603049-LM603011", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "LM603049-011", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM603049-011" ], "locale_variants": {} }, { "sku": "LM603049-011AA", "brand": "SKF", "manufacturer_designation": "SKF LM 603049/011 AA", "series": "LM603000-series", "type": "tapered_roller", "d_mm": 45.242, "D_mm": 77.788, "B_mm": 19.842, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 66.8, "static_load_kN": 69.5, "fatigue_load_limit_kN": 7.65, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500, "weight_g": 370, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " In SKF suffix language a bare LM603049 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 7,000 r/min reference speed the 16.3 mm-section LM603049 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 8,500 r/min as the mechanical ceiling. Fit selection follows the rotating ring — interference on a rotating cone — and two LM603049 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Cross-section geometry: the 16.3 mm half-section ((77.788−45.242)/2) of this LM600-series unit places the roller large-end pitch diameter at roughly 61 mm, and the 19.842 mm axial width is split between cone (11 mm) and cup rib (9 mm) — a geometry that sets the contact angle and, with the 370 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Why the cup reference matters here: in the LM603000-series tables the LM 603049 cone appears against several cup options. LM603049 is the pairing with 011 AA, and that choice — not the cone — fixes the 77.788 mm OD, the raceway track position and the 19.842 mm assembled width.In SKF catalogue PUB BU/P1 17000, LM603049 appears as SKF LM 603049/011 AA: an open, single-row tapered roller bearing in the LM603000-series, supplied with a pressed-steel cage as standard.Reading the designation: LM603049 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the LM603000-series code identifies the dimensional series. The 45.242 mm bore, 77.788 mm OD and 19.842 mm width are the metric equivalents of the inch boundary dimensions.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "On this 45.242 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM603049 pair heats, loses setting control and smears the roller-rib contact.", "The LM603000-series inch series at 45.242 mm bore (77.788×19.842 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the LM603049 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Do not mix brands or executions inside one LM603049 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 66.8/69.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM603049 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 603049/011 AA designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in LM603049 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM603000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM603049 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM603049 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM603049 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM603049?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 19.842 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM603049 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "LM603049-LM603011", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "LM603049-011AA", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM603049-011AA" ], "locale_variants": {} }, { "sku": "LM603049-012", "brand": "SKF", "manufacturer_designation": "SKF LM 603049/012", "series": "LM603000-series", "type": "tapered_roller", "d_mm": 45.242, "D_mm": 77.788, "B_mm": 21.43, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 66.8, "static_load_kN": 69.5, "fatigue_load_limit_kN": 7.65, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500, "weight_g": 390, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " In SKF suffix language a bare LM603049 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 7,000 r/min reference speed the 16.3 mm-section LM603049 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 8,500 r/min as the mechanical ceiling. Fit selection follows the rotating ring — interference on a rotating cone — and two LM603049 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Cross-section geometry: the 16.3 mm half-section ((77.788−45.242)/2) of this LM600-series unit places the roller large-end pitch diameter at roughly 61 mm, and the 21.43 mm axial width is split between cone (12 mm) and cup rib (10 mm) — a geometry that sets the contact angle and, with the 390 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Inch tapered bearings are matched sets, not mix-and-match components: LM603049 pairs the LM 603049 cone with the 012 cup under the LM603000-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.In SKF catalogue PUB BU/P1 17000, LM603049 appears as SKF LM 603049/012: an open, single-row tapered roller bearing in the LM603000-series, supplied with a pressed-steel cage as standard.Reading the designation: LM603049 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the LM603000-series code identifies the dimensional series. The 45.242 mm bore, 77.788 mm OD and 21.43 mm width are the metric equivalents of the inch boundary dimensions.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "On this 45.242 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM603049 pair heats, loses setting control and smears the roller-rib contact.", "The LM603000-series inch series at 45.242 mm bore (77.788×21.43 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the LM603049 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Do not mix brands or executions inside one LM603049 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 66.8/69.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM603049 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 603049/012 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in LM603049 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM603000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM603049 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM603049 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM603049 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM603049?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 21.43 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM603049 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "LM603049-LM603011", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "LM603049-012", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM603049-012" ], "locale_variants": {} }, { "sku": "25590-25520", "brand": "SKF", "manufacturer_designation": "SKF 25590/25520", "series": "25500-series", "type": "tapered_roller", "d_mm": 45.618, "D_mm": 82.931, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 99.1, "static_load_kN": 106, "fatigue_load_limit_kN": 11.8, "max_rpm": 8000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 8000, "weight_g": 550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Within the 25500-series tables, 25590 appears in several rows because SKF lists multiple cup options for the same cone. 25590 is the 25520 variant, with 82.931 mm OD and 23.812 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.In SKF catalogue PUB BU/P1 17000, 25590 appears as SKF 25590/25520: an open, single-row tapered roller bearing in the 25500-series, supplied with a pressed-steel cage as standard.Numbering ties the bearing to its inch-series envelope: 25590 means a cone and cup matched pair in the 25500-series series — which is why the 45.618×82.931×23.812 mm outline swaps dimensionally with other inch-series bearings of the same code. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Speed planning uses two different ceilings: 6,700 r/min thermal reference and 8,000 r/min mechanical limiting speed. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 25590 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Speed envelope and thermal behaviour: at 6,700 r/min thermal reference, the 45.618 mm bore shaft runs at a dn of 306k, and the 18.7 mm section dissipates heat through the cup-to-housing contact path; the 8,000 r/min mechanical ceiling reflects cage strength, and the 550 g spinning cone contributes gyroscopic moment under rapid speed reversal.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "On this 45.618 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 25590 pair heats, loses setting control and smears the roller-rib contact.", "The 25500-series inch series at 45.618 mm bore (82.931×23.812 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 25590 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 25590 mounting error.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 99.1/106 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 25590 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 25590/25520 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 25590 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 25590?", "a": "The SKF 25590/25520 is a single-row tapered roller bearing with 45.618 mm bore, 82.931 mm outer diameter and 23.812 mm width (1.796 × 3.265 × 0.937 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 99.1 kN, C0 106 kN, fatigue load limit Pu 11.8 kN, reference speed 6,700 r/min, limiting speed 8,000 r/min, mass about 550 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 25590 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 25500-series code marks the dimensional series. The metric dimensions 45.618×82.931×23.812 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 25590 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (25500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 25590 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "25590-25519", "equiv_brand": "NTN", "level": "partial", "note": "Same 45.618×82.931×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25590-25520-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 45.618×82.931×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25590-25522-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 45.618×82.931×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25590-25526", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25590-25520", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "25590-25520" ], "locale_variants": {} }, { "sku": "25590-25523", "brand": "SKF", "manufacturer_designation": "SKF 25590/25523", "series": "25500-series", "type": "tapered_roller", "d_mm": 45.618, "D_mm": 82.931, "B_mm": 26.988, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 99.1, "static_load_kN": 106, "fatigue_load_limit_kN": 11.8, "max_rpm": 8000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 8000, "weight_g": 590, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " In SKF suffix language a bare 25590 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 1.07 (static 106 kN against dynamic 99.1 kN), typical of a tapered roller sized for axial capacity, and the 11.8 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. A single 25590 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Dimensional interchange map: within the 25500 series at 45.618 mm bore, the 82.931 mm OD and 26.988 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 18.7 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 590 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Two catalogue entries share the 25590 cone but use different cups; this one, 25590, takes the 25523 cup and is ground for the resulting 82.931 mm OD / 26.988 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.SKF 25590 (SKF 25590/25523) is the 25500-series tapered roller choice for a 45.618 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 82.931×26.988 mm envelope.In SKF inch-series tables 25590 sits at 45.618 mm bore (1.796 in) with a 82.931 mm cup OD and 26.988 mm total width — dimensions that trace back to the original Timken boundary plan for the 25500-series family.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "On this 45.618 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 25590 pair heats, loses setting control and smears the roller-rib contact.", "The 25500-series inch series at 45.618 mm bore (82.931×26.988 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 25590 mounting error.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 25590 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Catalogue reference speed and limiting speed are different limits: the 6,700 r/min reference is a thermal criterion under load, while the 8,000 r/min limiting value is the mechanical ceiling — observe both.", "The 99.1/106 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 25590 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 25590/25523 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in 25590 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (25500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 25590 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 25590 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 25590 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 25590?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 26.988 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 25590 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "25590-25519", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25590-25520-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25590-25522-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25590-25526", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25590-25523", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "25590-25523" ], "locale_variants": {} }, { "sku": "25590-25522", "brand": "SKF", "manufacturer_designation": "SKF 25590/25522", "series": "25500-series", "type": "tapered_roller", "d_mm": 45.618, "D_mm": 83.058, "B_mm": 23.876, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 99.1, "static_load_kN": 106, "fatigue_load_limit_kN": 11.8, "max_rpm": 8000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 8000, "weight_g": 550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " For a 45.618 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 25590 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Cross-section geometry: the 18.7 mm half-section ((83.058−45.618)/2) of this 25500-series unit places the roller large-end pitch diameter at roughly 64 mm, and the 23.876 mm axial width is split between cone (13 mm) and cup rib (11 mm) — a geometry that sets the contact angle and, with the 550 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Cone-and-cup identity in 25590: the leading 25590 reference identifies the inner ring, rollers and cage; the trailing 25522 reference identifies the outer ring. The 25500-series series lists alternative cups for the same cone, each producing a different 83.058 mm OD or 23.876 mm width — hence a different SKU even though the bore stays at 45.618 mm.25590 is a single-row tapered roller bearing in the 25500-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (25500-series) ties the pair to a specific boundary plan. Dimensions 45.618×83.058×23.876 mm are the converted metric envelope. In SKF suffix language a bare 25590 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Catalogue mass 550 g for the 45.618×83.058×23.876 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "On this 45.618 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 25590 pair heats, loses setting control and smears the roller-rib contact.", "The 25500-series inch series at 45.618 mm bore (83.058×23.876 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 25590 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "At the 99.1 kN rating of 25590, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 8,000 r/min speed end and heavier preload only where moment stiffness dominates.", "Open 25590 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 99.1/106 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 25590 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 25590/25522 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 25590 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 25590 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 25590?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 23.876 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 25590 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 25590?", "a": "The SKF 25590/25522 is a single-row tapered roller bearing with 45.618 mm bore, 83.058 mm outer diameter and 23.876 mm width (1.796 × 3.27 × 0.94 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 99.1 kN, C0 106 kN, fatigue load limit Pu 11.8 kN, reference speed 6,700 r/min, limiting speed 8,000 r/min, mass about 550 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 25590 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 25500-series code marks the dimensional series. The metric dimensions 45.618×83.058×23.876 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "25590-25519", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25590-25520-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 45.618×83.058×23.876 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25590-25522-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 45.618×83.058×23.876 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25590-25526", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25590-25522", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "25590-25522" ], "locale_variants": {} }, { "sku": "LM503349A-310", "brand": "SKF", "manufacturer_designation": "SKF LM 503349 A/310", "series": "LM503300-series", "type": "tapered_roller", "d_mm": 46, "D_mm": 75, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 62.1, "static_load_kN": 71, "fatigue_load_limit_kN": 7.65, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 46 mm shaft carrying combined load, SKF lists LM503349A under catalogue execution SKF LM 503349 A/310: one open single-row tapered roller bearing in the inch LM503300-series.The LM503300-series series assigns 46 mm bore, 75 mm OD and 18 mm width to LM503349A; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. In SKF suffix language a bare LM503349A is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Speed planning uses two different ceilings: 7,000 r/min thermal reference and 8,500 r/min mechanical limiting speed. Specify pairs rather than single units wherever thrust reverses: the tapered contact of LM503349A generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Speed envelope and thermal behaviour: at 7,000 r/min thermal reference, the 46 mm bore shaft runs at a dn of 322k, and the 14.5 mm section dissipates heat through the cup-to-housing contact path; the 8,500 r/min mechanical ceiling reflects cage strength, and the 300 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cup-side note for 310: the outer ring's rib profile and the 75 mm outside diameter are cup-specific within the LM503300-series tables, so substituting a different cup against the same LM 503349 A cone changes both the assembled 18 mm width and the axial free-play setting of the mounted pair.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "On this 46 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM503349A pair heats, loses setting control and smears the roller-rib contact.", "The LM503300-series inch series at 46 mm bore (75×18 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 62.1 kN rating of LM503349A, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 8,500 r/min speed end and heavier preload only where moment stiffness dominates.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of LM503349A pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The 300 g mass and 18 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of LM503349A.", "The 62.1/71 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM503349A (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 503349 A/310 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of LM503349A?", "a": "The SKF LM 503349 A/310 is a single-row tapered roller bearing with 46 mm bore, 75 mm outer diameter and 18 mm width (1.811 × 2.953 × 0.709 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 62.1 kN, C0 71 kN, fatigue load limit Pu 7.65 kN, reference speed 7,000 r/min, limiting speed 8,500 r/min, mass about 300 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM503349A inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM503300-series code marks the dimensional series. The metric dimensions 46×75×18 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM503349A mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM503300-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM503349A take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM503349A compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM503349A position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "LM503349A-LM503310", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "LM503349A-310", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM503349A-310" ], "locale_variants": {} }, { "sku": "LM503349-310", "brand": "SKF", "manufacturer_designation": "SKF LM 503349/310", "series": "LM503300-series", "type": "tapered_roller", "d_mm": 46, "D_mm": 75, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 62.1, "static_load_kN": 71, "fatigue_load_limit_kN": 7.65, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Why the cup reference matters here: in the LM503300-series tables the LM 503349 cone appears against several cup options. LM503349 is the pairing with 310, and that choice — not the cone — fixes the 75 mm OD, the raceway track position and the 18 mm assembled width.SKF LM503349 (SKF LM 503349/310) is the LM503300-series tapered roller choice for a 46 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 75×18 mm envelope.Numbering ties the bearing to its inch-series envelope: LM503349 means a cone and cup matched pair in the LM503300-series series — which is why the 46×75×18 mm outline swaps dimensionally with other inch-series bearings of the same code. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. At 7,000 r/min reference speed the 14.5 mm-section LM503349 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 8,500 r/min as the mechanical ceiling. Fit selection follows the rotating ring — interference on a rotating cone — and two LM503349 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Load system: the 62.1 kN basic dynamic rating C and 71 kN static rating C0 give a C0/C balance of 1.14, and dividing C by the 46 mm bore yields 1.35 kN per millimetre of journal — a density metric that compares across families; the 7.65 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 46 mm shaft carrying variable duty.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "belt-driven fan and blower shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "On this 46 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM503349 pair heats, loses setting control and smears the roller-rib contact.", "The LM503300-series inch series at 46 mm bore (75×18 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single LM503349 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "At the 62.1 kN rating of LM503349, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 8,500 r/min speed end and heavier preload only where moment stiffness dominates.", "Open LM503349 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 62.1/71 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM503349 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 503349/310 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is LM503349 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM503349?", "a": "The SKF LM 503349/310 is a single-row tapered roller bearing with 46 mm bore, 75 mm outer diameter and 18 mm width (1.811 × 2.953 × 0.709 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 62.1 kN, C0 71 kN, fatigue load limit Pu 7.65 kN, reference speed 7,000 r/min, limiting speed 8,500 r/min, mass about 300 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM503349 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM503300-series code marks the dimensional series. The metric dimensions 46×75×18 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM503349 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM503300-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM503349 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "LM503349-310", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM503349-310" ], "locale_variants": {} }, { "sku": "18690-18620", "brand": "SKF", "manufacturer_designation": "SKF 18690/18620", "series": "18600-series", "type": "tapered_roller", "d_mm": 46.038, "D_mm": 79.375, "B_mm": 17.462, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 61.1, "static_load_kN": 62, "fatigue_load_limit_kN": 6.8, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500, "weight_g": 330, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Dimensional interchange map: within the 18600 series at 46.038 mm bore, the 79.375 mm OD and 17.462 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 16.7 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 330 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 18690 the 18690 cone contributes the 46.038 mm bore and roller set, the 18620 cup contributes the 79.375 mm OD raceway, and the assembled 17.462 mm width is the catalogue value.SKF 18690/18620 belongs to the SKF single-row tapered roller range — the 46.038 mm bore entry in the inch 18600-series, dimensioned 79.375 mm OD and 17.462 mm wide.The 18600-series series assigns 46.038 mm bore, 79.375 mm OD and 17.462 mm width to 18690; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Speed planning uses two different ceilings: 7,000 r/min thermal reference and 8,500 r/min mechanical limiting speed. A single 18690 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "On this 46.038 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 18690 pair heats, loses setting control and smears the roller-rib contact.", "The 18600-series inch series at 46.038 mm bore (79.375×17.462 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 18690 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 18690 mounting error.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 61.1/62 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 18690 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 18690/18620 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 18690?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 17.462 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 18690 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 18690?", "a": "The SKF 18690/18620 is a single-row tapered roller bearing with 46.038 mm bore, 79.375 mm outer diameter and 17.462 mm width (1.813 × 3.125 × 0.687 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 61.1 kN, C0 62 kN, fatigue load limit Pu 6.8 kN, reference speed 7,000 r/min, limiting speed 8,500 r/min, mass about 330 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 18690 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 18600-series code marks the dimensional series. The metric dimensions 46.038×79.375×17.462 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 18690 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (18600-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "18690-18620-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 46.038×79.375×17.462 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "18690-18620", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "18690-18620" ], "locale_variants": {} }, { "sku": "359S-354X", "brand": "SKF", "manufacturer_designation": "SKF 359 S/354 X", "series": "355-series", "type": "tapered_roller", "d_mm": 46.038, "D_mm": 85, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 87.3, "static_load_kN": 81.5, "fatigue_load_limit_kN": 9.3, "max_rpm": 8000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 8000, "weight_g": 490, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Specify pairs rather than single units wherever thrust reverses: the tapered contact of 359S generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Cross-section geometry: the 19.5 mm half-section ((85−46.038)/2) of this 35900-series unit places the roller large-end pitch diameter at roughly 65 mm, and the 20.638 mm axial width is split between cone (11 mm) and cup rib (9 mm) — a geometry that sets the contact angle and, with the 490 g rotating cone mass, the critical speed at which cage-roller imbalance begins. From a specification standpoint the 354 X cup is the controlling half of 359S for housing design — it sets the 85 mm OD and the outer abutment diameter — while the 359 S cone controls shaft fit at the 46.038 mm bore; the 20.638 mm width is the result of the two together.359S is a single-row tapered roller bearing in the 355-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Numbering ties the bearing to its inch-series envelope: 359S means a cone and cup matched pair in the 355-series series — which is why the 46.038×85×20.638 mm outline swaps dimensionally with other inch-series bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Catalogue mass 490 g for the 46.038×85×20.638 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "On this 46.038 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 359S pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 46.038 mm bore (85×20.638 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 359S pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "A single 359S cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Shaft and housing fillets must clear the bearing chamfer so the 20.638 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 87.3/81.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 359S (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 359 S/354 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 359S compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 359S position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 359S?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 20.638 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 359S interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 359S?", "a": "The SKF 359 S/354 X is a single-row tapered roller bearing with 46.038 mm bore, 85 mm outer diameter and 20.638 mm width (1.813 × 3.346 × 0.813 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 87.3 kN, C0 81.5 kN, fatigue load limit Pu 9.3 kN, reference speed 6,700 r/min, limiting speed 8,000 r/min, mass about 490 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 359S inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 355-series code marks the dimensional series. The metric dimensions 46.038×85×20.638 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "359S-352", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "359S-354X", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "359S-354X" ], "locale_variants": {} }, { "sku": "HM804846-810", "brand": "SKF", "manufacturer_designation": "SKF HM 804846/810", "series": "HM804800-series", "type": "tapered_roller", "d_mm": 46.038, "D_mm": 95.25, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 133, "static_load_kN": 146, "fatigue_load_limit_kN": 17.3, "max_rpm": 7000, "reference_speed_rpm": 5600, "limiting_speed_rpm": 7000, "weight_g": 990, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " At 5,600 r/min reference speed the 24.6 mm-section HM804846 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 7,000 r/min as the mechanical ceiling. Fit selection follows the rotating ring — interference on a rotating cone — and two HM804846 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Load system: the 133 kN basic dynamic rating C and 146 kN static rating C0 give a C0/C balance of 1.10, and dividing C by the 46.038 mm bore yields 2.89 kN per millimetre of journal — a density metric that compares across families; the 17.3 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 46.038 mm shaft carrying variable duty. Cup-side note for 810: the outer ring's rib profile and the 95.25 mm outside diameter are cup-specific within the HM804800-series tables, so substituting a different cup against the same HM 804846 cone changes both the assembled 30.162 mm width and the axial free-play setting of the mounted pair.Ordering number SKF HM 804846/810 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 46.038 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (HM804800-series) ties the pair to a specific boundary plan. Dimensions 46.038×95.25×30.162 mm are the converted metric envelope. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "On this 46.038 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight HM804846 pair heats, loses setting control and smears the roller-rib contact.", "The HM804800-series inch series at 46.038 mm bore (95.25×30.162 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the HM804846 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the HM804846 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The 990 g mass and 30.162 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of HM804846.", "The 133/146 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM804846 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 804846/810 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single HM804846 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HM804846 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM804846 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HM804846?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 30.162 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HM804846 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM804846?", "a": "The SKF HM 804846/810 is a single-row tapered roller bearing with 46.038 mm bore, 95.25 mm outer diameter and 30.162 mm width (1.813 × 3.75 × 1.187 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 133 kN, C0 146 kN, fatigue load limit Pu 17.3 kN, reference speed 5,600 r/min, limiting speed 7,000 r/min, mass about 990 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "HM804846-HM804810", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "HM804846-810", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM804846-810" ], "locale_variants": {} }, { "sku": "528R-522", "brand": "SKF", "manufacturer_designation": "SKF 528 R/522", "series": "525-series", "type": "tapered_roller", "d_mm": 46.038, "D_mm": 101.6, "B_mm": 34.925, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 184, "static_load_kN": 190, "fatigue_load_limit_kN": 21.6, "max_rpm": 6700, "reference_speed_rpm": 5600, "limiting_speed_rpm": 6700, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " With C 184 kN and C0 190 kN, the 528R pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 6,700 r/min. A single 528R locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Cross-section geometry: the 27.8 mm half-section ((101.6−46.038)/2) of this 52800-series unit places the roller large-end pitch diameter at roughly 73 mm, and the 34.925 mm axial width is split between cone (19 mm) and cup rib (16 mm) — a geometry that sets the contact angle and, with the 1300 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Within the 525-series tables, 528 R appears in several rows because SKF lists multiple cup options for the same cone. 528R is the 522 variant, with 101.6 mm OD and 34.925 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.Ordering number SKF 528 R/522 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 46.038 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.The 525-series series assigns 46.038 mm bore, 101.6 mm OD and 34.925 mm width to 528R; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. In SKF suffix language a bare 528R is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 46.038 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 528R pair heats, loses setting control and smears the roller-rib contact.", "The 525-series inch series at 46.038 mm bore (101.6×34.925 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 528R pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 528R pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Catalogue reference speed and limiting speed are different limits: the 5,600 r/min reference is a thermal criterion under load, while the 6,700 r/min limiting value is the mechanical ceiling — observe both.", "The 184/190 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 528R (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 528 R/522 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 528R take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 528R compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 528R position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 528R?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 34.925 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 528R interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 528R?", "a": "The SKF 528 R/522 is a single-row tapered roller bearing with 46.038 mm bore, 101.6 mm outer diameter and 34.925 mm width (1.813 × 4 × 1.375 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 184 kN, C0 190 kN, fatigue load limit Pu 21.6 kN, reference speed 5,600 r/min, limiting speed 6,700 r/min, mass about 1300 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "528R-522", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "528R-522" ], "locale_variants": {} }, { "sku": "65390-65320", "brand": "SKF", "manufacturer_designation": "SKF 65390/65320", "series": "65300-series", "type": "tapered_roller", "d_mm": 49.212, "D_mm": 114.3, "B_mm": 44.45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 226, "static_load_kN": 224, "fatigue_load_limit_kN": 25, "max_rpm": 6300, "reference_speed_rpm": 5000, "limiting_speed_rpm": 6300, "weight_g": 2200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. At 5,000 r/min reference speed the 32.5 mm-section 65390 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 6,300 r/min as the mechanical ceiling. A single 65390 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Load system: the 226 kN basic dynamic rating C and 224 kN static rating C0 give a C0/C balance of 0.99, and dividing C by the 49.212 mm bore yields 4.59 kN per millimetre of journal — a density metric that compares across families; the 25 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 49.212 mm shaft carrying variable duty. Two catalogue entries share the 65390 cone but use different cups; this one, 65390, takes the 65320 cup and is ground for the resulting 114.3 mm OD / 44.45 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.The SKF 65390/65320 is a 49.212×114.3×44.45 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.Reading the designation: 65390 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 65300-series code identifies the dimensional series. The 49.212 mm bore, 114.3 mm OD and 44.45 mm width are the metric equivalents of the inch boundary dimensions.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "On this 49.212 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 65390 pair heats, loses setting control and smears the roller-rib contact.", "The 65300-series inch series at 49.212 mm bore (114.3×44.45 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 65390 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Do not mix brands or executions inside one 65390 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The 65390 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 226/224 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 65390 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 65390/65320 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in 65390 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (65300-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 65390 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 65390 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 65390 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 65390?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 44.45 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 65390 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "65390-65320-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "65390-65320", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "65390-65320" ], "locale_variants": {} }, { "sku": "LM104949-911", "brand": "SKF", "manufacturer_designation": "SKF LM 104949/911", "series": "LM104900-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 82.55, "B_mm": 21.59, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 88.9, "static_load_kN": 100, "fatigue_load_limit_kN": 11, "max_rpm": 8000, "reference_speed_rpm": 6300, "limiting_speed_rpm": 8000, "weight_g": 430, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Inch tapered bearings are matched sets, not mix-and-match components: LM104949 pairs the LM 104949 cone with the 911 cup under the LM104900-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.SKF LM104949 (SKF LM 104949/911) is the LM104900-series tapered roller choice for a 50.8 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 82.55×21.59 mm envelope.Numbering ties the bearing to its inch-series envelope: LM104949 means a cone and cup matched pair in the LM104900-series series — which is why the 50.8×82.55×21.59 mm outline swaps dimensionally with other inch-series bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Catalogue mass 430 g for the 50.8×82.55×21.59 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. A single LM104949 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Operating context for the 50.8 mm bore: a shaft of this diameter in the medium-bore band typically runs between 40640 and 60960 r/min in real machinery, and the 82.55 mm outside diameter places the housing shoulder at 91 mm outer abutment; the 21.59 mm width and 430 g mass together set the shaft critical speed and the housing resonance check for this LM100-series envelope.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 50.8 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM104949 pair heats, loses setting control and smears the roller-rib contact.", "The LM104900-series inch series at 50.8 mm bore (82.55×21.59 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single LM104949 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the LM104949 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The LM104949 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 88.9/100 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM104949 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 104949/911 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is LM104949 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM104949?", "a": "The SKF LM 104949/911 is a single-row tapered roller bearing with 50.8 mm bore, 82.55 mm outer diameter and 21.59 mm width (2 × 3.25 × 0.85 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 88.9 kN, C0 100 kN, fatigue load limit Pu 11 kN, reference speed 6,300 r/min, limiting speed 8,000 r/min, mass about 430 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM104949 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM104900-series code marks the dimensional series. The metric dimensions 50.8×82.55×21.59 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM104949 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM104900-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM104949 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "LM104949-LM104911", "equiv_brand": "NTN", "level": "partial", "note": "Same 50.8×82.55×21.59 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "LM104949-911", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM104949-911" ], "locale_variants": {} }, { "sku": "18790-18720", "brand": "SKF", "manufacturer_designation": "SKF 18790/18720", "series": "18700-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 85, "B_mm": 17.462, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 62.1, "static_load_kN": 65.5, "fatigue_load_limit_kN": 7.2, "max_rpm": 8000, "reference_speed_rpm": 6300, "limiting_speed_rpm": 8000, "weight_g": 370, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The 17.1 mm radial section height ((85−50.8)/2) and 370 g catalogue mass frame a 50.8 mm bore bearing rated at 62.1 kN C — roughly 1.22 kN of dynamic capacity per millimetre of bore before application factors. A single 18790 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Journal and housing interface: the 50.8 mm bore takes a k5 shaft seat (upper deviation ~0.102 mm for this diameter range) and the 85 mm outside diameter pairs with an H7 housing bore tolerance band of 85.000/85.020 mm; the 17.462 mm width defines the shoulder depth, and the 370 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. From a specification standpoint the 18720 cup is the controlling half of 18790 for housing design — it sets the 85 mm OD and the outer abutment diameter — while the 18790 cone controls shaft fit at the 50.8 mm bore; the 17.462 mm width is the result of the two together.SKF 18790/18720 belongs to the SKF single-row tapered roller range — the 50.8 mm bore entry in the inch 18700-series, dimensioned 85 mm OD and 17.462 mm wide.The 18700-series series assigns 50.8 mm bore, 85 mm OD and 17.462 mm width to 18790; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "belt-driven fan and blower shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 50.8 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 18790 pair heats, loses setting control and smears the roller-rib contact.", "The 18700-series inch series at 50.8 mm bore (85×17.462 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 18790 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 18790 mounting error.", "Shaft and housing fillets must clear the bearing chamfer so the 17.462 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 62.1/65.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 18790 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 18790/18720 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 18790 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 18790 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 18790 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 18790?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 17.462 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 18790 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 18790?", "a": "The SKF 18790/18720 is a single-row tapered roller bearing with 50.8 mm bore, 85 mm outer diameter and 17.462 mm width (2 × 3.346 × 0.687 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 62.1 kN, C0 65.5 kN, fatigue load limit Pu 7.2 kN, reference speed 6,300 r/min, limiting speed 8,000 r/min, mass about 370 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "18790-18720-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 50.8×85×17.462 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "18790-18724", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "18790-18720", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "18790-18720" ], "locale_variants": {} }, { "sku": "368A-362A", "brand": "SKF", "manufacturer_designation": "SKF 368 A/362 A", "series": "365-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 88.9, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 94, "static_load_kN": 91.5, "fatigue_load_limit_kN": 10.4, "max_rpm": 7500, "reference_speed_rpm": 6300, "limiting_speed_rpm": 7500, "weight_g": 500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF inch-series tables 368A sits at 50.8 mm bore (2 in) with a 88.9 mm cup OD and 20.638 mm total width — dimensions that trace back to the original Timken boundary plan for the 365-series family. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 19.1 mm radial section height ((88.9−50.8)/2) and 500 g catalogue mass frame a 50.8 mm bore bearing rated at 94 kN C — roughly 1.85 kN of dynamic capacity per millimetre of bore before application factors. A single 368A locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Journal and housing interface: the 50.8 mm bore takes a k5 shaft seat (upper deviation ~0.102 mm for this diameter range) and the 88.9 mm outside diameter pairs with an H7 housing bore tolerance band of 88.9.000/88.920 mm; the 20.638 mm width defines the shoulder depth, and the 500 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Housing and abutment design flows from the cup: in 368A the 362 A cup fixes the 88.9 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the 368 A cone determines the 50.8 mm shaft interface; the 20.638 mm width is the assembled pair value.Ordering number SKF 368 A/362 A in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 50.8 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "On this 50.8 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 368A pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 50.8 mm bore (88.9×20.638 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "A single 368A cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 368A pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 94/91.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 368A (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 368 A/362 A designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 368A inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 365-series code marks the dimensional series. The metric dimensions 50.8×88.9×20.638 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 368A mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (365-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 368A take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 368A compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 368A position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 368A?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 20.638 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "368A-362", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "368A-362A", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "368A-362A" ], "locale_variants": {} }, { "sku": "368A-362X", "brand": "SKF", "manufacturer_designation": "SKF 368 A/362 X", "series": "365-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 90, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 94, "static_load_kN": 91.5, "fatigue_load_limit_kN": 10.4, "max_rpm": 7500, "reference_speed_rpm": 6300, "limiting_speed_rpm": 7500, "weight_g": 580, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " At 6,300 r/min reference speed the 19.6 mm-section 368A is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 7,500 r/min as the mechanical ceiling. For a 50.8 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 368A bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Load system: the 94 kN basic dynamic rating C and 91.5 kN static rating C0 give a C0/C balance of 0.97, and dividing C by the 50.8 mm bore yields 1.85 kN per millimetre of journal — a density metric that compares across families; the 10.4 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 50.8 mm shaft carrying variable duty. From a specification standpoint the 362 X cup is the controlling half of 368A for housing design — it sets the 90 mm OD and the outer abutment diameter — while the 368 A cone controls shaft fit at the 50.8 mm bore; the 25 mm width is the result of the two together.The SKF 368 A/362 X is a 50.8×90×25 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (365-series) ties the pair to a specific boundary plan. Dimensions 50.8×90×25 mm are the converted metric envelope. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "On this 50.8 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 368A pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 50.8 mm bore (90×25 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 368A rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 368A rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The 368A shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 94/91.5 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 368A (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 368 A/362 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 368A take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 368A compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 368A position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 368A?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 25 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 368A interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 368A?", "a": "The SKF 368 A/362 X is a single-row tapered roller bearing with 50.8 mm bore, 90 mm outer diameter and 25 mm width (2 × 3.543 × 0.984 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 94 kN, C0 91.5 kN, fatigue load limit Pu 10.4 kN, reference speed 6,300 r/min, limiting speed 7,500 r/min, mass about 580 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "368A-362", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "368A-362X", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "368A-362X" ], "locale_variants": {} }, { "sku": "3780-3720", "brand": "SKF", "manufacturer_designation": "SKF 3780/3720", "series": "3700-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 93.264, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 134, "static_load_kN": 146, "fatigue_load_limit_kN": 17, "max_rpm": 7000, "reference_speed_rpm": 5600, "limiting_speed_rpm": 7000, "weight_g": 870, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Dimensional interchange map: within the 37800 series at 50.8 mm bore, the 93.264 mm OD and 30.162 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 21.2 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 870 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 3780 the 3780 cone contributes the 50.8 mm bore and roller set, the 3720 cup contributes the 93.264 mm OD raceway, and the assembled 30.162 mm width is the catalogue value.For a 50.8 mm shaft carrying combined load, SKF lists 3780 under catalogue execution SKF 3780/3720: one open single-row tapered roller bearing in the inch 3700-series.Reading the designation: 3780 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 3700-series code identifies the dimensional series. The 50.8 mm bore, 93.264 mm OD and 30.162 mm width are the metric equivalents of the inch boundary dimensions. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 21.2 mm radial section height ((93.264−50.8)/2) and 870 g catalogue mass frame a 50.8 mm bore bearing rated at 134 kN C — roughly 2.64 kN of dynamic capacity per millimetre of bore before application factors. A single 3780 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "On this 50.8 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 3780 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 50.8 mm bore (93.264×30.162 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 3780 mounting error.", "At the 134 kN rating of 3780, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 7,000 r/min speed end and heavier preload only where moment stiffness dominates.", "The 3780 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 134/146 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 3780 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 3780/3720 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 3780?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 30.162 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 3780 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 3780?", "a": "The SKF 3780/3720 is a single-row tapered roller bearing with 50.8 mm bore, 93.264 mm outer diameter and 30.162 mm width (2 × 3.672 × 1.187 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 134 kN, C0 146 kN, fatigue load limit Pu 17 kN, reference speed 5,600 r/min, limiting speed 7,000 r/min, mass about 870 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 3780 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 3700-series code marks the dimensional series. The metric dimensions 50.8×93.264×30.162 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 3780 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (3700-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "3780-3720-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 50.8×93.264×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "3780-3726", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "3780-3732", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "3780-3720", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "3780-3720" ], "locale_variants": {} }, { "sku": "HM807046-010", "brand": "SKF", "manufacturer_designation": "SKF HM 807046/010", "series": "HM807000-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 104.775, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 180, "static_load_kN": 204, "fatigue_load_limit_kN": 22.4, "max_rpm": 6300, "reference_speed_rpm": 5000, "limiting_speed_rpm": 6300, "weight_g": 1500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Specify pairs rather than single units wherever thrust reverses: the tapered contact of HM807046 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Material and manufacturing detail: the 1500 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the HM800 ISO envelope, with the pressed-steel cage contributing roughly 45 g of the total; the 50.8 mm bore is ground to IT5 roundness and the 104.775 mm OD to IT5 cylindricity, and the 36.512 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Two catalogue entries share the HM 807046 cone but use different cups; this one, HM807046, takes the 010 cup and is ground for the resulting 104.775 mm OD / 36.512 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.For a 50.8 mm shaft carrying combined load, SKF lists HM807046 under catalogue execution SKF HM 807046/010: one open single-row tapered roller bearing in the inch HM807000-series.The HM807000-series series assigns 50.8 mm bore, 104.775 mm OD and 36.512 mm width to HM807046; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. At 5,000 r/min reference speed the 27.0 mm-section HM807046 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 6,300 r/min as the mechanical ceiling.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 50.8 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight HM807046 pair heats, loses setting control and smears the roller-rib contact.", "The HM807000-series inch series at 50.8 mm bore (104.775×36.512 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one HM807046 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HM807046 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Open HM807046 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 180/204 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM807046 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 807046/010 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does HM807046 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM807046 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HM807046?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 36.512 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HM807046 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM807046?", "a": "The SKF HM 807046/010 is a single-row tapered roller bearing with 50.8 mm bore, 104.775 mm outer diameter and 36.512 mm width (2 × 4.125 × 1.437 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 180 kN, C0 204 kN, fatigue load limit Pu 22.4 kN, reference speed 5,000 r/min, limiting speed 6,300 r/min, mass about 1500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM807046 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM807000-series code marks the dimensional series. The metric dimensions 50.8×104.775×36.512 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "HM807046-HM807010", "equiv_brand": "NTN", "level": "partial", "note": "Same 50.8×104.775×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "HM807046-010", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM807046-010" ], "locale_variants": {} }, { "sku": "4580-4535", "brand": "SKF", "manufacturer_designation": "SKF 4580/4535", "series": "4500-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 104.775, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 195, "static_load_kN": 224, "fatigue_load_limit_kN": 25, "max_rpm": 6300, "reference_speed_rpm": 5300, "limiting_speed_rpm": 6300, "weight_g": 1650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " A single 4580 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Dimensional interchange map: within the 45800 series at 50.8 mm bore, the 104.775 mm OD and 39.688 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 27.0 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 1650 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Cup-side note for 4535: the outer ring's rib profile and the 104.775 mm outside diameter are cup-specific within the 4500-series tables, so substituting a different cup against the same 4580 cone changes both the assembled 39.688 mm width and the axial free-play setting of the mounted pair.In SKF catalogue PUB BU/P1 17000, 4580 appears as SKF 4580/4535: an open, single-row tapered roller bearing in the 4500-series, supplied with a pressed-steel cage as standard.Digit by digit, 4580 reads as cone reference / cup reference in the 4500-series inch series; the 50.8 mm bore, 104.775 mm OD and 39.688 mm width are the metric equivalents of the original inch boundary values. In SKF suffix language a bare 4580 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 27.0 mm radial section height ((104.775−50.8)/2) and 1650 g catalogue mass frame a 50.8 mm bore bearing rated at 195 kN C — roughly 3.84 kN of dynamic capacity per millimetre of bore before application factors.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "On this 50.8 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 4580 pair heats, loses setting control and smears the roller-rib contact.", "The 4500-series inch series at 50.8 mm bore (104.775×39.688 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 195 kN rating of 4580, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 6,300 r/min speed end and heavier preload only where moment stiffness dominates.", "A single 4580 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 195/224 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 4580 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 4580/4535 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 4580 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 4580 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 4580?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 39.688 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 4580 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 4580?", "a": "The SKF 4580/4535 is a single-row tapered roller bearing with 50.8 mm bore, 104.775 mm outer diameter and 39.688 mm width (2 × 4.125 × 1.563 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 195 kN, C0 224 kN, fatigue load limit Pu 25 kN, reference speed 5,300 r/min, limiting speed 6,300 r/min, mass about 1650 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 4580 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 4500-series code marks the dimensional series. The metric dimensions 50.8×104.775×39.688 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "4580-4535", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "4580-4535" ], "locale_variants": {} }, { "sku": "537-532X", "brand": "SKF", "manufacturer_designation": "SKF 537/532 X", "series": "535-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 107.95, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 183, "static_load_kN": 190, "fatigue_load_limit_kN": 21.6, "max_rpm": 6300, "reference_speed_rpm": 5300, "limiting_speed_rpm": 6300, "weight_g": 1550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Dimensional interchange map: within the 53700 series at 50.8 mm bore, the 107.95 mm OD and 36.512 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 28.6 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 1550 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Cone versus cup responsibility in 537: the 537 cone carries the 50.8 mm bore, rollers and pressed-steel cage; the 532 X cup carries the 107.95 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.The SKF 537/532 X is a 50.8×107.95×36.512 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.In SKF inch-series tables 537 sits at 50.8 mm bore (2 in) with a 107.95 mm cup OD and 36.512 mm total width — dimensions that trace back to the original Timken boundary plan for the 535-series family. In SKF suffix language a bare 537 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 21.6 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.04 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Fit selection follows the rotating ring — interference on a rotating cone — and two 537 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "On this 50.8 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 537 pair heats, loses setting control and smears the roller-rib contact.", "The 535-series inch series at 50.8 mm bore (107.95×36.512 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 537 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Setting is a design value, not an assembly feel: excessive preload in the 537 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The 1550 g mass and 36.512 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 537.", "The 183/190 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 537 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 537/532 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 537?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 36.512 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 537 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 537?", "a": "The SKF 537/532 X is a single-row tapered roller bearing with 50.8 mm bore, 107.95 mm outer diameter and 36.512 mm width (2 × 4.25 × 1.437 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 183 kN, C0 190 kN, fatigue load limit Pu 21.6 kN, reference speed 5,300 r/min, limiting speed 6,300 r/min, mass about 1550 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 537 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 535-series code marks the dimensional series. The metric dimensions 50.8×107.95×36.512 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 537 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (535-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "537-532X-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 50.8×107.95×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "537-532X", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "537-532X" ], "locale_variants": {} }, { "sku": "LM806649-610", "brand": "SKF", "manufacturer_designation": "SKF LM 806649/610", "series": "LM806600-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 88.9, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 71.5, "static_load_kN": 78, "fatigue_load_limit_kN": 9, "max_rpm": 7000, "reference_speed_rpm": 6000, "limiting_speed_rpm": 7000, "weight_g": 440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Two catalogue entries share the LM 806649 cone but use different cups; this one, LM806649, takes the 610 cup and is ground for the resulting 88.9 mm OD / 19.05 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.SKF LM 806649/610 belongs to the SKF single-row tapered roller range — the 53.975 mm bore entry in the inch LM806600-series, dimensioned 88.9 mm OD and 19.05 mm wide.In SKF inch-series tables LM806649 sits at 53.975 mm bore (2.125 in) with a 88.9 mm cup OD and 19.05 mm total width — dimensions that trace back to the original Timken boundary plan for the LM806600-series family. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Selection arithmetic: the C0/C ratio is about 1.09 (static 78 kN against dynamic 71.5 kN), typical of a tapered roller sized for axial capacity, and the 9 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of LM806649 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Load system: the 71.5 kN basic dynamic rating C and 78 kN static rating C0 give a C0/C balance of 1.09, and dividing C by the 53.975 mm bore yields 1.32 kN per millimetre of journal — a density metric that compares across families; the 9 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 53.975 mm shaft carrying variable duty.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "On this 53.975 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight LM806649 pair heats, loses setting control and smears the roller-rib contact.", "The LM806600-series inch series at 53.975 mm bore (88.9×19.05 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the LM806649 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "At the 71.5 kN rating of LM806649, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 7,000 r/min speed end and heavier preload only where moment stiffness dominates.", "The LM806649 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 71.5/78 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM806649 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 806649/610 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is LM806649 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM806649?", "a": "The SKF LM 806649/610 is a single-row tapered roller bearing with 53.975 mm bore, 88.9 mm outer diameter and 19.05 mm width (2.125 × 3.5 × 0.75 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 71.5 kN, C0 78 kN, fatigue load limit Pu 9 kN, reference speed 6,000 r/min, limiting speed 7,000 r/min, mass about 440 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM806649 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM806600-series code marks the dimensional series. The metric dimensions 53.975×88.9×19.05 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM806649 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM806600-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM806649 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "LM806649-LM806610", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "LM806649-610", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM806649-610" ], "locale_variants": {} }, { "sku": "33895-33821", "brand": "SKF", "manufacturer_designation": "SKF 33895/33821", "series": "33800-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 95.25, "B_mm": 27.783, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 129, "static_load_kN": 137, "fatigue_load_limit_kN": 16, "max_rpm": 7000, "reference_speed_rpm": 5600, "limiting_speed_rpm": 7000, "weight_g": 810, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 33895 the 33895 cone contributes the 53.975 mm bore and roller set, the 33821 cup contributes the 95.25 mm OD raceway, and the assembled 27.783 mm width is the catalogue value.In SKF catalogue PUB BU/P1 17000, 33895 appears as SKF 33895/33821: an open, single-row tapered roller bearing in the 33800-series, supplied with a pressed-steel cage as standard.On the SKF nameplate, 33895 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 33800-series marking the dimensional series. In SKF suffix language a bare 33895 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. With C 129 kN and C0 137 kN, the 33895 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 7,000 r/min. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 33895 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Dimensional interchange map: within the 33800 series at 53.975 mm bore, the 95.25 mm OD and 27.783 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 20.6 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 810 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "differential and pinion drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "On this 53.975 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 33895 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 53.975 mm bore (95.25×27.783 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 33895 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 33895 mounting error.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 129/137 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 33895 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 33895/33821 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 33895 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 33895?", "a": "The SKF 33895/33821 is a single-row tapered roller bearing with 53.975 mm bore, 95.25 mm outer diameter and 27.783 mm width (2.125 × 3.75 × 1.094 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 129 kN, C0 137 kN, fatigue load limit Pu 16 kN, reference speed 5,600 r/min, limiting speed 7,000 r/min, mass about 810 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 33895 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 33800-series code marks the dimensional series. The metric dimensions 53.975×95.25×27.783 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 33895 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (33800-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 33895 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "33895-33822-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "33895-33821", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "33895-33821" ], "locale_variants": {} }, { "sku": "33895-33822", "brand": "SKF", "manufacturer_designation": "SKF 33895/33822", "series": "33800-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 95.25, "B_mm": 27.783, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 129, "static_load_kN": 137, "fatigue_load_limit_kN": 16, "max_rpm": 7000, "reference_speed_rpm": 5600, "limiting_speed_rpm": 7000, "weight_g": 810, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " For a 53.975 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 33895 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Load system: the 129 kN basic dynamic rating C and 137 kN static rating C0 give a C0/C balance of 1.06, and dividing C by the 53.975 mm bore yields 2.39 kN per millimetre of journal — a density metric that compares across families; the 16 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 53.975 mm shaft carrying variable duty. Why the cup reference matters here: in the 33800-series tables the 33895 cone appears against several cup options. 33895 is the pairing with 33822, and that choice — not the cone — fixes the 95.25 mm OD, the raceway track position and the 27.783 mm assembled width.33895 is a single-row tapered roller bearing in the 33800-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Reading the designation: 33895 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 33800-series code identifies the dimensional series. The 53.975 mm bore, 95.25 mm OD and 27.783 mm width are the metric equivalents of the inch boundary dimensions. In SKF suffix language a bare 33895 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 5,600 r/min reference speed the 20.6 mm-section 33895 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 7,000 r/min as the mechanical ceiling.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "On this 53.975 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 33895 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 53.975 mm bore (95.25×27.783 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "A single 33895 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "At the 129 kN rating of 33895, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 7,000 r/min speed end and heavier preload only where moment stiffness dominates.", "Open 33895 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 129/137 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 33895 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 33895/33822 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 33895 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 33895 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 33895?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 27.783 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 33895 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 33895?", "a": "The SKF 33895/33822 is a single-row tapered roller bearing with 53.975 mm bore, 95.25 mm outer diameter and 27.783 mm width (2.125 × 3.75 × 1.094 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 129 kN, C0 137 kN, fatigue load limit Pu 16 kN, reference speed 5,600 r/min, limiting speed 7,000 r/min, mass about 810 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 33895 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 33800-series code marks the dimensional series. The metric dimensions 53.975×95.25×27.783 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "33895-33822-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "33895-33822", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "33895-33822" ], "locale_variants": {} }, { "sku": "539-532X", "brand": "SKF", "manufacturer_designation": "SKF 539/532 X", "series": "535-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 107.95, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 183, "static_load_kN": 190, "fatigue_load_limit_kN": 21.6, "max_rpm": 6300, "reference_speed_rpm": 5300, "limiting_speed_rpm": 6300, "weight_g": 1450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The 21.6 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.04 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. For a 53.975 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 539 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Dimensional interchange map: within the 53900 series at 53.975 mm bore, the 107.95 mm OD and 36.512 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 27.0 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 1450 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Housing and abutment design flows from the cup: in 539 the 532 X cup fixes the 107.95 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the 539 cone determines the 53.975 mm shaft interface; the 36.512 mm width is the assembled pair value.The SKF 539/532 X is a 53.975×107.95×36.512 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.The 535-series series assigns 53.975 mm bore, 107.95 mm OD and 36.512 mm width to 539; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "On this 53.975 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 539 pair heats, loses setting control and smears the roller-rib contact.", "The 535-series inch series at 53.975 mm bore (107.95×36.512 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 539 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 539 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The 539 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 183/190 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 539 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 539/532 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 539 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 539 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 539 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 539?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 36.512 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 539 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 539?", "a": "The SKF 539/532 X is a single-row tapered roller bearing with 53.975 mm bore, 107.95 mm outer diameter and 36.512 mm width (2.125 × 4.25 × 1.437 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 183 kN, C0 190 kN, fatigue load limit Pu 21.6 kN, reference speed 5,300 r/min, limiting speed 6,300 r/min, mass about 1450 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "539-532X-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 53.975×107.95×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "539-532X", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "539-532X" ], "locale_variants": {} }, { "sku": "539-532A", "brand": "SKF", "manufacturer_designation": "SKF 539/532 A", "series": "535-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 111.125, "B_mm": 38.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 183, "static_load_kN": 190, "fatigue_load_limit_kN": 21.6, "max_rpm": 6300, "reference_speed_rpm": 5300, "limiting_speed_rpm": 6300, "weight_g": 1650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The 21.6 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.04 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. For a 53.975 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 539 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Dimensional interchange map: within the 53900 series at 53.975 mm bore, the 111.125 mm OD and 38.1 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 28.6 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 1650 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Cup-side note for 532 A: the outer ring's rib profile and the 111.125 mm outside diameter are cup-specific within the 535-series tables, so substituting a different cup against the same 539 cone changes both the assembled 38.1 mm width and the axial free-play setting of the mounted pair.The SKF 539/532 A is a 53.975×111.125×38.1 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.The 535-series series assigns 53.975 mm bore, 111.125 mm OD and 38.1 mm width to 539; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "On this 53.975 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 539 pair heats, loses setting control and smears the roller-rib contact.", "The 535-series inch series at 53.975 mm bore (111.125×38.1 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 539 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 539 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The 539 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 183/190 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 539 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 539/532 A designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 539 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 539 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 539 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 539?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 38.1 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 539 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 539?", "a": "The SKF 539/532 A is a single-row tapered roller bearing with 53.975 mm bore, 111.125 mm outer diameter and 38.1 mm width (2.125 × 4.375 × 1.5 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 183 kN, C0 190 kN, fatigue load limit Pu 21.6 kN, reference speed 5,300 r/min, limiting speed 6,300 r/min, mass about 1650 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "539-532X-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "539-532A", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "539-532A" ], "locale_variants": {} }, { "sku": "72212-72487", "brand": "SKF", "manufacturer_designation": "SKF 72212/72487", "series": "72000-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 123.825, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 174, "static_load_kN": 160, "fatigue_load_limit_kN": 19.6, "max_rpm": 5600, "reference_speed_rpm": 4300, "limiting_speed_rpm": 5600, "weight_g": 2000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 72212 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Operating context for the 53.975 mm bore: a shaft of this diameter in the medium-bore band typically runs between 43180 and 64770 r/min in real machinery, and the 123.825 mm outside diameter places the housing shoulder at 132 mm outer abutment; the 36.512 mm width and 2000 g mass together set the shaft critical speed and the housing resonance check for this 72200-series envelope. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 72212 the 72212 cone contributes the 53.975 mm bore and roller set, the 72487 cup contributes the 123.825 mm OD raceway, and the assembled 36.512 mm width is the catalogue value.SKF 72212 (SKF 72212/72487) is the 72000-series tapered roller choice for a 53.975 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 123.825×36.512 mm envelope.In SKF inch-series tables 72212 sits at 53.975 mm bore (2.125 in) with a 123.825 mm cup OD and 36.512 mm total width — dimensions that trace back to the original Timken boundary plan for the 72000-series family. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 2000 g for the 53.975×123.825×36.512 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "On this 53.975 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 72212 pair heats, loses setting control and smears the roller-rib contact.", "The 72000-series inch series at 53.975 mm bore (123.825×36.512 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 72212 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 72212 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Catalogue reference speed and limiting speed are different limits: the 4,300 r/min reference is a thermal criterion under load, while the 5,600 r/min limiting value is the mechanical ceiling — observe both.", "The 174/160 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 72212 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 72212/72487 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 72212 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 72212 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 72212?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 36.512 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 72212 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 72212?", "a": "The SKF 72212/72487 is a single-row tapered roller bearing with 53.975 mm bore, 123.825 mm outer diameter and 36.512 mm width (2.125 × 4.875 × 1.437 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 174 kN, C0 160 kN, fatigue load limit Pu 19.6 kN, reference speed 4,300 r/min, limiting speed 5,600 r/min, mass about 2000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 72212 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 72000-series code marks the dimensional series. The metric dimensions 53.975×123.825×36.512 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "72212-72487", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "72212-72487" ], "locale_variants": {} }, { "sku": "387-382A", "brand": "SKF", "manufacturer_designation": "SKF 387/382 A", "series": "385-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 96.838, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 99.9, "static_load_kN": 102, "fatigue_load_limit_kN": 11.6, "max_rpm": 6700, "reference_speed_rpm": 5600, "limiting_speed_rpm": 6700, "weight_g": 590, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The 21.4 mm radial section height ((96.838−53.975)/2) and 590 g catalogue mass frame a 53.975 mm bore bearing rated at 99.9 kN C — roughly 1.85 kN of dynamic capacity per millimetre of bore before application factors. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 387 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Speed envelope and thermal behaviour: at 5,600 r/min thermal reference, the 53.975 mm bore shaft runs at a dn of 302k, and the 21.4 mm section dissipates heat through the cup-to-housing contact path; the 6,700 r/min mechanical ceiling reflects cage strength, and the 590 g spinning cone contributes gyroscopic moment under rapid speed reversal. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 387 the 387 cone contributes the 53.975 mm bore and roller set, the 382 A cup contributes the 96.838 mm OD raceway, and the assembled 21 mm width is the catalogue value.The SKF 387/382 A is a 53.975×96.838×21 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.The 385-series series assigns 53.975 mm bore, 96.838 mm OD and 21 mm width to 387; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "belt-driven fan and blower shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "On this 53.975 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 387 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 53.975 mm bore (96.838×21 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 387 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 387 mounting error.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 96.838 mm cup race release as noise within the first running hours.", "The 99.9/102 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 387 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 387/382 A designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 387 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 387 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 387 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 387?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 21 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 387 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 387?", "a": "The SKF 387/382 A is a single-row tapered roller bearing with 53.975 mm bore, 96.838 mm outer diameter and 21 mm width (2.125 × 3.813 × 0.827 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 99.9 kN, C0 102 kN, fatigue load limit Pu 11.6 kN, reference speed 5,600 r/min, limiting speed 6,700 r/min, mass about 590 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "387-382A-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "387-382A", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "387-382A" ], "locale_variants": {} }, { "sku": "387A-382S", "brand": "SKF", "manufacturer_designation": "SKF 387 A/382 S", "series": "385-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 96.838, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 99.9, "static_load_kN": 102, "fatigue_load_limit_kN": 11.6, "max_rpm": 6700, "reference_speed_rpm": 5600, "limiting_speed_rpm": 6700, "weight_g": 650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Cone-and-cup identity in 387A: the leading 387 A reference identifies the inner ring, rollers and cage; the trailing 382 S reference identifies the outer ring. The 385-series series lists alternative cups for the same cone, each producing a different 96.838 mm OD or 25.4 mm width — hence a different SKU even though the bore stays at 53.975 mm.387A is a single-row tapered roller bearing in the 385-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Digit by digit, 387A reads as cone reference / cup reference in the 385-series inch series; the 53.975 mm bore, 96.838 mm OD and 25.4 mm width are the metric equivalents of the original inch boundary values. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Selection arithmetic: the C0/C ratio is about 1.02 (static 102 kN against dynamic 99.9 kN), typical of a tapered roller sized for axial capacity, and the 11.6 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Fit selection follows the rotating ring — interference on a rotating cone — and two 387A units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Cross-section geometry: the 21.4 mm half-section ((96.838−53.975)/2) of this 38700-series unit places the roller large-end pitch diameter at roughly 75 mm, and the 25.4 mm axial width is split between cone (14 mm) and cup rib (11 mm) — a geometry that sets the contact angle and, with the 650 g rotating cone mass, the critical speed at which cage-roller imbalance begins.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "axle-boxes in material-handling equipment" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "On this 53.975 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 387A pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 53.975 mm bore (96.838×25.4 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 387A pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 387A pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The 387A shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 99.9/102 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 387A (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 387 A/382 S designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 387A interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 387A?", "a": "The SKF 387 A/382 S is a single-row tapered roller bearing with 53.975 mm bore, 96.838 mm outer diameter and 25.4 mm width (2.125 × 3.813 × 1 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 99.9 kN, C0 102 kN, fatigue load limit Pu 11.6 kN, reference speed 5,600 r/min, limiting speed 6,700 r/min, mass about 650 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 387A inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 385-series code marks the dimensional series. The metric dimensions 53.975×96.838×25.4 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 387A mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (385-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 387A take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "387A-382A", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "387A-382S", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "387A-382S" ], "locale_variants": {} }, { "sku": "387-382", "brand": "SKF", "manufacturer_designation": "SKF 387/382", "series": "385-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 98.425, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 99.9, "static_load_kN": 102, "fatigue_load_limit_kN": 11.6, "max_rpm": 6700, "reference_speed_rpm": 5600, "limiting_speed_rpm": 6700, "weight_g": 640, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " From a specification standpoint the 382 cup is the controlling half of 387 for housing design — it sets the 98.425 mm OD and the outer abutment diameter — while the 387 cone controls shaft fit at the 53.975 mm bore; the 21 mm width is the result of the two together.For a 53.975 mm shaft carrying combined load, SKF lists 387 under catalogue execution SKF 387/382: one open single-row tapered roller bearing in the inch 385-series.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (385-series) ties the pair to a specific boundary plan. Dimensions 53.975×98.425×21 mm are the converted metric envelope. In SKF suffix language a bare 387 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Speed planning uses two different ceilings: 5,600 r/min thermal reference and 6,700 r/min mechanical limiting speed. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 387 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Dimensional interchange map: within the 38700 series at 53.975 mm bore, the 98.425 mm OD and 21 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 22.2 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 640 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "On this 53.975 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 387 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 53.975 mm bore (98.425×21 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "Do not mix brands or executions inside one 387 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 387 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Shaft and housing fillets must clear the bearing chamfer so the 21 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 99.9/102 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 387 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 387/382 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 387 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 387?", "a": "The SKF 387/382 is a single-row tapered roller bearing with 53.975 mm bore, 98.425 mm outer diameter and 21 mm width (2.125 × 3.875 × 0.827 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 99.9 kN, C0 102 kN, fatigue load limit Pu 11.6 kN, reference speed 5,600 r/min, limiting speed 6,700 r/min, mass about 640 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 387 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 385-series code marks the dimensional series. The metric dimensions 53.975×98.425×21 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 387 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (385-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 387 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "387-382A-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "387-382", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "387-382" ], "locale_variants": {} }, { "sku": "462-453X", "brand": "SKF", "manufacturer_designation": "SKF 462/453 X", "series": "455-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 104.775, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 150, "static_load_kN": 160, "fatigue_load_limit_kN": 18.6, "max_rpm": 6300, "reference_speed_rpm": 5300, "limiting_speed_rpm": 6300, "weight_g": 1050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Mounting practice for 462: the rotating cone takes the interference fit (k5 on a 53.975 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Journal and housing interface: the 53.975 mm bore takes a k5 shaft seat (upper deviation ~0.108 mm for this diameter range) and the 104.775 mm outside diameter pairs with an H7 housing bore tolerance band of 104.775.000/104.795 mm; the 30.162 mm width defines the shoulder depth, and the 1050 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Cone-and-cup identity in 462: the leading 462 reference identifies the inner ring, rollers and cage; the trailing 453 X reference identifies the outer ring. The 455-series series lists alternative cups for the same cone, each producing a different 104.775 mm OD or 30.162 mm width — hence a different SKU even though the bore stays at 53.975 mm.462 is a single-row tapered roller bearing in the 455-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Reading the designation: 462 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 455-series code identifies the dimensional series. The 53.975 mm bore, 104.775 mm OD and 30.162 mm width are the metric equivalents of the inch boundary dimensions. In SKF suffix language a bare 462 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Catalogue mass 1050 g for the 53.975×104.775×30.162 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "industrial gearbox shafts and reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 53.975 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 462 pair heats, loses setting control and smears the roller-rib contact.", "The 455-series inch series at 53.975 mm bore (104.775×30.162 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 462 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 462 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The 462 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 150/160 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 462 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 462/453 X designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 462 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 462 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 462?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 30.162 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 462 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 462?", "a": "The SKF 462/453 X is a single-row tapered roller bearing with 53.975 mm bore, 104.775 mm outer diameter and 30.162 mm width (2.125 × 4.125 × 1.187 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 150 kN, C0 160 kN, fatigue load limit Pu 18.6 kN, reference speed 5,300 r/min, limiting speed 6,300 r/min, mass about 1050 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 462 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 455-series code marks the dimensional series. The metric dimensions 53.975×104.775×30.162 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "462-453X-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "462-453X", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "462-453X" ], "locale_variants": {} }, { "sku": "39580-39520", "brand": "SKF", "manufacturer_designation": "SKF 39580/39520", "series": "39500-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 175, "static_load_kN": 204, "fatigue_load_limit_kN": 23.6, "max_rpm": 5600, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5600, "weight_g": 1400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Numbering ties the bearing to its inch-series envelope: 39580 means a cone and cup matched pair in the 39500-series series — which is why the 53.975×112.712×30.162 mm outline swaps dimensionally with other inch-series bearings of the same code. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 1400 g for the 53.975×112.712×30.162 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 39580 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Operating context for the 53.975 mm bore: a shaft of this diameter in the medium-bore band typically runs between 43180 and 64770 r/min in real machinery, and the 112.712 mm outside diameter places the housing shoulder at 121 mm outer abutment; the 30.162 mm width and 1400 g mass together set the shaft critical speed and the housing resonance check for this 39500-series envelope. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 39580 the 39580 cone contributes the 53.975 mm bore and roller set, the 39520 cup contributes the 112.712 mm OD raceway, and the assembled 30.162 mm width is the catalogue value.Ordering number SKF 39580/39520 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 53.975 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "belt-driven fan and blower shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "On this 53.975 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 39580 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 53.975 mm bore (112.712×30.162 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "At the 175 kN rating of 39580, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 5,600 r/min speed end and heavier preload only where moment stiffness dominates.", "Do not mix brands or executions inside one 39580 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 112.712 mm cup race release as noise within the first running hours.", "The 175/204 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 39580 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 39580/39520 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 39580 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 39500-series code marks the dimensional series. The metric dimensions 53.975×112.712×30.162 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 39580 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (39500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 39580 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 39580 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 39580 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 39580?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 30.162 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "39580-39520-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "39580-39520", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "39580-39520" ], "locale_variants": {} }, { "sku": "39581-39520", "brand": "SKF", "manufacturer_designation": "SKF 39581/39520", "series": "39500-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 175, "static_load_kN": 204, "fatigue_load_limit_kN": 23.6, "max_rpm": 5600, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5600, "weight_g": 1400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Reading the designation: 39581 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 39500-series code identifies the dimensional series. The 53.975 mm bore, 112.712 mm OD and 30.162 mm width are the metric equivalents of the inch boundary dimensions. In SKF suffix language a bare 39581 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 4,500 r/min reference speed the 29.4 mm-section 39581 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 5,600 r/min as the mechanical ceiling. Because the contact line is tapered, one 39581 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 53.975 mm shaft typically takes a k5 seat with an H7 housing bore. Speed envelope and thermal behaviour: at 4,500 r/min thermal reference, the 53.975 mm bore shaft runs at a dn of 243k, and the 29.4 mm section dissipates heat through the cup-to-housing contact path; the 5,600 r/min mechanical ceiling reflects cage strength, and the 1400 g spinning cone contributes gyroscopic moment under rapid speed reversal. From a specification standpoint the 39520 cup is the controlling half of 39581 for housing design — it sets the 112.712 mm OD and the outer abutment diameter — while the 39581 cone controls shaft fit at the 53.975 mm bore; the 30.162 mm width is the result of the two together.39581 is a single-row tapered roller bearing in the 39500-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "On this 53.975 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 39581 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 53.975 mm bore (112.712×30.162 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 39581 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 39581 mounting error.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 175/204 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 39581 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 39581/39520 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 39581 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 39500-series code marks the dimensional series. The metric dimensions 53.975×112.712×30.162 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 39581 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (39500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 39581 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 39581 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 39581 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 39581?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 30.162 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "39581-39520-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "39581-39520", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "39581-39520" ], "locale_variants": {} }, { "sku": "39580-39528", "brand": "SKF", "manufacturer_designation": "SKF 39580/39528", "series": "39500-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 119.985, "B_mm": 32.751, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 175, "static_load_kN": 204, "fatigue_load_limit_kN": 23.6, "max_rpm": 5600, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5600, "weight_g": 1750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Numbering ties the bearing to its inch-series envelope: 39580 means a cone and cup matched pair in the 39500-series series — which is why the 53.975×119.985×32.751 mm outline swaps dimensionally with other inch-series bearings of the same code. In SKF suffix language a bare 39580 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Catalogue mass 1750 g for the 53.975×119.985×32.751 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 39580 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Operating context for the 53.975 mm bore: a shaft of this diameter in the medium-bore band typically runs between 43180 and 64770 r/min in real machinery, and the 119.985 mm outside diameter places the housing shoulder at 128 mm outer abutment; the 32.751 mm width and 1750 g mass together set the shaft critical speed and the housing resonance check for this 39500-series envelope. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 39580 the 39580 cone contributes the 53.975 mm bore and roller set, the 39528 cup contributes the 119.985 mm OD raceway, and the assembled 32.751 mm width is the catalogue value.Ordering number SKF 39580/39528 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 53.975 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "belt-driven fan and blower shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "On this 53.975 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 39580 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 53.975 mm bore (119.985×32.751 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "At the 175 kN rating of 39580, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 5,600 r/min speed end and heavier preload only where moment stiffness dominates.", "Do not mix brands or executions inside one 39580 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 119.985 mm cup race release as noise within the first running hours.", "The 175/204 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 39580 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 39580/39528 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 39580 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 39500-series code marks the dimensional series. The metric dimensions 53.975×119.985×32.751 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 39580 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (39500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 39580 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 39580 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 39580 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 39580?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 32.751 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "39580-39520-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "39580-39528", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "39580-39528" ], "locale_variants": {} }, { "sku": "39581-39528", "brand": "SKF", "manufacturer_designation": "SKF 39581/39528", "series": "39500-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 119.985, "B_mm": 32.751, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 175, "static_load_kN": 204, "fatigue_load_limit_kN": 23.6, "max_rpm": 5600, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5600, "weight_g": 1750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Reading the designation: 39581 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 39500-series code identifies the dimensional series. The 53.975 mm bore, 119.985 mm OD and 32.751 mm width are the metric equivalents of the inch boundary dimensions. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. At 4,500 r/min reference speed the 33.0 mm-section 39581 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 5,600 r/min as the mechanical ceiling. Because the contact line is tapered, one 39581 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 53.975 mm shaft typically takes a k5 seat with an H7 housing bore. Speed envelope and thermal behaviour: at 4,500 r/min thermal reference, the 53.975 mm bore shaft runs at a dn of 243k, and the 33.0 mm section dissipates heat through the cup-to-housing contact path; the 5,600 r/min mechanical ceiling reflects cage strength, and the 1750 g spinning cone contributes gyroscopic moment under rapid speed reversal. From a specification standpoint the 39528 cup is the controlling half of 39581 for housing design — it sets the 119.985 mm OD and the outer abutment diameter — while the 39581 cone controls shaft fit at the 53.975 mm bore; the 32.751 mm width is the result of the two together.39581 is a single-row tapered roller bearing in the 39500-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "automotive and light-truck wheel hubs" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "On this 53.975 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 39581 pair heats, loses setting control and smears the roller-rib contact.", "The 320 series at 53.975 mm bore (119.985×32.751 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 39581 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 39581 mounting error.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 175/204 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 39581 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 39581/39528 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 39581 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 39500-series code marks the dimensional series. The metric dimensions 53.975×119.985×32.751 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 39581 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (39500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 39581 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 39581 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 39581 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 39581?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 32.751 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "39581-39520-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "39581-39528", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "39581-39528" ], "locale_variants": {} }, { "sku": "HM911244-210", "brand": "SKF", "manufacturer_designation": "SKF HM 911244/210", "series": "HM911200-series", "type": "tapered_roller", "d_mm": 59.987, "D_mm": 130.175, "B_mm": 34.099, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 187, "static_load_kN": 180, "fatigue_load_limit_kN": 22, "max_rpm": 5000, "reference_speed_rpm": 3800, "limiting_speed_rpm": 5000, "weight_g": 2050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Cup-side note for 210: the outer ring's rib profile and the 130.175 mm outside diameter are cup-specific within the HM911200-series tables, so substituting a different cup against the same HM 911244 cone changes both the assembled 34.099 mm width and the axial free-play setting of the mounted pair.HM911244 is a single-row tapered roller bearing in the HM911200-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Numbering ties the bearing to its inch-series envelope: HM911244 means a cone and cup matched pair in the HM911200-series series — which is why the 59.987×130.175×34.099 mm outline swaps dimensionally with other inch-series bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 22 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 0.96 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of HM911244 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Material and manufacturing detail: the 2050 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the HM900 ISO envelope, with the pressed-steel cage contributing roughly 62 g of the total; the 59.987 mm bore is ground to IT5 roundness and the 130.175 mm OD to IT5 cylindricity, and the 34.099 mm width tolerance keeps the pair-setting scatter within the ISO preload class.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "paper-machine and printing rolls" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "Mount the 59.987 mm bore HM911244 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The HM911200-series inch series at 59.987 mm bore (130.175×34.099 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single HM911244 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Do not mix brands or executions inside one HM911244 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Catalogue reference speed and limiting speed are different limits: the 3,800 r/min reference is a thermal criterion under load, while the 5,000 r/min limiting value is the mechanical ceiling — observe both.", "The 187/180 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM911244 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 911244/210 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is HM911244 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM911244?", "a": "The SKF HM 911244/210 is a single-row tapered roller bearing with 59.987 mm bore, 130.175 mm outer diameter and 34.099 mm width (2.362 × 5.125 × 1.342 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 187 kN, C0 180 kN, fatigue load limit Pu 22 kN, reference speed 3,800 r/min, limiting speed 5,000 r/min, mass about 2050 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM911244 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM911200-series code marks the dimensional series. The metric dimensions 59.987×130.175×34.099 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM911244 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM911200-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single HM911244 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "HM911244-210", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM911244-210" ], "locale_variants": {} }, { "sku": "6391-K-6320", "brand": "SKF", "manufacturer_designation": "SKF 6391/K-6320", "series": "6300-series", "type": "tapered_roller", "d_mm": 59.987, "D_mm": 135.755, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 353, "static_load_kN": 400, "fatigue_load_limit_kN": 45.5, "max_rpm": 5000, "reference_speed_rpm": 4000, "limiting_speed_rpm": 5000, "weight_g": 3950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "On the SKF nameplate, 6391 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 6300-series marking the dimensional series. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 37.9 mm radial section height ((135.755−59.987)/2) and 3950 g catalogue mass frame a 59.987 mm bore bearing rated at 353 kN C — roughly 5.88 kN of dynamic capacity per millimetre of bore before application factors. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 6391 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Operating context for the 59.987 mm bore: a shaft of this diameter in the large-bore band typically runs between 47990 and 71984 r/min in real machinery, and the 135.755 mm outside diameter places the housing shoulder at 144 mm outer abutment; the 53.975 mm width and 3950 g mass together set the shaft critical speed and the housing resonance check for this 63900-series envelope. Housing and abutment design flows from the cup: in 6391 the K-6320 cup fixes the 135.755 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the 6391 cone determines the 59.987 mm shaft interface; the 53.975 mm width is the assembled pair value.In SKF catalogue PUB BU/P1 17000, 6391 appears as SKF 6391/K-6320: an open, single-row tapered roller bearing in the 6300-series, supplied with a pressed-steel cage as standard.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "crane sheave and hoist gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Mount the 59.987 mm bore 6391 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 6300-series inch series at 59.987 mm bore (135.755×53.975 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 6391 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 6391 mounting error.", "Catalogue reference speed and limiting speed are different limits: the 4,000 r/min reference is a thermal criterion under load, while the 5,000 r/min limiting value is the mechanical ceiling — observe both.", "The 353/400 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 6391 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 6391/K-6320 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 6391 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 6300-series code marks the dimensional series. The metric dimensions 59.987×135.755×53.975 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 6391 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (6300-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 6391 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 6391 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 6391 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 6391?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 53.975 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "6391-K-6320", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "6391-K-6320" ], "locale_variants": {} }, { "sku": "HM911245-210", "brand": "SKF", "manufacturer_designation": "SKF HM 911245/210", "series": "HM911200-series", "type": "tapered_roller", "d_mm": 60.325, "D_mm": 130.175, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 187, "static_load_kN": 180, "fatigue_load_limit_kN": 22.4, "max_rpm": 5000, "reference_speed_rpm": 3800, "limiting_speed_rpm": 5000, "weight_g": 2100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "On the SKF nameplate, HM911245 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the HM911200-series marking the dimensional series. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 2100 g for the 60.325×130.175×36.512 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Fit selection follows the rotating ring — interference on a rotating cone — and two HM911245 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Speed envelope and thermal behaviour: at 3,800 r/min thermal reference, the 60.325 mm bore shaft runs at a dn of 229k, and the 34.9 mm section dissipates heat through the cup-to-housing contact path; the 5,000 r/min mechanical ceiling reflects cage strength, and the 2100 g spinning cone contributes gyroscopic moment under rapid speed reversal. Why the cup reference matters here: in the HM911200-series tables the HM 911245 cone appears against several cup options. HM911245 is the pairing with 210, and that choice — not the cone — fixes the 130.175 mm OD, the raceway track position and the 36.512 mm assembled width.SKF HM 911245/210 belongs to the SKF single-row tapered roller range — the 60.325 mm bore entry in the inch HM911200-series, dimensioned 130.175 mm OD and 36.512 mm wide.", "applications": [ "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives", "construction machinery drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "Mount the 60.325 mm bore HM911245 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The HM911200-series inch series at 60.325 mm bore (130.175×36.512 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the HM911245 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "A single HM911245 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Shaft and housing fillets must clear the bearing chamfer so the 36.512 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 187/180 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM911245 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 911245/210 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the HM911245 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM911200-series code marks the dimensional series. The metric dimensions 60.325×130.175×36.512 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM911245 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM911200-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single HM911245 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HM911245 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM911245 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HM911245?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 36.512 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "HM911245-HM911210", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "HM911245-210", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM911245-210" ], "locale_variants": {} }, { "sku": "395-394A", "brand": "SKF", "manufacturer_designation": "SKF 395/394 A", "series": "395-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 110, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 108, "static_load_kN": 118, "fatigue_load_limit_kN": 13.4, "max_rpm": 6000, "reference_speed_rpm": 4800, "limiting_speed_rpm": 6000, "weight_g": 840, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 840 g for the 63.5×110×22 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. For a 63.5 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 395 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Speed envelope and thermal behaviour: at 4,800 r/min thermal reference, the 63.5 mm bore shaft runs at a dn of 305k, and the 23.3 mm section dissipates heat through the cup-to-housing contact path; the 6,000 r/min mechanical ceiling reflects cage strength, and the 840 g spinning cone contributes gyroscopic moment under rapid speed reversal. Inch tapered bearings are matched sets, not mix-and-match components: 395 pairs the 395 cone with the 394 A cup under the 395-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.The SKF 395/394 A is a 63.5×110×22 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.Digit by digit, 395 reads as cone reference / cup reference in the 395-series inch series; the 63.5 mm bore, 110 mm OD and 22 mm width are the metric equivalents of the original inch boundary values.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "marine deck machinery shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "Mount the 63.5 mm bore 395 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 63.5 mm bore (110×22 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "A single 395 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 395 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Shaft and housing fillets must clear the bearing chamfer so the 22 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 108/118 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 395 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 395/394 A designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in 395 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (395-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 395 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 395 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 395 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 395?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 22 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 395 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "395-394A", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "395-394A" ], "locale_variants": {} }, { "sku": "39585-39520", "brand": "SKF", "manufacturer_designation": "SKF 39585/39520", "series": "39500-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 175, "static_load_kN": 204, "fatigue_load_limit_kN": 23.6, "max_rpm": 5600, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5600, "weight_g": 1250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Two catalogue entries share the 39585 cone but use different cups; this one, 39585, takes the 39520 cup and is ground for the resulting 112.712 mm OD / 30.162 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.In SKF catalogue PUB BU/P1 17000, 39585 appears as SKF 39585/39520: an open, single-row tapered roller bearing in the 39500-series, supplied with a pressed-steel cage as standard.Reading the designation: 39585 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 39500-series code identifies the dimensional series. The 63.5 mm bore, 112.712 mm OD and 30.162 mm width are the metric equivalents of the inch boundary dimensions. In SKF suffix language a bare 39585 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. With C 175 kN and C0 204 kN, the 39585 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 5,600 r/min. Because the contact line is tapered, one 39585 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 63.5 mm shaft typically takes a k5 seat with an H7 housing bore. Journal and housing interface: the 63.5 mm bore takes a k5 shaft seat (upper deviation ~0.127 mm for this diameter range) and the 112.712 mm outside diameter pairs with an H7 housing bore tolerance band of 112.712.000/112.732 mm; the 30.162 mm width defines the shoulder depth, and the 1250 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "rolling-mill auxiliary drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "Mount the 63.5 mm bore 39585 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 63.5 mm bore (112.712×30.162 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "At the 175 kN rating of 39585, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 5,600 r/min speed end and heavier preload only where moment stiffness dominates.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 39585 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 112.712 mm cup race release as noise within the first running hours.", "The 175/204 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 39585 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 39585/39520 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 39585 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 39585?", "a": "The SKF 39585/39520 is a single-row tapered roller bearing with 63.5 mm bore, 112.712 mm outer diameter and 30.162 mm width (2.5 × 4.437 × 1.187 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 175 kN, C0 204 kN, fatigue load limit Pu 23.6 kN, reference speed 4,500 r/min, limiting speed 5,600 r/min, mass about 1250 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 39585 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 39500-series code marks the dimensional series. The metric dimensions 63.5×112.712×30.162 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 39585 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (39500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 39585 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "39585-39520-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 63.5×112.712×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "39585-39520", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "39585-39520" ], "locale_variants": {} }, { "sku": "3982-3920", "brand": "SKF", "manufacturer_designation": "SKF 3982/3920", "series": "3980-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 112.712, "B_mm": 30.163, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 152, "static_load_kN": 183, "fatigue_load_limit_kN": 21.2, "max_rpm": 5600, "reference_speed_rpm": 4800, "limiting_speed_rpm": 5600, "weight_g": 1250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 3982 (SKF 3982/3920) is the 3980-series tapered roller choice for a 63.5 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 112.712×30.163 mm envelope.Digit by digit, 3982 reads as cone reference / cup reference in the 3980-series inch series; the 63.5 mm bore, 112.712 mm OD and 30.163 mm width are the metric equivalents of the original inch boundary values. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. At 4,800 r/min reference speed the 24.6 mm-section 3982 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 5,600 r/min as the mechanical ceiling. Because the contact line is tapered, one 3982 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 63.5 mm shaft typically takes a k5 seat with an H7 housing bore. Dimensional interchange map: within the 39800 series at 63.5 mm bore, the 112.712 mm OD and 30.163 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 24.6 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 1250 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 3982 the 3982 cone contributes the 63.5 mm bore and roller set, the 3920 cup contributes the 112.712 mm OD raceway, and the assembled 30.163 mm width is the catalogue value.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "marine deck machinery shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Mount the 63.5 mm bore 3982 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 63.5 mm bore (112.712×30.163 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 3982 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Do not mix brands or executions inside one 3982 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Open 3982 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 152/183 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 3982 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 3982/3920 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 3982?", "a": "The SKF 3982/3920 is a single-row tapered roller bearing with 63.5 mm bore, 112.712 mm outer diameter and 30.163 mm width (2.5 × 4.437 × 1.188 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 152 kN, C0 183 kN, fatigue load limit Pu 21.2 kN, reference speed 4,800 r/min, limiting speed 5,600 r/min, mass about 1250 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 3982 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 3980-series code marks the dimensional series. The metric dimensions 63.5×112.712×30.163 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 3982 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (3980-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 3982 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 3982 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 3982 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "3982-3920-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 63.5×112.712×30.163 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "3982-3920", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "3982-3920" ], "locale_variants": {} }, { "sku": "6379-K-6320", "brand": "SKF", "manufacturer_designation": "SKF 6379/K-6320", "series": "6300-series", "type": "tapered_roller", "d_mm": 65.088, "D_mm": 135.755, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 353, "static_load_kN": 400, "fatigue_load_limit_kN": 45.5, "max_rpm": 5000, "reference_speed_rpm": 4000, "limiting_speed_rpm": 5000, "weight_g": 3700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Load system: the 353 kN basic dynamic rating C and 400 kN static rating C0 give a C0/C balance of 1.13, and dividing C by the 65.088 mm bore yields 5.42 kN per millimetre of journal — a density metric that compares across families; the 45.5 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 65.088 mm shaft carrying variable duty. Cone-and-cup identity in 6379: the leading 6379 reference identifies the inner ring, rollers and cage; the trailing K-6320 reference identifies the outer ring. The 6300-series series lists alternative cups for the same cone, each producing a different 135.755 mm OD or 53.975 mm width — hence a different SKU even though the bore stays at 65.088 mm.The SKF 6379/K-6320 is a 65.088×135.755×53.975 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (6300-series) ties the pair to a specific boundary plan. Dimensions 65.088×135.755×53.975 mm are the converted metric envelope. In SKF suffix language a bare 6379 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. With C 353 kN and C0 400 kN, the 6379 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 5,000 r/min. Mounting practice for 6379: the rotating cone takes the interference fit (k5 on a 65.088 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing.", "applications": [ "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Mount the 65.088 mm bore 6379 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 6300-series inch series at 65.088 mm bore (135.755×53.975 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 6379 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 6379 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The 6379 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 353/400 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 6379 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 6379/K-6320 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 6379?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 53.975 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 6379 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 6379?", "a": "The SKF 6379/K-6320 is a single-row tapered roller bearing with 65.088 mm bore, 135.755 mm outer diameter and 53.975 mm width (2.563 × 5.345 × 2.125 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 353 kN, C0 400 kN, fatigue load limit Pu 45.5 kN, reference speed 4,000 r/min, limiting speed 5,000 r/min, mass about 3700 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 6379 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 6300-series code marks the dimensional series. The metric dimensions 65.088×135.755×53.975 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 6379 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (6300-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "6379-6320", "equiv_brand": "NTN", "level": "partial", "note": "Same 65.088×135.755×53.975 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "6379-K-6320", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "6379-K-6320" ], "locale_variants": {} }, { "sku": "395A-394A", "brand": "SKF", "manufacturer_designation": "SKF 395 A/394 A", "series": "395-series", "type": "tapered_roller", "d_mm": 65.088, "D_mm": 110, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 108, "static_load_kN": 118, "fatigue_load_limit_kN": 13.4, "max_rpm": 6000, "reference_speed_rpm": 4800, "limiting_speed_rpm": 6000, "weight_g": 790, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF inch-series tables 395A sits at 65.088 mm bore (2.563 in) with a 110 mm cup OD and 22 mm total width — dimensions that trace back to the original Timken boundary plan for the 395-series family. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Selection arithmetic: the C0/C ratio is about 1.09 (static 118 kN against dynamic 108 kN), typical of a tapered roller sized for axial capacity, and the 13.4 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 395A generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Dimensional interchange map: within the 39500 series at 65.088 mm bore, the 110 mm OD and 22 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 22.5 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 790 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Two catalogue entries share the 395 A cone but use different cups; this one, 395A, takes the 394 A cup and is ground for the resulting 110 mm OD / 22 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.SKF 395A (SKF 395 A/394 A) is the 395-series tapered roller choice for a 65.088 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 110×22 mm envelope.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "large process pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "Mount the 65.088 mm bore 395A by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 65.088 mm bore (110×22 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "A single 395A cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Setting is a design value, not an assembly feel: excessive preload in the 395A pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The 790 g mass and 22 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 395A.", "The 108/118 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 395A (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 395 A/394 A designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 395A inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 395-series code marks the dimensional series. The metric dimensions 65.088×110×22 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 395A mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (395-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 395A take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 395A compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 395A position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 395A?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 22 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "395A-394A-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "395A-394A", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "395A-394A" ], "locale_variants": {} }, { "sku": "3984-3920", "brand": "SKF", "manufacturer_designation": "SKF 3984/3920", "series": "3900-series", "type": "tapered_roller", "d_mm": 65.088, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 152, "static_load_kN": 183, "fatigue_load_limit_kN": 21.2, "max_rpm": 5600, "reference_speed_rpm": 4800, "limiting_speed_rpm": 5600, "weight_g": 1150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Selection arithmetic: the C0/C ratio is about 1.20 (static 183 kN against dynamic 152 kN), typical of a tapered roller sized for axial capacity, and the 21.2 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 3984 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Cross-section geometry: the 23.8 mm half-section ((112.712−65.088)/2) of this 39800-series unit places the roller large-end pitch diameter at roughly 88 mm, and the 30.162 mm axial width is split between cone (17 mm) and cup rib (14 mm) — a geometry that sets the contact angle and, with the 1150 g rotating cone mass, the critical speed at which cage-roller imbalance begins. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 3984 the 3984 cone contributes the 65.088 mm bore and roller set, the 3920 cup contributes the 112.712 mm OD raceway, and the assembled 30.162 mm width is the catalogue value.In SKF catalogue PUB BU/P1 17000, 3984 appears as SKF 3984/3920: an open, single-row tapered roller bearing in the 3900-series, supplied with a pressed-steel cage as standard.Reading the designation: 3984 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 3900-series code identifies the dimensional series. The 65.088 mm bore, 112.712 mm OD and 30.162 mm width are the metric equivalents of the inch boundary dimensions.", "applications": [ "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "rolling-mill auxiliary drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Mount the 65.088 mm bore 3984 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 65.088 mm bore (112.712×30.162 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 3984 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "At the 152 kN rating of 3984, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 5,600 r/min speed end and heavier preload only where moment stiffness dominates.", "Open 3984 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 152/183 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 3984 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 3984/3920 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in 3984 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (3900-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 3984 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 3984 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 3984 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 3984?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 30.162 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 3984 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "3984-3925", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "3984-3920", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "3984-3920" ], "locale_variants": {} }, { "sku": "39590-39520", "brand": "SKF", "manufacturer_designation": "SKF 39590/39520", "series": "39500-series", "type": "tapered_roller", "d_mm": 65.088, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 175, "static_load_kN": 204, "fatigue_load_limit_kN": 23.6, "max_rpm": 5600, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5600, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Digit by digit, 39590 reads as cone reference / cup reference in the 39500-series inch series; the 65.088 mm bore, 112.712 mm OD and 30.162 mm width are the metric equivalents of the original inch boundary values. In SKF suffix language a bare 39590 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 23.6 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.17 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 39590 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Cross-section geometry: the 23.8 mm half-section ((112.712−65.088)/2) of this 39500-series unit places the roller large-end pitch diameter at roughly 88 mm, and the 30.162 mm axial width is split between cone (17 mm) and cup rib (14 mm) — a geometry that sets the contact angle and, with the 1200 g rotating cone mass, the critical speed at which cage-roller imbalance begins. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 39590 the 39590 cone contributes the 65.088 mm bore and roller set, the 39520 cup contributes the 112.712 mm OD raceway, and the assembled 30.162 mm width is the catalogue value.In SKF catalogue PUB BU/P1 17000, 39590 appears as SKF 39590/39520: an open, single-row tapered roller bearing in the 39500-series, supplied with a pressed-steel cage as standard.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "marine deck machinery shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Mount the 65.088 mm bore 39590 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 65.088 mm bore (112.712×30.162 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "Do not mix brands or executions inside one 39590 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 39590 mounting error.", "Catalogue reference speed and limiting speed are different limits: the 4,500 r/min reference is a thermal criterion under load, while the 5,600 r/min limiting value is the mechanical ceiling — observe both.", "The 175/204 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 39590 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 39590/39520 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 39590 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 39500-series code marks the dimensional series. The metric dimensions 65.088×112.712×30.162 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 39590 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (39500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 39590 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 39590 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 39590 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 39590?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 30.162 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "39590-39520-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "39590-39520", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "39590-39520" ], "locale_variants": {} }, { "sku": "39590-39528", "brand": "SKF", "manufacturer_designation": "SKF 39590/39528", "series": "39500-series", "type": "tapered_roller", "d_mm": 65.088, "D_mm": 119.985, "B_mm": 32.751, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 175, "static_load_kN": 204, "fatigue_load_limit_kN": 23.6, "max_rpm": 5600, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5600, "weight_g": 1550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Digit by digit, 39590 reads as cone reference / cup reference in the 39500-series inch series; the 65.088 mm bore, 119.985 mm OD and 32.751 mm width are the metric equivalents of the original inch boundary values. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 23.6 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.17 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 39590 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Cross-section geometry: the 27.4 mm half-section ((119.985−65.088)/2) of this 39500-series unit places the roller large-end pitch diameter at roughly 92 mm, and the 32.751 mm axial width is split between cone (18 mm) and cup rib (15 mm) — a geometry that sets the contact angle and, with the 1550 g rotating cone mass, the critical speed at which cage-roller imbalance begins. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 39590 the 39590 cone contributes the 65.088 mm bore and roller set, the 39528 cup contributes the 119.985 mm OD raceway, and the assembled 32.751 mm width is the catalogue value.In SKF catalogue PUB BU/P1 17000, 39590 appears as SKF 39590/39528: an open, single-row tapered roller bearing in the 39500-series, supplied with a pressed-steel cage as standard.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "marine deck machinery shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "Mount the 65.088 mm bore 39590 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 65.088 mm bore (119.985×32.751 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "Do not mix brands or executions inside one 39590 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 39590 mounting error.", "Catalogue reference speed and limiting speed are different limits: the 4,500 r/min reference is a thermal criterion under load, while the 5,600 r/min limiting value is the mechanical ceiling — observe both.", "The 175/204 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 39590 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 39590/39528 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 39590 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 39500-series code marks the dimensional series. The metric dimensions 65.088×119.985×32.751 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 39590 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (39500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 39590 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 39590 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 39590 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 39590?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 32.751 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "39590-39520-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "39590-39528", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "39590-39528" ], "locale_variants": {} }, { "sku": "HM212049-011", "brand": "SKF", "manufacturer_designation": "SKF HM 212049/011", "series": "HM212000-series", "type": "tapered_roller", "d_mm": 65.088, "D_mm": 122.238, "B_mm": 38.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 229, "static_load_kN": 245, "fatigue_load_limit_kN": 28, "max_rpm": 5300, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5300, "weight_g": 1850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " From a specification standpoint the 011 cup is the controlling half of HM212049 for housing design — it sets the 122.238 mm OD and the outer abutment diameter — while the HM 212049 cone controls shaft fit at the 65.088 mm bore; the 38.1 mm width is the result of the two together.SKF HM 212049/011 belongs to the SKF single-row tapered roller range — the 65.088 mm bore entry in the inch HM212000-series, dimensioned 122.238 mm OD and 38.1 mm wide.The HM212000-series series assigns 65.088 mm bore, 122.238 mm OD and 38.1 mm width to HM212049; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. In SKF suffix language a bare HM212049 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 28 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.07 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Because the contact line is tapered, one HM212049 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 65.088 mm shaft typically takes a k5 seat with an H7 housing bore. Dimensional interchange map: within the HM200 series at 65.088 mm bore, the 122.238 mm OD and 38.1 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 28.6 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 1850 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "paper-machine and printing rolls" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Mount the 65.088 mm bore HM212049 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The HM212000-series inch series at 65.088 mm bore (122.238×38.1 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common HM212049 mounting error.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HM212049 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Catalogue reference speed and limiting speed are different limits: the 4,500 r/min reference is a thermal criterion under load, while the 5,300 r/min limiting value is the mechanical ceiling — observe both.", "The 229/245 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM212049 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 212049/011 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is HM212049 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM212049?", "a": "The SKF HM 212049/011 is a single-row tapered roller bearing with 65.088 mm bore, 122.238 mm outer diameter and 38.1 mm width (2.563 × 4.813 × 1.5 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 229 kN, C0 245 kN, fatigue load limit Pu 28 kN, reference speed 4,500 r/min, limiting speed 5,300 r/min, mass about 1850 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM212049 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM212000-series code marks the dimensional series. The metric dimensions 65.088×122.238×38.1 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM212049 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM212000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single HM212049 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "HM212049-HM212010", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "HM212049-011", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM212049-011" ], "locale_variants": {} }, { "sku": "6386-K-6320", "brand": "SKF", "manufacturer_designation": "SKF 6386/K-6320", "series": "6300-series", "type": "tapered_roller", "d_mm": 65.088, "D_mm": 135.755, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 353, "static_load_kN": 400, "fatigue_load_limit_kN": 45.5, "max_rpm": 5000, "reference_speed_rpm": 4000, "limiting_speed_rpm": 5000, "weight_g": 3650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Speed planning uses two different ceilings: 4,000 r/min thermal reference and 5,000 r/min mechanical limiting speed. For a 65.088 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 6386 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Load system: the 353 kN basic dynamic rating C and 400 kN static rating C0 give a C0/C balance of 1.13, and dividing C by the 65.088 mm bore yields 5.42 kN per millimetre of journal — a density metric that compares across families; the 45.5 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 65.088 mm shaft carrying variable duty. The cup reference K-6320 is structural, not a suffix: it identifies the outer ring that, combined with the 6386 cone, produces the 65.088/135.755/53.975 mm envelope catalogue-listed as 6386. Quote the cup number in full when ordering — the 6300-series tables contain other cups that fit the same cone but change the bearing.Ordering number SKF 6386/K-6320 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 65.088 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.On the SKF nameplate, 6386 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 6300-series marking the dimensional series. In SKF suffix language a bare 6386 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately.", "applications": [ "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "paper-machine and printing rolls" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Mount the 65.088 mm bore 6386 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 6300-series inch series at 65.088 mm bore (135.755×53.975 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 6386 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 6386 mounting error.", "Open 6386 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 353/400 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 6386 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 6386/K-6320 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 6386 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 6386 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 6386 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 6386?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 53.975 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 6386 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 6386?", "a": "The SKF 6386/K-6320 is a single-row tapered roller bearing with 65.088 mm bore, 135.755 mm outer diameter and 53.975 mm width (2.563 × 5.345 × 2.125 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 353 kN, C0 400 kN, fatigue load limit Pu 45.5 kN, reference speed 4,000 r/min, limiting speed 5,000 r/min, mass about 3650 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "6386-6320", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "6386-K-6320", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "6386-K-6320" ], "locale_variants": {} }, { "sku": "29675-29620", "brand": "SKF", "manufacturer_designation": "SKF 29675/29620", "series": "29600-series", "type": "tapered_roller", "d_mm": 69.85, "D_mm": 112.712, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 121, "static_load_kN": 156, "fatigue_load_limit_kN": 17.6, "max_rpm": 5300, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5300, "weight_g": 970, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 29675/29620 belongs to the SKF single-row tapered roller range — the 69.85 mm bore entry in the inch 29600-series, dimensioned 112.712 mm OD and 25.4 mm wide.Digit by digit, 29675 reads as cone reference / cup reference in the 29600-series inch series; the 69.85 mm bore, 112.712 mm OD and 25.4 mm width are the metric equivalents of the original inch boundary values. In SKF suffix language a bare 29675 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 1.29 (static 156 kN against dynamic 121 kN), typical of a tapered roller sized for axial capacity, and the 17.6 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 29675 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Load system: the 121 kN basic dynamic rating C and 156 kN static rating C0 give a C0/C balance of 1.29, and dividing C by the 69.85 mm bore yields 1.73 kN per millimetre of journal — a density metric that compares across families; the 17.6 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 69.85 mm shaft carrying variable duty. Within the 29600-series tables, 29675 appears in several rows because SKF lists multiple cup options for the same cone. 29675 is the 29620 variant, with 112.712 mm OD and 25.4 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Mount the 69.85 mm bore 29675 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 29600-series inch series at 69.85 mm bore (112.712×25.4 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 29675 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "At the 121 kN rating of 29675, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 5,300 r/min speed end and heavier preload only where moment stiffness dominates.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 121/156 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 29675 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 29675/29620 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 29675?", "a": "The SKF 29675/29620 is a single-row tapered roller bearing with 69.85 mm bore, 112.712 mm outer diameter and 25.4 mm width (2.75 × 4.437 × 1 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 121 kN, C0 156 kN, fatigue load limit Pu 17.6 kN, reference speed 4,500 r/min, limiting speed 5,300 r/min, mass about 970 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 29675 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 29600-series code marks the dimensional series. The metric dimensions 69.85×112.712×25.4 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 29675 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (29600-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 29675 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 29675 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 29675 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "29675-29620-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 69.85×112.712×25.4 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "29675-29630", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "29675-29620", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "29675-29620" ], "locale_variants": {} }, { "sku": "482-472", "brand": "SKF", "manufacturer_designation": "SKF 482/472", "series": "475-series", "type": "tapered_roller", "d_mm": 69.85, "D_mm": 120, "B_mm": 29.795, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 163, "static_load_kN": 186, "fatigue_load_limit_kN": 21.6, "max_rpm": 5300, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5300, "weight_g": 1350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Because the contact line is tapered, one 482 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 69.85 mm shaft typically takes a k5 seat with an H7 housing bore. Material and manufacturing detail: the 1350 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 48200 ISO envelope, with the pressed-steel cage contributing roughly 41 g of the total; the 69.85 mm bore is ground to IT5 roundness and the 120 mm OD to IT5 cylindricity, and the 29.795 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Two catalogue entries share the 482 cone but use different cups; this one, 482, takes the 472 cup and is ground for the resulting 120 mm OD / 29.795 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.Ordering number SKF 482/472 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 69.85 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.On the SKF nameplate, 482 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 475-series marking the dimensional series. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. At 4,500 r/min reference speed the 25.1 mm-section 482 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 5,300 r/min as the mechanical ceiling.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "crane sheave and hoist gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Mount the 69.85 mm bore 482 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 475-series inch series at 69.85 mm bore (120×29.795 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 482 mounting error.", "A single 482 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The 1350 g mass and 29.795 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 482.", "The 163/186 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 482 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 482/472 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 482 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 482 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 482?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 29.795 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 482 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 482?", "a": "The SKF 482/472 is a single-row tapered roller bearing with 69.85 mm bore, 120 mm outer diameter and 29.795 mm width (2.75 × 4.724 × 1.173 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 163 kN, C0 186 kN, fatigue load limit Pu 21.6 kN, reference speed 4,500 r/min, limiting speed 5,300 r/min, mass about 1350 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 482 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 475-series code marks the dimensional series. The metric dimensions 69.85×120×29.795 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "482-472-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 69.85×120×29.795 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "482-472", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "482-472" ], "locale_variants": {} }, { "sku": "47487-47420", "brand": "SKF", "manufacturer_designation": "SKF 47487/47420", "series": "47400-series", "type": "tapered_roller", "d_mm": 69.85, "D_mm": 120, "B_mm": 32.545, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 188, "static_load_kN": 228, "fatigue_load_limit_kN": 26.5, "max_rpm": 5300, "reference_speed_rpm": 4300, "limiting_speed_rpm": 5300, "weight_g": 1500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 47487/47420 is a 69.85×120×32.545 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.Digit by digit, 47487 reads as cone reference / cup reference in the 47400-series inch series; the 69.85 mm bore, 120 mm OD and 32.545 mm width are the metric equivalents of the original inch boundary values. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Selection arithmetic: the C0/C ratio is about 1.21 (static 228 kN against dynamic 188 kN), typical of a tapered roller sized for axial capacity, and the 26.5 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Because the contact line is tapered, one 47487 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 69.85 mm shaft typically takes a k5 seat with an H7 housing bore. Journal and housing interface: the 69.85 mm bore takes a k5 shaft seat (upper deviation ~0.140 mm for this diameter range) and the 120 mm outside diameter pairs with an H7 housing bore tolerance band of 120.000/120.020 mm; the 32.545 mm width defines the shoulder depth, and the 1500 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Inch tapered bearings are matched sets, not mix-and-match components: 47487 pairs the 47487 cone with the 47420 cup under the 47400-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "Mount the 69.85 mm bore 47487 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 47400-series inch series at 69.85 mm bore (120×32.545 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 47487 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "At the 188 kN rating of 47487, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 5,300 r/min speed end and heavier preload only where moment stiffness dominates.", "Shaft and housing fillets must clear the bearing chamfer so the 32.545 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 188/228 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 47487 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 47487/47420 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 47487?", "a": "The SKF 47487/47420 is a single-row tapered roller bearing with 69.85 mm bore, 120 mm outer diameter and 32.545 mm width (2.75 × 4.724 × 1.281 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 188 kN, C0 228 kN, fatigue load limit Pu 26.5 kN, reference speed 4,300 r/min, limiting speed 5,300 r/min, mass about 1500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 47487 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 47400-series code marks the dimensional series. The metric dimensions 69.85×120×32.545 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 47487 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (47400-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 47487 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 47487 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 47487 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "47487-47420-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 69.85×120×32.545 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "47487-47420", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "47487-47420" ], "locale_variants": {} }, { "sku": "47487-47420A", "brand": "SKF", "manufacturer_designation": "SKF 47487/47420 A", "series": "47400-series", "type": "tapered_roller", "d_mm": 69.85, "D_mm": 120, "B_mm": 32.545, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 188, "static_load_kN": 228, "fatigue_load_limit_kN": 26.5, "max_rpm": 5300, "reference_speed_rpm": 4300, "limiting_speed_rpm": 5300, "weight_g": 1500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The 47400-series series assigns 69.85 mm bore, 120 mm OD and 32.545 mm width to 47487; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. In SKF suffix language a bare 47487 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 25.1 mm radial section height ((120−69.85)/2) and 1500 g catalogue mass frame a 69.85 mm bore bearing rated at 188 kN C — roughly 2.69 kN of dynamic capacity per millimetre of bore before application factors. Mounting practice for 47487: the rotating cone takes the interference fit (k5 on a 69.85 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Speed envelope and thermal behaviour: at 4,300 r/min thermal reference, the 69.85 mm bore shaft runs at a dn of 300k, and the 25.1 mm section dissipates heat through the cup-to-housing contact path; the 5,300 r/min mechanical ceiling reflects cage strength, and the 1500 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cone versus cup responsibility in 47487: the 47487 cone carries the 69.85 mm bore, rollers and pressed-steel cage; the 47420 A cup carries the 120 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.In SKF catalogue PUB BU/P1 17000, 47487 appears as SKF 47487/47420 A: an open, single-row tapered roller bearing in the 47400-series, supplied with a pressed-steel cage as standard.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "crane sheave and hoist gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Mount the 69.85 mm bore 47487 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 47400-series inch series at 69.85 mm bore (120×32.545 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 47487 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Setting is a design value, not an assembly feel: excessive preload in the 47487 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Open 47487 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 188/228 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 47487 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 47487/47420 A designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 47487 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 47400-series code marks the dimensional series. The metric dimensions 69.85×120×32.545 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 47487 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (47400-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 47487 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 47487 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 47487 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 47487?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 32.545 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "47487-47420-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 69.85×120×32.545 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "47487-47420A", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "47487-47420A" ], "locale_variants": {} }, { "sku": "566-563", "brand": "SKF", "manufacturer_designation": "SKF 566/563", "series": "565-series", "type": "tapered_roller", "d_mm": 69.85, "D_mm": 127, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 217, "static_load_kN": 255, "fatigue_load_limit_kN": 29, "max_rpm": 5000, "reference_speed_rpm": 4300, "limiting_speed_rpm": 5000, "weight_g": 1950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The 28.6 mm radial section height ((127−69.85)/2) and 1950 g catalogue mass frame a 69.85 mm bore bearing rated at 217 kN C — roughly 3.11 kN of dynamic capacity per millimetre of bore before application factors. Mounting practice for 566: the rotating cone takes the interference fit (k5 on a 69.85 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Load system: the 217 kN basic dynamic rating C and 255 kN static rating C0 give a C0/C balance of 1.18, and dividing C by the 69.85 mm bore yields 3.11 kN per millimetre of journal — a density metric that compares across families; the 29 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 69.85 mm shaft carrying variable duty. The cup reference 563 is structural, not a suffix: it identifies the outer ring that, combined with the 566 cone, produces the 69.85/127/36.512 mm envelope catalogue-listed as 566. Quote the cup number in full when ordering — the 565-series tables contain other cups that fit the same cone but change the bearing.566 is a single-row tapered roller bearing in the 565-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Numbering ties the bearing to its inch-series envelope: 566 means a cone and cup matched pair in the 565-series series — which is why the 69.85×127×36.512 mm outline swaps dimensionally with other inch-series bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "construction machinery drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Mount the 69.85 mm bore 566 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 565-series inch series at 69.85 mm bore (127×36.512 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 566 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 566 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Shaft and housing fillets must clear the bearing chamfer so the 36.512 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 217/255 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 566 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 566/563 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 566 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 566 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 566 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 566?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 36.512 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 566 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 566?", "a": "The SKF 566/563 is a single-row tapered roller bearing with 69.85 mm bore, 127 mm outer diameter and 36.512 mm width (2.75 × 5 × 1.437 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 217 kN, C0 255 kN, fatigue load limit Pu 29 kN, reference speed 4,300 r/min, limiting speed 5,000 r/min, mass about 1950 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "566-563-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 69.85×127×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "566-563", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "566-563" ], "locale_variants": {} }, { "sku": "655-652", "brand": "SKF", "manufacturer_designation": "SKF 655/652", "series": "655-series", "type": "tapered_roller", "d_mm": 69.85, "D_mm": 152.4, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 270, "static_load_kN": 320, "fatigue_load_limit_kN": 35.5, "max_rpm": 4300, "reference_speed_rpm": 3600, "limiting_speed_rpm": 4300, "weight_g": 3650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 41.3 mm radial section height ((152.4−69.85)/2) and 3650 g catalogue mass frame a 69.85 mm bore bearing rated at 270 kN C — roughly 3.87 kN of dynamic capacity per millimetre of bore before application factors. A single 655 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Speed envelope and thermal behaviour: at 3,600 r/min thermal reference, the 69.85 mm bore shaft runs at a dn of 251k, and the 41.3 mm section dissipates heat through the cup-to-housing contact path; the 4,300 r/min mechanical ceiling reflects cage strength, and the 3650 g spinning cone contributes gyroscopic moment under rapid speed reversal. Why the cup reference matters here: in the 655-series tables the 655 cone appears against several cup options. 655 is the pairing with 652, and that choice — not the cone — fixes the 152.4 mm OD, the raceway track position and the 41.275 mm assembled width.For a 69.85 mm shaft carrying combined load, SKF lists 655 under catalogue execution SKF 655/652: one open single-row tapered roller bearing in the inch 655-series.In SKF inch-series tables 655 sits at 69.85 mm bore (2.75 in) with a 152.4 mm cup OD and 41.275 mm total width — dimensions that trace back to the original Timken boundary plan for the 655-series family.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "paper-machine and printing rolls" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Mount the 69.85 mm bore 655 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 655-series inch series at 69.85 mm bore (152.4×41.275 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 655 mounting error.", "At the 270 kN rating of 655, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 4,300 r/min speed end and heavier preload only where moment stiffness dominates.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 152.4 mm cup race release as noise within the first running hours.", "The 270/320 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 655 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 655/652 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in 655 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (655-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 655 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 655 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 655 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 655?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 41.275 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 655 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "655-653", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "655-652", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "655-652" ], "locale_variants": {} }, { "sku": "33281-33462", "brand": "SKF", "manufacturer_designation": "SKF 33281/33462", "series": "33000-series", "type": "tapered_roller", "d_mm": 71.438, "D_mm": 117.475, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 152, "static_load_kN": 190, "fatigue_load_limit_kN": 21.6, "max_rpm": 5300, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5300, "weight_g": 1250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "On the SKF nameplate, 33281 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 33000-series marking the dimensional series. In SKF suffix language a bare 33281 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 23.0 mm radial section height ((117.475−71.438)/2) and 1250 g catalogue mass frame a 71.438 mm bore bearing rated at 152 kN C — roughly 2.13 kN of dynamic capacity per millimetre of bore before application factors. For a 71.438 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 33281 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Cross-section geometry: the 23.0 mm half-section ((117.475−71.438)/2) of this 33200-series unit places the roller large-end pitch diameter at roughly 94 mm, and the 30.162 mm axial width is split between cone (17 mm) and cup rib (14 mm) — a geometry that sets the contact angle and, with the 1250 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Why the cup reference matters here: in the 33000-series tables the 33281 cone appears against several cup options. 33281 is the pairing with 33462, and that choice — not the cone — fixes the 117.475 mm OD, the raceway track position and the 30.162 mm assembled width.Ordering number SKF 33281/33462 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 71.438 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "crane sheave and hoist gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Mount the 71.438 mm bore 33281 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 332 series at 71.438 mm bore (117.475×30.162 mm) is the wide medium-section choice — more capacity than 302 in the same OD class but a wider footprint; re-check housing width and pair setting before substituting.", "Setting is a design value, not an assembly feel: excessive preload in the 33281 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 33281 mounting error.", "The 33281 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 152/190 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 33281 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 33281/33462 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 33281 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 33000-series code marks the dimensional series. The metric dimensions 71.438×117.475×30.162 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 33281 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (33000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 33281 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 33281 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 33281 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 33281?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 30.162 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "33281-33462-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 71.438×117.475×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "33281-33462", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "33281-33462" ], "locale_variants": {} }, { "sku": "H715345-311", "brand": "SKF", "manufacturer_designation": "SKF H 715345/311", "series": "H715300-series", "type": "tapered_roller", "d_mm": 71.438, "D_mm": 136.525, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 273, "static_load_kN": 355, "fatigue_load_limit_kN": 39, "max_rpm": 4500, "reference_speed_rpm": 3800, "limiting_speed_rpm": 4500, "weight_g": 3100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Digit by digit, H715345 reads as cone reference / cup reference in the H715300-series inch series; the 71.438 mm bore, 136.525 mm OD and 46.038 mm width are the metric equivalents of the original inch boundary values. In SKF suffix language a bare H715345 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Speed planning uses two different ceilings: 3,800 r/min thermal reference and 4,500 r/min mechanical limiting speed. For a 71.438 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two H715345 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Journal and housing interface: the 71.438 mm bore takes a k5 shaft seat (upper deviation ~0.143 mm for this diameter range) and the 136.525 mm outside diameter pairs with an H7 housing bore tolerance band of 136.525.000/136.545 mm; the 46.038 mm width defines the shoulder depth, and the 3100 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Two catalogue entries share the H 715345 cone but use different cups; this one, H715345, takes the 311 cup and is ground for the resulting 136.525 mm OD / 46.038 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.The SKF H 715345/311 is a 71.438×136.525×46.038 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "rolling-mill auxiliary drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "Mount the 71.438 mm bore H715345 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The H715300-series inch series at 71.438 mm bore (136.525×46.038 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one H715345 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the H715345 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The 3100 g mass and 46.038 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of H715345.", "The 273/355 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of H715345 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF H 715345/311 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the H715345 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the H715300-series code marks the dimensional series. The metric dimensions 71.438×136.525×46.038 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in H715345 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (H715300-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single H715345 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does H715345 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load H715345 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit H715345?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 46.038 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "H715345-H715311", "equiv_brand": "NTN", "level": "partial", "note": "Same 71.438×136.525×46.038 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "H715345-311", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "H715345-311" ], "locale_variants": {} }, { "sku": "29685-29620", "brand": "SKF", "manufacturer_designation": "SKF 29685/29620", "series": "29600-series", "type": "tapered_roller", "d_mm": 73.025, "D_mm": 112.712, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 121, "static_load_kN": 156, "fatigue_load_limit_kN": 17.6, "max_rpm": 5300, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5300, "weight_g": 890, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF 29685/29620 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 73.025 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.The 29600-series series assigns 73.025 mm bore, 112.712 mm OD and 25.4 mm width to 29685; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Speed planning uses two different ceilings: 4,500 r/min thermal reference and 5,300 r/min mechanical limiting speed. A single 29685 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Load system: the 121 kN basic dynamic rating C and 156 kN static rating C0 give a C0/C balance of 1.29, and dividing C by the 73.025 mm bore yields 1.66 kN per millimetre of journal — a density metric that compares across families; the 17.6 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 73.025 mm shaft carrying variable duty. Within the 29600-series tables, 29685 appears in several rows because SKF lists multiple cup options for the same cone. 29685 is the 29620 variant, with 112.712 mm OD and 25.4 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "large process pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "Mount the 73.025 mm bore 29685 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 29600-series inch series at 73.025 mm bore (112.712×25.4 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 121 kN rating of 29685, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 5,300 r/min speed end and heavier preload only where moment stiffness dominates.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 29685 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The 29685 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 121/156 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 29685 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 29685/29620 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 29685?", "a": "The SKF 29685/29620 is a single-row tapered roller bearing with 73.025 mm bore, 112.712 mm outer diameter and 25.4 mm width (2.875 × 4.437 × 1 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 121 kN, C0 156 kN, fatigue load limit Pu 17.6 kN, reference speed 4,500 r/min, limiting speed 5,300 r/min, mass about 890 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 29685 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 29600-series code marks the dimensional series. The metric dimensions 73.025×112.712×25.4 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 29685 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (29600-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 29685 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 29685 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 29685 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "29685-29620-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 73.025×112.712×25.4 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "29685-29620", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "29685-29620" ], "locale_variants": {} }, { "sku": "33287-33462", "brand": "SKF", "manufacturer_designation": "SKF 33287/33462", "series": "33000-series", "type": "tapered_roller", "d_mm": 73.025, "D_mm": 117.475, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 152, "static_load_kN": 190, "fatigue_load_limit_kN": 21.6, "max_rpm": 5300, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5300, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Specify pairs rather than single units wherever thrust reverses: the tapered contact of 33287 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Speed envelope and thermal behaviour: at 4,500 r/min thermal reference, the 73.025 mm bore shaft runs at a dn of 329k, and the 22.2 mm section dissipates heat through the cup-to-housing contact path; the 5,300 r/min mechanical ceiling reflects cage strength, and the 1200 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cone versus cup responsibility in 33287: the 33287 cone carries the 73.025 mm bore, rollers and pressed-steel cage; the 33462 cup carries the 117.475 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.The SKF 33287/33462 is a 73.025×117.475×30.162 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (33000-series) ties the pair to a specific boundary plan. Dimensions 73.025×117.475×30.162 mm are the converted metric envelope. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. At 4,500 r/min reference speed the 22.2 mm-section 33287 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 5,300 r/min as the mechanical ceiling.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "crane sheave and hoist gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Mount the 73.025 mm bore 33287 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 332 series at 73.025 mm bore (117.475×30.162 mm) is the wide medium-section choice — more capacity than 302 in the same OD class but a wider footprint; re-check housing width and pair setting before substituting.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 33287 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 33287 mounting error.", "The 1200 g mass and 30.162 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 33287.", "The 152/190 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 33287 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 33287/33462 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 33287 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 33287 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 33287?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 30.162 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 33287 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 33287?", "a": "The SKF 33287/33462 is a single-row tapered roller bearing with 73.025 mm bore, 117.475 mm outer diameter and 30.162 mm width (2.875 × 4.625 × 1.187 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 152 kN, C0 190 kN, fatigue load limit Pu 21.6 kN, reference speed 4,500 r/min, limiting speed 5,300 r/min, mass about 1200 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 33287 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 33000-series code marks the dimensional series. The metric dimensions 73.025×117.475×30.162 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "33287-33462-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 73.025×117.475×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "33287-33462", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "33287-33462" ], "locale_variants": {} }, { "sku": "567-563", "brand": "SKF", "manufacturer_designation": "SKF 567/563", "series": "565-series", "type": "tapered_roller", "d_mm": 73.025, "D_mm": 127, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 217, "static_load_kN": 255, "fatigue_load_limit_kN": 29, "max_rpm": 5000, "reference_speed_rpm": 4300, "limiting_speed_rpm": 5000, "weight_g": 1850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Material and manufacturing detail: the 1850 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 56700 ISO envelope, with the pressed-steel cage contributing roughly 56 g of the total; the 73.025 mm bore is ground to IT5 roundness and the 127 mm OD to IT5 cylindricity, and the 36.512 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Housing and abutment design flows from the cup: in 567 the 563 cup fixes the 127 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the 567 cone determines the 73.025 mm shaft interface; the 36.512 mm width is the assembled pair value.SKF 567/563 belongs to the SKF single-row tapered roller range — the 73.025 mm bore entry in the inch 565-series, dimensioned 127 mm OD and 36.512 mm wide.On the SKF nameplate, 567 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 565-series marking the dimensional series. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Speed planning uses two different ceilings: 4,300 r/min thermal reference and 5,000 r/min mechanical limiting speed. Because the contact line is tapered, one 567 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 73.025 mm shaft typically takes a k5 seat with an H7 housing bore.", "applications": [ "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Mount the 73.025 mm bore 567 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 565-series inch series at 73.025 mm bore (127×36.512 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 217 kN rating of 567, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 5,000 r/min speed end and heavier preload only where moment stiffness dominates.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 567 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Open 567 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 217/255 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 567 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 567/563 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 567?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 36.512 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 567 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 567?", "a": "The SKF 567/563 is a single-row tapered roller bearing with 73.025 mm bore, 127 mm outer diameter and 36.512 mm width (2.875 × 5 × 1.437 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 217 kN, C0 255 kN, fatigue load limit Pu 29 kN, reference speed 4,300 r/min, limiting speed 5,000 r/min, mass about 1850 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 567 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 565-series code marks the dimensional series. The metric dimensions 73.025×127×36.512 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 567 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (565-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "567-563-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 73.025×127×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "567-563", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "567-563" ], "locale_variants": {} }, { "sku": "HM215249-210", "brand": "SKF", "manufacturer_designation": "SKF HM 215249/210", "series": "HM215200-series", "type": "tapered_roller", "d_mm": 76, "D_mm": 132, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 255, "static_load_kN": 305, "fatigue_load_limit_kN": 34.5, "max_rpm": 4800, "reference_speed_rpm": 4000, "limiting_speed_rpm": 4800, "weight_g": 2150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Reading the designation: HM215249 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the HM215200-series code identifies the dimensional series. The 76 mm bore, 132 mm OD and 39 mm width are the metric equivalents of the inch boundary dimensions. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 255 kN and C0 305 kN, the HM215249 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 4,800 r/min. Mounting practice for HM215249: the rotating cone takes the interference fit (k5 on a 76 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Load system: the 255 kN basic dynamic rating C and 305 kN static rating C0 give a C0/C balance of 1.20, and dividing C by the 76 mm bore yields 3.36 kN per millimetre of journal — a density metric that compares across families; the 34.5 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 76 mm shaft carrying variable duty. Cup-side note for 210: the outer ring's rib profile and the 132 mm outside diameter are cup-specific within the HM215200-series tables, so substituting a different cup against the same HM 215249 cone changes both the assembled 39 mm width and the axial free-play setting of the mounted pair.SKF HM 215249/210 belongs to the SKF single-row tapered roller range — the 76 mm bore entry in the inch HM215200-series, dimensioned 132 mm OD and 39 mm wide.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "paper-machine and printing rolls" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Mount the 76 mm bore HM215249 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The HM215200-series inch series at 76 mm bore (132×39 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HM215249 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Do not mix brands or executions inside one HM215249 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 255/305 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM215249 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 215249/210 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the HM215249 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM215200-series code marks the dimensional series. The metric dimensions 76×132×39 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM215249 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM215200-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single HM215249 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HM215249 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM215249 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HM215249?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 39 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "HM215249-210", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM215249-210" ], "locale_variants": {} }, { "sku": "L814749-710", "brand": "SKF", "manufacturer_designation": "SKF L 814749/710", "series": "L814700-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 109.538, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 72.1, "static_load_kN": 102, "fatigue_load_limit_kN": 11, "max_rpm": 5600, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5600, "weight_g": 570, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Cup-side note for 710: the outer ring's rib profile and the 109.538 mm outside diameter are cup-specific within the L814700-series tables, so substituting a different cup against the same L 814749 cone changes both the assembled 19.05 mm width and the axial free-play setting of the mounted pair.The SKF L 814749/710 is a 76.2×109.538×19.05 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.Numbering ties the bearing to its inch-series envelope: L814749 means a cone and cup matched pair in the L814700-series series — which is why the 76.2×109.538×19.05 mm outline swaps dimensionally with other inch-series bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Speed planning uses two different ceilings: 4,500 r/min thermal reference and 5,600 r/min mechanical limiting speed. Specify pairs rather than single units wherever thrust reverses: the tapered contact of L814749 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Load system: the 72.1 kN basic dynamic rating C and 102 kN static rating C0 give a C0/C balance of 1.41, and dividing C by the 76.2 mm bore yields 0.95 kN per millimetre of journal — a density metric that compares across families; the 11 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 76.2 mm shaft carrying variable duty.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Mount the 76.2 mm bore L814749 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The L814700-series inch series at 76.2 mm bore (109.538×19.05 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single L814749 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common L814749 mounting error.", "The L814749 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 72.1/102 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of L814749 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF L 814749/710 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is L814749 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of L814749?", "a": "The SKF L 814749/710 is a single-row tapered roller bearing with 76.2 mm bore, 109.538 mm outer diameter and 19.05 mm width (3 × 4.313 × 0.75 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 72.1 kN, C0 102 kN, fatigue load limit Pu 11 kN, reference speed 4,500 r/min, limiting speed 5,600 r/min, mass about 570 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the L814749 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the L814700-series code marks the dimensional series. The metric dimensions 76.2×109.538×19.05 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in L814749 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (L814700-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single L814749 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "L814749-L814710", "equiv_brand": "NTN", "level": "partial", "note": "Same 76.2×109.538×19.05 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "L814749-710", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "L814749-710" ], "locale_variants": {} }, { "sku": "42687-42620", "brand": "SKF", "manufacturer_designation": "SKF 42687/42620", "series": "42600-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 127, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 171, "static_load_kN": 204, "fatigue_load_limit_kN": 24, "max_rpm": 5000, "reference_speed_rpm": 4000, "limiting_speed_rpm": 5000, "weight_g": 1450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Catalogue mass 1450 g for the 76.2×127×30.162 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Fit selection follows the rotating ring — interference on a rotating cone — and two 42687 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Speed envelope and thermal behaviour: at 4,000 r/min thermal reference, the 76.2 mm bore shaft runs at a dn of 305k, and the 25.4 mm section dissipates heat through the cup-to-housing contact path; the 5,000 r/min mechanical ceiling reflects cage strength, and the 1450 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cup-side note for 42620: the outer ring's rib profile and the 127 mm outside diameter are cup-specific within the 42600-series tables, so substituting a different cup against the same 42687 cone changes both the assembled 30.162 mm width and the axial free-play setting of the mounted pair.SKF 42687/42620 belongs to the SKF single-row tapered roller range — the 76.2 mm bore entry in the inch 42600-series, dimensioned 127 mm OD and 30.162 mm wide.Reading the designation: 42687 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 42600-series code identifies the dimensional series. The 76.2 mm bore, 127 mm OD and 30.162 mm width are the metric equivalents of the inch boundary dimensions.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "marine deck machinery shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Mount the 76.2 mm bore 42687 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 42600-series inch series at 76.2 mm bore (127×30.162 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 42687 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "A single 42687 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The 42687 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 171/204 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 42687 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 42687/42620 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in 42687 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (42600-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 42687 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 42687 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 42687 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 42687?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 30.162 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 42687 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "42687-42620-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 76.2×127×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "42687-42620", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "42687-42620" ], "locale_variants": {} }, { "sku": "47678-47620", "brand": "SKF", "manufacturer_designation": "SKF 47678/47620", "series": "47600-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 133.35, "B_mm": 33.338, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 202, "static_load_kN": 260, "fatigue_load_limit_kN": 30, "max_rpm": 4800, "reference_speed_rpm": 3800, "limiting_speed_rpm": 4800, "weight_g": 1950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " With C 202 kN and C0 260 kN, the 47678 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 4,800 r/min. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 47678 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Speed envelope and thermal behaviour: at 3,800 r/min thermal reference, the 76.2 mm bore shaft runs at a dn of 290k, and the 28.6 mm section dissipates heat through the cup-to-housing contact path; the 4,800 r/min mechanical ceiling reflects cage strength, and the 1950 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cone versus cup responsibility in 47678: the 47678 cone carries the 76.2 mm bore, rollers and pressed-steel cage; the 47620 cup carries the 133.35 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.Ordering number SKF 47678/47620 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 76.2 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.Digit by digit, 47678 reads as cone reference / cup reference in the 47600-series inch series; the 76.2 mm bore, 133.35 mm OD and 33.338 mm width are the metric equivalents of the original inch boundary values. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "marine deck machinery shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "Mount the 76.2 mm bore 47678 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 47600-series inch series at 76.2 mm bore (133.35×33.338 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 47678 mounting error.", "Setting is a design value, not an assembly feel: excessive preload in the 47678 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 202/260 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 47678 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 47678/47620 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 47678 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 47678 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 47678 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 47678?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 33.338 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 47678 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 47678?", "a": "The SKF 47678/47620 is a single-row tapered roller bearing with 76.2 mm bore, 133.35 mm outer diameter and 33.338 mm width (3 × 5.25 × 1.313 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 202 kN, C0 260 kN, fatigue load limit Pu 30 kN, reference speed 3,800 r/min, limiting speed 4,800 r/min, mass about 1950 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "47678-47620-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 76.2×133.35×33.338 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "47678-47620", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "47678-47620" ], "locale_variants": {} }, { "sku": "575-572", "brand": "SKF", "manufacturer_designation": "SKF 575/572", "series": "575-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 139.992, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 227, "static_load_kN": 280, "fatigue_load_limit_kN": 31, "max_rpm": 4500, "reference_speed_rpm": 3800, "limiting_speed_rpm": 4500, "weight_g": 2450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Dimensional interchange map: within the 57500 series at 76.2 mm bore, the 139.992 mm OD and 36.512 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 31.9 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 2450 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. From a specification standpoint the 572 cup is the controlling half of 575 for housing design — it sets the 139.992 mm OD and the outer abutment diameter — while the 575 cone controls shaft fit at the 76.2 mm bore; the 36.512 mm width is the result of the two together.For a 76.2 mm shaft carrying combined load, SKF lists 575 under catalogue execution SKF 575/572: one open single-row tapered roller bearing in the inch 575-series.On the SKF nameplate, 575 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 575-series marking the dimensional series. In SKF suffix language a bare 575 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 31 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.23 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. A single 575 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Mount the 76.2 mm bore 575 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 575-series inch series at 76.2 mm bore (139.992×36.512 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 227 kN rating of 575, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 4,500 r/min speed end and heavier preload only where moment stiffness dominates.", "At the 227 kN rating of 575, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 4,500 r/min speed end and heavier preload only where moment stiffness dominates.", "The 575 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 227/280 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 575 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 575/572 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 575?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 36.512 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 575 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 575?", "a": "The SKF 575/572 is a single-row tapered roller bearing with 76.2 mm bore, 139.992 mm outer diameter and 36.512 mm width (3 × 5.511 × 1.437 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 227 kN, C0 280 kN, fatigue load limit Pu 31 kN, reference speed 3,800 r/min, limiting speed 4,500 r/min, mass about 2450 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 575 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 575-series code marks the dimensional series. The metric dimensions 76.2×139.992×36.512 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 575 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (575-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "575-572-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 76.2×139.992×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "575-572", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "575-572" ], "locale_variants": {} }, { "sku": "9285-9220", "brand": "SKF", "manufacturer_designation": "SKF 9285/9220", "series": "9200-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 161.925, "B_mm": 49.212, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 318, "static_load_kN": 335, "fatigue_load_limit_kN": 38, "max_rpm": 4000, "reference_speed_rpm": 3000, "limiting_speed_rpm": 4000, "weight_g": 4400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Dimensional interchange map: within the 92800 series at 76.2 mm bore, the 161.925 mm OD and 49.212 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 42.9 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 4400 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. From a specification standpoint the 9220 cup is the controlling half of 9285 for housing design — it sets the 161.925 mm OD and the outer abutment diameter — while the 9285 cone controls shaft fit at the 76.2 mm bore; the 49.212 mm width is the result of the two together.Ordering number SKF 9285/9220 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 76.2 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.Digit by digit, 9285 reads as cone reference / cup reference in the 9200-series inch series; the 76.2 mm bore, 161.925 mm OD and 49.212 mm width are the metric equivalents of the original inch boundary values. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 318 kN and C0 335 kN, the 9285 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 4,000 r/min. For a 76.2 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 9285 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel.", "applications": [ "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "Mount the 76.2 mm bore 9285 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 9200-series inch series at 76.2 mm bore (161.925×49.212 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 9285 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 9285 mounting error.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 161.925 mm cup race release as noise within the first running hours.", "The 318/335 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 9285 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 9285/9220 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 9285?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 49.212 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 9285 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 9285?", "a": "The SKF 9285/9220 is a single-row tapered roller bearing with 76.2 mm bore, 161.925 mm outer diameter and 49.212 mm width (3 × 6.375 × 1.937 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 318 kN, C0 335 kN, fatigue load limit Pu 38 kN, reference speed 3,000 r/min, limiting speed 4,000 r/min, mass about 4400 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 9285 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 9200-series code marks the dimensional series. The metric dimensions 76.2×161.925×49.212 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 9285 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (9200-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "9285-9220", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "9285-9220" ], "locale_variants": {} }, { "sku": "34306-34478", "brand": "SKF", "manufacturer_designation": "SKF 34306/34478", "series": "34000-series", "type": "tapered_roller", "d_mm": 77.788, "D_mm": 121.442, "B_mm": 24.608, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 115, "static_load_kN": 134, "fatigue_load_limit_kN": 15.3, "max_rpm": 5300, "reference_speed_rpm": 4300, "limiting_speed_rpm": 5300, "weight_g": 920, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Fit selection follows the rotating ring — interference on a rotating cone — and two 34306 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Material and manufacturing detail: the 920 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 34300 ISO envelope, with the pressed-steel cage contributing roughly 28 g of the total; the 77.788 mm bore is ground to IT5 roundness and the 121.442 mm OD to IT5 cylindricity, and the 24.608 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Cone versus cup responsibility in 34306: the 34306 cone carries the 77.788 mm bore, rollers and pressed-steel cage; the 34478 cup carries the 121.442 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.For a 77.788 mm shaft carrying combined load, SKF lists 34306 under catalogue execution SKF 34306/34478: one open single-row tapered roller bearing in the inch 34000-series.Digit by digit, 34306 reads as cone reference / cup reference in the 34000-series inch series; the 77.788 mm bore, 121.442 mm OD and 24.608 mm width are the metric equivalents of the original inch boundary values. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Selection arithmetic: the C0/C ratio is about 1.17 (static 134 kN against dynamic 115 kN), typical of a tapered roller sized for axial capacity, and the 15.3 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation.", "applications": [ "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives", "paper-machine and printing rolls" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Mount the 77.788 mm bore 34306 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 77.788 mm bore (121.442×24.608 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "At the 115 kN rating of 34306, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 5,300 r/min speed end and heavier preload only where moment stiffness dominates.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 34306 mounting error.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 115/134 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 34306 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 34306/34478 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 34306 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 34306 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 34306?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 24.608 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 34306 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 34306?", "a": "The SKF 34306/34478 is a single-row tapered roller bearing with 77.788 mm bore, 121.442 mm outer diameter and 24.608 mm width (3.063 × 4.781 × 0.969 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 115 kN, C0 134 kN, fatigue load limit Pu 15.3 kN, reference speed 4,300 r/min, limiting speed 5,300 r/min, mass about 920 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 34306 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 34000-series code marks the dimensional series. The metric dimensions 77.788×121.442×24.608 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "34306-34478-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 77.788×121.442×24.608 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "34306-34478", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "34306-34478" ], "locale_variants": {} }, { "sku": "42690-42620", "brand": "SKF", "manufacturer_designation": "SKF 42690/42620", "series": "42600-series", "type": "tapered_roller", "d_mm": 77.788, "D_mm": 127, "B_mm": 30.163, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 171, "static_load_kN": 204, "fatigue_load_limit_kN": 24, "max_rpm": 5000, "reference_speed_rpm": 4000, "limiting_speed_rpm": 5000, "weight_g": 1400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Two catalogue entries share the 42690 cone but use different cups; this one, 42690, takes the 42620 cup and is ground for the resulting 127 mm OD / 30.163 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.SKF 42690/42620 belongs to the SKF single-row tapered roller range — the 77.788 mm bore entry in the inch 42600-series, dimensioned 127 mm OD and 30.163 mm wide.The 42600-series series assigns 77.788 mm bore, 127 mm OD and 30.163 mm width to 42690; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. In SKF suffix language a bare 42690 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 4,000 r/min reference speed the 24.6 mm-section 42690 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 5,000 r/min as the mechanical ceiling. Fit selection follows the rotating ring — interference on a rotating cone — and two 42690 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Dimensional interchange map: within the 42600 series at 77.788 mm bore, the 127 mm OD and 30.163 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 24.6 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 1400 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "construction machinery drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Mount the 77.788 mm bore 42690 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 42600-series inch series at 77.788 mm bore (127×30.163 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 42690 mounting error.", "A single 42690 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 127 mm cup race release as noise within the first running hours.", "The 171/204 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 42690 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 42690/42620 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 42690 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 42690?", "a": "The SKF 42690/42620 is a single-row tapered roller bearing with 77.788 mm bore, 127 mm outer diameter and 30.163 mm width (3.063 × 5 × 1.188 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 171 kN, C0 204 kN, fatigue load limit Pu 24 kN, reference speed 4,000 r/min, limiting speed 5,000 r/min, mass about 1400 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 42690 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 42600-series code marks the dimensional series. The metric dimensions 77.788×127×30.163 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 42690 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (42600-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 42690 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "42690-42620-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 77.788×127×30.163 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "42690-42620", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "42690-42620" ], "locale_variants": {} }, { "sku": "580-572", "brand": "SKF", "manufacturer_designation": "SKF 580/572", "series": "575-series", "type": "tapered_roller", "d_mm": 82.55, "D_mm": 139.992, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 227, "static_load_kN": 280, "fatigue_load_limit_kN": 31, "max_rpm": 4500, "reference_speed_rpm": 3800, "limiting_speed_rpm": 4500, "weight_g": 2200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " At 3,800 r/min reference speed the 28.7 mm-section 580 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 4,500 r/min as the mechanical ceiling. For a 82.55 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 580 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Operating context for the 82.55 mm bore: a shaft of this diameter in the large-bore band typically runs between 66040 and 99060 r/min in real machinery, and the 139.992 mm outside diameter places the housing shoulder at 148 mm outer abutment; the 36.512 mm width and 2200 g mass together set the shaft critical speed and the housing resonance check for this 58000-series envelope. Two catalogue entries share the 580 cone but use different cups; this one, 580, takes the 572 cup and is ground for the resulting 139.992 mm OD / 36.512 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.580 is a single-row tapered roller bearing in the 575-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.On the SKF nameplate, 580 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 575-series marking the dimensional series. In SKF suffix language a bare 580 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately.", "applications": [ "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives", "rolling-mill auxiliary drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "Mount the 82.55 mm bore 580 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 575-series inch series at 82.55 mm bore (139.992×36.512 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 580 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "At the 227 kN rating of 580, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 4,500 r/min speed end and heavier preload only where moment stiffness dominates.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 227/280 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 580 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 580/572 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 580 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 580 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 580 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 580?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 36.512 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 580 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 580?", "a": "The SKF 580/572 is a single-row tapered roller bearing with 82.55 mm bore, 139.992 mm outer diameter and 36.512 mm width (3.25 × 5.511 × 1.437 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 227 kN, C0 280 kN, fatigue load limit Pu 31 kN, reference speed 3,800 r/min, limiting speed 4,500 r/min, mass about 2200 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "580-572-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 82.55×139.992×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "580-572", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "580-572" ], "locale_variants": {} }, { "sku": "663-653", "brand": "SKF", "manufacturer_designation": "SKF 663/653", "series": "655-series", "type": "tapered_roller", "d_mm": 82.55, "D_mm": 146.05, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 270, "static_load_kN": 320, "fatigue_load_limit_kN": 35.5, "max_rpm": 4300, "reference_speed_rpm": 3600, "limiting_speed_rpm": 4300, "weight_g": 2800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Speed envelope and thermal behaviour: at 3,600 r/min thermal reference, the 82.55 mm bore shaft runs at a dn of 297k, and the 31.8 mm section dissipates heat through the cup-to-housing contact path; the 4,300 r/min mechanical ceiling reflects cage strength, and the 2800 g spinning cone contributes gyroscopic moment under rapid speed reversal. Within the 655-series tables, 663 appears in several rows because SKF lists multiple cup options for the same cone. 663 is the 653 variant, with 146.05 mm OD and 41.275 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.The SKF 663/653 is a 82.55×146.05×41.275 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.On the SKF nameplate, 663 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 655-series marking the dimensional series. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. The 35.5 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.19 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Because the contact line is tapered, one 663 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 82.55 mm shaft typically takes a k5 seat with an H7 housing bore.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "Mount the 82.55 mm bore 663 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 655-series inch series at 82.55 mm bore (146.05×41.275 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 270 kN rating of 663, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 4,300 r/min speed end and heavier preload only where moment stiffness dominates.", "At the 270 kN rating of 663, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 4,300 r/min speed end and heavier preload only where moment stiffness dominates.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 146.05 mm cup race release as noise within the first running hours.", "The 270/320 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 663 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 663/653 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 663?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 41.275 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 663 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 663?", "a": "The SKF 663/653 is a single-row tapered roller bearing with 82.55 mm bore, 146.05 mm outer diameter and 41.275 mm width (3.25 × 5.75 × 1.625 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 270 kN, C0 320 kN, fatigue load limit Pu 35.5 kN, reference speed 3,600 r/min, limiting speed 4,300 r/min, mass about 2800 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 663 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 655-series code marks the dimensional series. The metric dimensions 82.55×146.05×41.275 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 663 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (655-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "663-652", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "663-653-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 82.55×146.05×41.275 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "663-653", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "663-653" ], "locale_variants": {} }, { "sku": "749A-742", "brand": "SKF", "manufacturer_designation": "SKF 749 A/742", "series": "745-series", "type": "tapered_roller", "d_mm": 82.55, "D_mm": 150.089, "B_mm": 44.45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 351, "static_load_kN": 405, "fatigue_load_limit_kN": 46.5, "max_rpm": 4300, "reference_speed_rpm": 3600, "limiting_speed_rpm": 4300, "weight_g": 3400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 46.5 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.15 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 749A generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Dimensional interchange map: within the 74900 series at 82.55 mm bore, the 150.089 mm OD and 44.45 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 33.8 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 3400 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Within the 745-series tables, 749 A appears in several rows because SKF lists multiple cup options for the same cone. 749A is the 742 variant, with 150.089 mm OD and 44.45 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.SKF 749A (SKF 749 A/742) is the 745-series tapered roller choice for a 82.55 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 150.089×44.45 mm envelope.The 745-series series assigns 82.55 mm bore, 150.089 mm OD and 44.45 mm width to 749A; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific.", "applications": [ "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Mount the 82.55 mm bore 749A by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 745-series inch series at 82.55 mm bore (150.089×44.45 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 749A pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Setting is a design value, not an assembly feel: excessive preload in the 749A pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Shaft and housing fillets must clear the bearing chamfer so the 44.45 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 351/405 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 749A (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 749 A/742 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in 749A mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (745-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 749A take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 749A compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 749A position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 749A?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 44.45 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 749A interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "749A-742-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 82.55×150.089×44.45 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "749A-742", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "749A-742" ], "locale_variants": {} }, { "sku": "497-492A", "brand": "SKF", "manufacturer_designation": "SKF 497/492 A", "series": "495-series", "type": "tapered_roller", "d_mm": 85.725, "D_mm": 133.35, "B_mm": 30.163, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 178, "static_load_kN": 220, "fatigue_load_limit_kN": 25.5, "max_rpm": 4500, "reference_speed_rpm": 3800, "limiting_speed_rpm": 4500, "weight_g": 1450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. At 3,800 r/min reference speed the 23.8 mm-section 497 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 4,500 r/min as the mechanical ceiling. Because the contact line is tapered, one 497 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 85.725 mm shaft typically takes a k5 seat with an H7 housing bore. Speed envelope and thermal behaviour: at 3,800 r/min thermal reference, the 85.725 mm bore shaft runs at a dn of 326k, and the 23.8 mm section dissipates heat through the cup-to-housing contact path; the 4,500 r/min mechanical ceiling reflects cage strength, and the 1450 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cup-side note for 492 A: the outer ring's rib profile and the 133.35 mm outside diameter are cup-specific within the 495-series tables, so substituting a different cup against the same 497 cone changes both the assembled 30.163 mm width and the axial free-play setting of the mounted pair.SKF 497 (SKF 497/492 A) is the 495-series tapered roller choice for a 85.725 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 133.35×30.163 mm envelope.Reading the designation: 497 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 495-series code identifies the dimensional series. The 85.725 mm bore, 133.35 mm OD and 30.163 mm width are the metric equivalents of the inch boundary dimensions.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "large process pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Mount the 85.725 mm bore 497 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 495-series inch series at 85.725 mm bore (133.35×30.163 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 497 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Do not mix brands or executions inside one 497 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 133.35 mm cup race release as noise within the first running hours.", "The 178/220 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 497 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 497/492 A designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in 497 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (495-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 497 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 497 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 497 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 497?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 30.163 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 497 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "497-492A-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 85.725×133.35×30.163 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "497-492A", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "497-492A" ], "locale_variants": {} }, { "sku": "665-653", "brand": "SKF", "manufacturer_designation": "SKF 665/653", "series": "655-series", "type": "tapered_roller", "d_mm": 85.725, "D_mm": 146.05, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 270, "static_load_kN": 320, "fatigue_load_limit_kN": 35.5, "max_rpm": 4300, "reference_speed_rpm": 3600, "limiting_speed_rpm": 4300, "weight_g": 2650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. With C 270 kN and C0 320 kN, the 665 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 4,300 r/min. Fit selection follows the rotating ring — interference on a rotating cone — and two 665 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Journal and housing interface: the 85.725 mm bore takes a k5 shaft seat (upper deviation ~0.171 mm for this diameter range) and the 146.05 mm outside diameter pairs with an H7 housing bore tolerance band of 146.05.000/146.070 mm; the 41.275 mm width defines the shoulder depth, and the 2650 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Housing and abutment design flows from the cup: in 665 the 653 cup fixes the 146.05 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the 665 cone determines the 85.725 mm shaft interface; the 41.275 mm width is the assembled pair value.665 is a single-row tapered roller bearing in the 655-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Reading the designation: 665 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 655-series code identifies the dimensional series. The 85.725 mm bore, 146.05 mm OD and 41.275 mm width are the metric equivalents of the inch boundary dimensions.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "construction machinery drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Mount the 85.725 mm bore 665 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 655-series inch series at 85.725 mm bore (146.05×41.275 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 665 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 665 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Catalogue reference speed and limiting speed are different limits: the 3,600 r/min reference is a thermal criterion under load, while the 4,300 r/min limiting value is the mechanical ceiling — observe both.", "The 270/320 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 665 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 665/653 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in 665 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (655-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 665 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 665 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 665 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 665?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 41.275 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 665 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "665-653-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 85.725×146.05×41.275 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "665-653", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "665-653" ], "locale_variants": {} }, { "sku": "593-592A", "brand": "SKF", "manufacturer_designation": "SKF 593/592 A", "series": "593-series", "type": "tapered_roller", "d_mm": 88.9, "D_mm": 152.4, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 237, "static_load_kN": 305, "fatigue_load_limit_kN": 33.5, "max_rpm": 4300, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4300, "weight_g": 2800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF inch-series tables 593 sits at 88.9 mm bore (3.5 in) with a 152.4 mm cup OD and 39.688 mm total width — dimensions that trace back to the original Timken boundary plan for the 593-series family. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. The 31.8 mm radial section height ((152.4−88.9)/2) and 2800 g catalogue mass frame a 88.9 mm bore bearing rated at 237 kN C — roughly 2.67 kN of dynamic capacity per millimetre of bore before application factors. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 593 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Speed envelope and thermal behaviour: at 3,400 r/min thermal reference, the 88.9 mm bore shaft runs at a dn of 302k, and the 31.8 mm section dissipates heat through the cup-to-housing contact path; the 4,300 r/min mechanical ceiling reflects cage strength, and the 2800 g spinning cone contributes gyroscopic moment under rapid speed reversal. Inch tapered bearings are matched sets, not mix-and-match components: 593 pairs the 593 cone with the 592 A cup under the 593-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.For a 88.9 mm shaft carrying combined load, SKF lists 593 under catalogue execution SKF 593/592 A: one open single-row tapered roller bearing in the inch 593-series.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "crane sheave and hoist gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Mount the 88.9 mm bore 593 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 593-series inch series at 88.9 mm bore (152.4×39.688 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 593 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 593 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Shaft and housing fillets must clear the bearing chamfer so the 39.688 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 237/305 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 593 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 593/592 A designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 593 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 593-series code marks the dimensional series. The metric dimensions 88.9×152.4×39.688 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 593 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (593-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 593 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 593 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 593 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 593?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 39.688 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "593-592A-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 88.9×152.4×39.688 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "593-592A", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "593-592A" ], "locale_variants": {} }, { "sku": "HM518445-410", "brand": "SKF", "manufacturer_designation": "SKF HM 518445/410", "series": "HM518400-series", "type": "tapered_roller", "d_mm": 88.9, "D_mm": 152.4, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 300, "static_load_kN": 355, "fatigue_load_limit_kN": 39, "max_rpm": 4000, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4000, "weight_g": 2850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Journal and housing interface: the 88.9 mm bore takes a k5 shaft seat (upper deviation ~0.178 mm for this diameter range) and the 152.4 mm outside diameter pairs with an H7 housing bore tolerance band of 152.4.000/152.420 mm; the 39.688 mm width defines the shoulder depth, and the 2850 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Cup-side note for 410: the outer ring's rib profile and the 152.4 mm outside diameter are cup-specific within the HM518400-series tables, so substituting a different cup against the same HM 518445 cone changes both the assembled 39.688 mm width and the axial free-play setting of the mounted pair.Ordering number SKF HM 518445/410 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 88.9 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.In SKF inch-series tables HM518445 sits at 88.9 mm bore (3.5 in) with a 152.4 mm cup OD and 39.688 mm total width — dimensions that trace back to the original Timken boundary plan for the HM518400-series family. In SKF suffix language a bare HM518445 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 1.18 (static 355 kN against dynamic 300 kN), typical of a tapered roller sized for axial capacity, and the 39 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. A single HM518445 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "Mount the 88.9 mm bore HM518445 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The HM518400-series inch series at 88.9 mm bore (152.4×39.688 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HM518445 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HM518445 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The 2850 g mass and 39.688 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of HM518445.", "The 300/355 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM518445 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 518445/410 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit HM518445?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 39.688 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HM518445 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM518445?", "a": "The SKF HM 518445/410 is a single-row tapered roller bearing with 88.9 mm bore, 152.4 mm outer diameter and 39.688 mm width (3.5 × 6 × 1.563 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 300 kN, C0 355 kN, fatigue load limit Pu 39 kN, reference speed 3,400 r/min, limiting speed 4,000 r/min, mass about 2850 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM518445 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM518400-series code marks the dimensional series. The metric dimensions 88.9×152.4×39.688 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM518445 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM518400-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "HM518445-410", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM518445-410" ], "locale_variants": {} }, { "sku": "6580-6535", "brand": "SKF", "manufacturer_designation": "SKF 6580/6535", "series": "6500-series", "type": "tapered_roller", "d_mm": 88.9, "D_mm": 161.925, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 404, "static_load_kN": 510, "fatigue_load_limit_kN": 56, "max_rpm": 4000, "reference_speed_rpm": 3200, "limiting_speed_rpm": 4000, "weight_g": 4800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " For a 88.9 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 6580 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Load system: the 404 kN basic dynamic rating C and 510 kN static rating C0 give a C0/C balance of 1.26, and dividing C by the 88.9 mm bore yields 4.54 kN per millimetre of journal — a density metric that compares across families; the 56 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 88.9 mm shaft carrying variable duty. Inch tapered bearings are matched sets, not mix-and-match components: 6580 pairs the 6580 cone with the 6535 cup under the 6500-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.SKF 6580 (SKF 6580/6535) is the 6500-series tapered roller choice for a 88.9 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 161.925×53.975 mm envelope.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (6500-series) ties the pair to a specific boundary plan. Dimensions 88.9×161.925×53.975 mm are the converted metric envelope. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Speed planning uses two different ceilings: 3,200 r/min thermal reference and 4,000 r/min mechanical limiting speed.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "construction machinery drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "Mount the 88.9 mm bore 6580 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 6500-series inch series at 88.9 mm bore (161.925×53.975 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 6580 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "A single 6580 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 161.925 mm cup race release as noise within the first running hours.", "The 404/510 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 6580 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 6580/6535 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 6580 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 6580 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 6580?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 53.975 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 6580 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 6580?", "a": "The SKF 6580/6535 is a single-row tapered roller bearing with 88.9 mm bore, 161.925 mm outer diameter and 53.975 mm width (3.5 × 6.375 × 2.125 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 404 kN, C0 510 kN, fatigue load limit Pu 56 kN, reference speed 3,200 r/min, limiting speed 4,000 r/min, mass about 4800 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 6580 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 6500-series code marks the dimensional series. The metric dimensions 88.9×161.925×53.975 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "6580-6535-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 88.9×161.925×53.975 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "6580-6535", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "6580-6535" ], "locale_variants": {} }, { "sku": "HM218248-210", "brand": "SKF", "manufacturer_designation": "SKF HM 218248/210", "series": "HM218200-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 147, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 280, "static_load_kN": 355, "fatigue_load_limit_kN": 39, "max_rpm": 4300, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4300, "weight_g": 2550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " For a 90 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two HM218248 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Speed envelope and thermal behaviour: at 3,400 r/min thermal reference, the 90 mm bore shaft runs at a dn of 306k, and the 28.5 mm section dissipates heat through the cup-to-housing contact path; the 4,300 r/min mechanical ceiling reflects cage strength, and the 2550 g spinning cone contributes gyroscopic moment under rapid speed reversal. The cup reference 210 is structural, not a suffix: it identifies the outer ring that, combined with the HM 218248 cone, produces the 90/147/40 mm envelope catalogue-listed as HM218248. Quote the cup number in full when ordering — the HM218200-series tables contain other cups that fit the same cone but change the bearing.Ordering number SKF HM 218248/210 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 90 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.The HM218200-series series assigns 90 mm bore, 147 mm OD and 40 mm width to HM218248; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. The 39 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.27 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "rolling-mill auxiliary drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Mount the 90 mm bore HM218248 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The HM218200-series inch series at 90 mm bore (147×40 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one HM218248 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common HM218248 mounting error.", "Catalogue reference speed and limiting speed are different limits: the 3,400 r/min reference is a thermal criterion under load, while the 4,300 r/min limiting value is the mechanical ceiling — observe both.", "The 280/355 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM218248 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 218248/210 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does HM218248 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM218248 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HM218248?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 40 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HM218248 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM218248?", "a": "The SKF HM 218248/210 is a single-row tapered roller bearing with 90 mm bore, 147 mm outer diameter and 40 mm width (3.543 × 5.787 × 1.575 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 280 kN, C0 355 kN, fatigue load limit Pu 39 kN, reference speed 3,400 r/min, limiting speed 4,300 r/min, mass about 2550 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM218248 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM218200-series code marks the dimensional series. The metric dimensions 90×147×40 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "HM218248-HM218210", "equiv_brand": "NTN", "level": "partial", "note": "Same 90×147×40 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "HM218248-210", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM218248-210" ], "locale_variants": {} }, { "sku": "6581X-6535", "brand": "SKF", "manufacturer_designation": "SKF 6581 X/6535", "series": "6500-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 161.925, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 404, "static_load_kN": 510, "fatigue_load_limit_kN": 56, "max_rpm": 4000, "reference_speed_rpm": 3200, "limiting_speed_rpm": 4000, "weight_g": 4750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 90 mm shaft carrying combined load, SKF lists 6581X under catalogue execution SKF 6581 X/6535: one open single-row tapered roller bearing in the inch 6500-series.Reading the designation: 6581X follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 6500-series code identifies the dimensional series. The 90 mm bore, 161.925 mm OD and 53.975 mm width are the metric equivalents of the inch boundary dimensions. In SKF suffix language a bare 6581X is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 36.0 mm radial section height ((161.925−90)/2) and 4750 g catalogue mass frame a 90 mm bore bearing rated at 404 kN C — roughly 4.49 kN of dynamic capacity per millimetre of bore before application factors. Because the contact line is tapered, one 6581X reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 90 mm shaft typically takes a k5 seat with an H7 housing bore. Dimensional interchange map: within the 65800 series at 90 mm bore, the 161.925 mm OD and 53.975 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 36.0 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 4750 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Two catalogue entries share the 6581 X cone but use different cups; this one, 6581X, takes the 6535 cup and is ground for the resulting 161.925 mm OD / 53.975 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "rolling-mill auxiliary drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Mount the 90 mm bore 6581X by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 6500-series inch series at 90 mm bore (161.925×53.975 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 6581X rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Setting is a design value, not an assembly feel: excessive preload in the 6581X pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Catalogue reference speed and limiting speed are different limits: the 3,200 r/min reference is a thermal criterion under load, while the 4,000 r/min limiting value is the mechanical ceiling — observe both.", "The 404/510 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 6581X (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 6581 X/6535 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 6581X?", "a": "The SKF 6581 X/6535 is a single-row tapered roller bearing with 90 mm bore, 161.925 mm outer diameter and 53.975 mm width (3.543 × 6.375 × 2.125 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 404 kN, C0 510 kN, fatigue load limit Pu 56 kN, reference speed 3,200 r/min, limiting speed 4,000 r/min, mass about 4750 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 6581X inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 6500-series code marks the dimensional series. The metric dimensions 90×161.925×53.975 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 6581X mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (6500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 6581X take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 6581X compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 6581X position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "6581X-6535", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "6581X-6535" ], "locale_variants": {} }, { "sku": "47890-47820", "brand": "SKF", "manufacturer_designation": "SKF 47890/47820", "series": "47800-series", "type": "tapered_roller", "d_mm": 92.075, "D_mm": 146.05, "B_mm": 33.338, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 209, "static_load_kN": 280, "fatigue_load_limit_kN": 31.5, "max_rpm": 4300, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4300, "weight_g": 2100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Dimensional interchange map: within the 47800 series at 92.075 mm bore, the 146.05 mm OD and 33.338 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 27.0 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 2100 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Inch tapered bearings are matched sets, not mix-and-match components: 47890 pairs the 47890 cone with the 47820 cup under the 47800-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.SKF 47890/47820 belongs to the SKF single-row tapered roller range — the 92.075 mm bore entry in the inch 47800-series, dimensioned 146.05 mm OD and 33.338 mm wide.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (47800-series) ties the pair to a specific boundary plan. Dimensions 92.075×146.05×33.338 mm are the converted metric envelope. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 2100 g for the 92.075×146.05×33.338 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Fit selection follows the rotating ring — interference on a rotating cone — and two 47890 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Mount the 92.075 mm bore 47890 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 47800-series inch series at 92.075 mm bore (146.05×33.338 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 47890 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "A single 47890 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Catalogue reference speed and limiting speed are different limits: the 3,400 r/min reference is a thermal criterion under load, while the 4,300 r/min limiting value is the mechanical ceiling — observe both.", "The 209/280 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 47890 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 47890/47820 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 47890?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 33.338 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 47890 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 47890?", "a": "The SKF 47890/47820 is a single-row tapered roller bearing with 92.075 mm bore, 146.05 mm outer diameter and 33.338 mm width (3.625 × 5.75 × 1.313 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 209 kN, C0 280 kN, fatigue load limit Pu 31.5 kN, reference speed 3,400 r/min, limiting speed 4,300 r/min, mass about 2100 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 47890 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 47800-series code marks the dimensional series. The metric dimensions 92.075×146.05×33.338 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 47890 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (47800-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "47890-47820-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 92.075×146.05×33.338 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "47890-47820", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "47890-47820" ], "locale_variants": {} }, { "sku": "598-592A", "brand": "SKF", "manufacturer_designation": "SKF 598/592 A", "series": "595-series", "type": "tapered_roller", "d_mm": 92.075, "D_mm": 152.4, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 237, "static_load_kN": 305, "fatigue_load_limit_kN": 33.5, "max_rpm": 4300, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4300, "weight_g": 2700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Fit selection follows the rotating ring — interference on a rotating cone — and two 598 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Speed envelope and thermal behaviour: at 3,400 r/min thermal reference, the 92.075 mm bore shaft runs at a dn of 313k, and the 30.2 mm section dissipates heat through the cup-to-housing contact path; the 4,300 r/min mechanical ceiling reflects cage strength, and the 2700 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cone-and-cup identity in 598: the leading 598 reference identifies the inner ring, rollers and cage; the trailing 592 A reference identifies the outer ring. The 595-series series lists alternative cups for the same cone, each producing a different 152.4 mm OD or 39.688 mm width — hence a different SKU even though the bore stays at 92.075 mm.SKF 598 (SKF 598/592 A) is the 595-series tapered roller choice for a 92.075 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 152.4×39.688 mm envelope.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (595-series) ties the pair to a specific boundary plan. Dimensions 92.075×152.4×39.688 mm are the converted metric envelope. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 2700 g for the 92.075×152.4×39.688 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "large process pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Mount the 92.075 mm bore 598 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 595-series inch series at 92.075 mm bore (152.4×39.688 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 598 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "At the 237 kN rating of 598, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 4,300 r/min speed end and heavier preload only where moment stiffness dominates.", "The 598 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 237/305 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 598 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 598/592 A designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 598 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 598 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 598?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 39.688 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 598 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 598?", "a": "The SKF 598/592 A is a single-row tapered roller bearing with 92.075 mm bore, 152.4 mm outer diameter and 39.688 mm width (3.625 × 6 × 1.563 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 237 kN, C0 305 kN, fatigue load limit Pu 33.5 kN, reference speed 3,400 r/min, limiting speed 4,300 r/min, mass about 2700 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 598 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 595-series code marks the dimensional series. The metric dimensions 92.075×152.4×39.688 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "598-592A", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "598-592A" ], "locale_variants": {} }, { "sku": "47896-47820", "brand": "SKF", "manufacturer_designation": "SKF 47896/47820", "series": "47800-series", "type": "tapered_roller", "d_mm": 95.25, "D_mm": 146.05, "B_mm": 33.338, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 209, "static_load_kN": 280, "fatigue_load_limit_kN": 31.5, "max_rpm": 4300, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4300, "weight_g": 1950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Reading the designation: 47896 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 47800-series code identifies the dimensional series. The 95.25 mm bore, 146.05 mm OD and 33.338 mm width are the metric equivalents of the inch boundary dimensions. In SKF suffix language a bare 47896 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Speed planning uses two different ceilings: 3,400 r/min thermal reference and 4,300 r/min mechanical limiting speed. For a 95.25 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 47896 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Journal and housing interface: the 95.25 mm bore takes a k5 shaft seat (upper deviation ~0.191 mm for this diameter range) and the 146.05 mm outside diameter pairs with an H7 housing bore tolerance band of 146.05.000/146.070 mm; the 33.338 mm width defines the shoulder depth, and the 1950 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Within the 47800-series tables, 47896 appears in several rows because SKF lists multiple cup options for the same cone. 47896 is the 47820 variant, with 146.05 mm OD and 33.338 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.SKF 47896 (SKF 47896/47820) is the 47800-series tapered roller choice for a 95.25 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 146.05×33.338 mm envelope.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "rolling-mill auxiliary drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Mount the 95.25 mm bore 47896 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 47800-series inch series at 95.25 mm bore (146.05×33.338 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 47896 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "A single 47896 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 209/280 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 47896 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 47896/47820 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 47896 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 47800-series code marks the dimensional series. The metric dimensions 95.25×146.05×33.338 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 47896 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (47800-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 47896 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 47896 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 47896 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 47896?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 33.338 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "47896-47820-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 95.25×146.05×33.338 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "47896-47820", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "47896-47820" ], "locale_variants": {} }, { "sku": "594A-592A", "brand": "SKF", "manufacturer_designation": "SKF 594 A/592 A", "series": "595-series", "type": "tapered_roller", "d_mm": 95.25, "D_mm": 152.4, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 237, "static_load_kN": 305, "fatigue_load_limit_kN": 33.5, "max_rpm": 4300, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4300, "weight_g": 2550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Fit selection follows the rotating ring — interference on a rotating cone — and two 594A units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Journal and housing interface: the 95.25 mm bore takes a k5 shaft seat (upper deviation ~0.191 mm for this diameter range) and the 152.4 mm outside diameter pairs with an H7 housing bore tolerance band of 152.4.000/152.420 mm; the 39.688 mm width defines the shoulder depth, and the 2550 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Why the cup reference matters here: in the 595-series tables the 594 A cone appears against several cup options. 594A is the pairing with 592 A, and that choice — not the cone — fixes the 152.4 mm OD, the raceway track position and the 39.688 mm assembled width.The SKF 594 A/592 A is a 95.25×152.4×39.688 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.The 595-series series assigns 95.25 mm bore, 152.4 mm OD and 39.688 mm width to 594A; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Catalogue mass 2550 g for the 95.25×152.4×39.688 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "large process pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "Mount the 95.25 mm bore 594A by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 595-series inch series at 95.25 mm bore (152.4×39.688 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one 594A pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Setting is a design value, not an assembly feel: excessive preload in the 594A pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 152.4 mm cup race release as noise within the first running hours.", "The 237/305 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 594A (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 594 A/592 A designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 594A compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 594A position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 594A?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 39.688 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 594A interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 594A?", "a": "The SKF 594 A/592 A is a single-row tapered roller bearing with 95.25 mm bore, 152.4 mm outer diameter and 39.688 mm width (3.75 × 6 × 1.563 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 237 kN, C0 305 kN, fatigue load limit Pu 33.5 kN, reference speed 3,400 r/min, limiting speed 4,300 r/min, mass about 2550 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 594A inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 595-series code marks the dimensional series. The metric dimensions 95.25×152.4×39.688 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "594A-592XE", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "594A-592A", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "594A-592A" ], "locale_variants": {} }, { "sku": "594-592A", "brand": "SKF", "manufacturer_designation": "SKF 594/592 A", "series": "595-series", "type": "tapered_roller", "d_mm": 95.25, "D_mm": 152.4, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 237, "static_load_kN": 305, "fatigue_load_limit_kN": 33.5, "max_rpm": 4300, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4300, "weight_g": 2550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Two catalogue entries share the 594 cone but use different cups; this one, 594, takes the 592 A cup and is ground for the resulting 152.4 mm OD / 39.688 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.SKF 594/592 A belongs to the SKF single-row tapered roller range — the 95.25 mm bore entry in the inch 595-series, dimensioned 152.4 mm OD and 39.688 mm wide.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (595-series) ties the pair to a specific boundary plan. Dimensions 95.25×152.4×39.688 mm are the converted metric envelope. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Selection arithmetic: the C0/C ratio is about 1.29 (static 305 kN against dynamic 237 kN), typical of a tapered roller sized for axial capacity, and the 33.5 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Fit selection follows the rotating ring — interference on a rotating cone — and two 594 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Speed envelope and thermal behaviour: at 3,400 r/min thermal reference, the 95.25 mm bore shaft runs at a dn of 324k, and the 28.6 mm section dissipates heat through the cup-to-housing contact path; the 4,300 r/min mechanical ceiling reflects cage strength, and the 2550 g spinning cone contributes gyroscopic moment under rapid speed reversal.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "marine deck machinery shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Mount the 95.25 mm bore 594 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 595-series inch series at 95.25 mm bore (152.4×39.688 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one 594 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "A single 594 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 152.4 mm cup race release as noise within the first running hours.", "The 237/305 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 594 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 594/592 A designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 594 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 594?", "a": "The SKF 594/592 A is a single-row tapered roller bearing with 95.25 mm bore, 152.4 mm outer diameter and 39.688 mm width (3.75 × 6 × 1.563 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 237 kN, C0 305 kN, fatigue load limit Pu 33.5 kN, reference speed 3,400 r/min, limiting speed 4,300 r/min, mass about 2550 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 594 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 595-series code marks the dimensional series. The metric dimensions 95.25×152.4×39.688 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 594 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (595-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 594 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "594-592A-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 95.25×152.4×39.688 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "594-592A", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "594-592A" ], "locale_variants": {} }, { "sku": "683-672", "brand": "SKF", "manufacturer_designation": "SKF 683/672", "series": "675-series", "type": "tapered_roller", "d_mm": 95.25, "D_mm": 168.275, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 288, "static_load_kN": 365, "fatigue_load_limit_kN": 39, "max_rpm": 3800, "reference_speed_rpm": 3000, "limiting_speed_rpm": 3800, "weight_g": 3750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Journal and housing interface: the 95.25 mm bore takes a k5 shaft seat (upper deviation ~0.191 mm for this diameter range) and the 168.275 mm outside diameter pairs with an H7 housing bore tolerance band of 168.275.000/168.295 mm; the 41.275 mm width defines the shoulder depth, and the 3750 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 683 the 683 cone contributes the 95.25 mm bore and roller set, the 672 cup contributes the 168.275 mm OD raceway, and the assembled 41.275 mm width is the catalogue value.683 is a single-row tapered roller bearing in the 675-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Digit by digit, 683 reads as cone reference / cup reference in the 675-series inch series; the 95.25 mm bore, 168.275 mm OD and 41.275 mm width are the metric equivalents of the original inch boundary values. In SKF suffix language a bare 683 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 1.27 (static 365 kN against dynamic 288 kN), typical of a tapered roller sized for axial capacity, and the 39 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 683 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Mount the 95.25 mm bore 683 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 675-series inch series at 95.25 mm bore (168.275×41.275 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 683 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Do not mix brands or executions inside one 683 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Open 683 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 288/365 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 683 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 683/672 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 683?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 41.275 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 683 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 683?", "a": "The SKF 683/672 is a single-row tapered roller bearing with 95.25 mm bore, 168.275 mm outer diameter and 41.275 mm width (3.75 × 6.625 × 1.625 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 288 kN, C0 365 kN, fatigue load limit Pu 39 kN, reference speed 3,000 r/min, limiting speed 3,800 r/min, mass about 3750 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 683 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 675-series code marks the dimensional series. The metric dimensions 95.25×168.275×41.275 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 683 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (675-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "683-672-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 95.25×168.275×41.275 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "683-672", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "683-672" ], "locale_variants": {} }, { "sku": "90381-90744", "brand": "SKF", "manufacturer_designation": "SKF 90381/90744", "series": "90300-series", "type": "tapered_roller", "d_mm": 96.838, "D_mm": 188.912, "B_mm": 50.8, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 348, "static_load_kN": 375, "fatigue_load_limit_kN": 41.5, "max_rpm": 3400, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3400, "weight_g": 5750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Reading the designation: 90381 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 90300-series code identifies the dimensional series. The 96.838 mm bore, 188.912 mm OD and 50.8 mm width are the metric equivalents of the inch boundary dimensions. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Selection arithmetic: the C0/C ratio is about 1.08 (static 375 kN against dynamic 348 kN), typical of a tapered roller sized for axial capacity, and the 41.5 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. For a 96.838 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 90381 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Operating context for the 96.838 mm bore: a shaft of this diameter in the large-bore band typically runs between 77470 and 116206 r/min in real machinery, and the 188.912 mm outside diameter places the housing shoulder at 197 mm outer abutment; the 50.8 mm width and 5750 g mass together set the shaft critical speed and the housing resonance check for this 90300-series envelope. Cone versus cup responsibility in 90381: the 90381 cone carries the 96.838 mm bore, rollers and pressed-steel cage; the 90744 cup carries the 188.912 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.In SKF catalogue PUB BU/P1 17000, 90381 appears as SKF 90381/90744: an open, single-row tapered roller bearing in the 90300-series, supplied with a pressed-steel cage as standard.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "large process pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "Mount the 96.838 mm bore 90381 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 90300-series inch series at 96.838 mm bore (188.912×50.8 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 90381 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 90381 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 188.912 mm cup race release as noise within the first running hours.", "The 348/375 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 90381 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 90381/90744 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 90381 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 90300-series code marks the dimensional series. The metric dimensions 96.838×188.912×50.8 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 90381 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (90300-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 90381 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 90381 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 90381 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 90381?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 50.8 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "90381-90744-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 96.838×188.912×50.8 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "90381-90744", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "90381-90744" ], "locale_variants": {} }, { "sku": "HH224334-310", "brand": "SKF", "manufacturer_designation": "SKF HH 224334/310", "series": "HH224300-series", "type": "tapered_roller", "d_mm": 99.975, "D_mm": 212.725, "B_mm": 66.675, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 619, "static_load_kN": 830, "fatigue_load_limit_kN": 88, "max_rpm": 3000, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3000, "weight_g": 11500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The cup reference 310 is structural, not a suffix: it identifies the outer ring that, combined with the HH 224334 cone, produces the 99.975/212.725/66.675 mm envelope catalogue-listed as HH224334. Quote the cup number in full when ordering — the HH224300-series tables contain other cups that fit the same cone but change the bearing.In SKF catalogue PUB BU/P1 17000, HH224334 appears as SKF HH 224334/310: an open, single-row tapered roller bearing in the HH224300-series, supplied with a pressed-steel cage as standard.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (HH224300-series) ties the pair to a specific boundary plan. Dimensions 99.975×212.725×66.675 mm are the converted metric envelope. In SKF suffix language a bare HH224334 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 88 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.34 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of HH224334 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Material and manufacturing detail: the 11500 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the HH200 ISO envelope, with the pressed-steel cage contributing roughly 345 g of the total; the 99.975 mm bore is ground to IT5 roundness and the 212.725 mm OD to IT5 cylindricity, and the 66.675 mm width tolerance keeps the pair-setting scatter within the ISO preload class.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "paper-machine and printing rolls" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Mount the 99.975 mm bore HH224334 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The HH224300-series inch series at 99.975 mm bore (212.725×66.675 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one HH224334 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common HH224334 mounting error.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 619/830 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HH224334 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HH 224334/310 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is HH224334 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HH224334?", "a": "The SKF HH 224334/310 is a single-row tapered roller bearing with 99.975 mm bore, 212.725 mm outer diameter and 66.675 mm width (3.936 × 8.375 × 2.625 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 619 kN, C0 830 kN, fatigue load limit Pu 88 kN, reference speed 2,200 r/min, limiting speed 3,000 r/min, mass about 11500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HH224334 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HH224300-series code marks the dimensional series. The metric dimensions 99.975×212.725×66.675 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HH224334 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HH224300-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single HH224334 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "HH224334-HH224310", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "HH224334-310", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HH224334-310" ], "locale_variants": {} }, { "sku": "HM220149A-110", "brand": "SKF", "manufacturer_designation": "SKF HM 220149 A/110", "series": "HM220100-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 157, "B_mm": 42, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 303, "static_load_kN": 400, "fatigue_load_limit_kN": 42.5, "max_rpm": 4000, "reference_speed_rpm": 3200, "limiting_speed_rpm": 4000, "weight_g": 2900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Fit selection follows the rotating ring — interference on a rotating cone — and two HM220149A units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Cross-section geometry: the 28.5 mm half-section ((157−100)/2) of this HM200-series unit places the roller large-end pitch diameter at roughly 128 mm, and the 42 mm axial width is split between cone (23 mm) and cup rib (19 mm) — a geometry that sets the contact angle and, with the 2900 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Within the HM220100-series tables, HM 220149 A appears in several rows because SKF lists multiple cup options for the same cone. HM220149A is the 110 variant, with 157 mm OD and 42 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.In SKF catalogue PUB BU/P1 17000, HM220149A appears as SKF HM 220149 A/110: an open, single-row tapered roller bearing in the HM220100-series, supplied with a pressed-steel cage as standard.Digit by digit, HM220149A reads as cone reference / cup reference in the HM220100-series inch series; the 100 mm bore, 157 mm OD and 42 mm width are the metric equivalents of the original inch boundary values. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 2900 g for the 100×157×42 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "large process pump and compressor shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Mount the 100 mm bore HM220149A by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The HM220100-series inch series at 100 mm bore (157×42 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 303 kN rating of HM220149A, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 4,000 r/min speed end and heavier preload only where moment stiffness dominates.", "Do not mix brands or executions inside one HM220149A pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Catalogue reference speed and limiting speed are different limits: the 3,200 r/min reference is a thermal criterion under load, while the 4,000 r/min limiting value is the mechanical ceiling — observe both.", "The 303/400 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM220149A (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 220149 A/110 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does HM220149A compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM220149A position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HM220149A?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 42 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HM220149A interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM220149A?", "a": "The SKF HM 220149 A/110 is a single-row tapered roller bearing with 100 mm bore, 157 mm outer diameter and 42 mm width (3.937 × 6.181 × 1.654 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 303 kN, C0 400 kN, fatigue load limit Pu 42.5 kN, reference speed 3,200 r/min, limiting speed 4,000 r/min, mass about 2900 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM220149A inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM220100-series code marks the dimensional series. The metric dimensions 100×157×42 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "HM220149A-110", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM220149A-110" ], "locale_variants": {} }, { "sku": "HM220149-110", "brand": "SKF", "manufacturer_designation": "SKF HM 220149/110", "series": "HM220100-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 157, "B_mm": 42, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 303, "static_load_kN": 400, "fatigue_load_limit_kN": 42.5, "max_rpm": 4000, "reference_speed_rpm": 3200, "limiting_speed_rpm": 4000, "weight_g": 2900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " For a 100 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two HM220149 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Load system: the 303 kN basic dynamic rating C and 400 kN static rating C0 give a C0/C balance of 1.32, and dividing C by the 100 mm bore yields 3.03 kN per millimetre of journal — a density metric that compares across families; the 42.5 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 100 mm shaft carrying variable duty. From a specification standpoint the 110 cup is the controlling half of HM220149 for housing design — it sets the 157 mm OD and the outer abutment diameter — while the HM 220149 cone controls shaft fit at the 100 mm bore; the 42 mm width is the result of the two together.Ordering number SKF HM 220149/110 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 100 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.In SKF inch-series tables HM220149 sits at 100 mm bore (3.937 in) with a 157 mm cup OD and 42 mm total width — dimensions that trace back to the original Timken boundary plan for the HM220100-series family. In SKF suffix language a bare HM220149 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. With C 303 kN and C0 400 kN, the HM220149 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 4,000 r/min.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Mount the 100 mm bore HM220149 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The HM220100-series inch series at 100 mm bore (157×42 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the HM220149 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common HM220149 mounting error.", "Catalogue reference speed and limiting speed are different limits: the 3,200 r/min reference is a thermal criterion under load, while the 4,000 r/min limiting value is the mechanical ceiling — observe both.", "The 303/400 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM220149 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 220149/110 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does HM220149 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM220149 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HM220149?", "a": "For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 42 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HM220149 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM220149?", "a": "The SKF HM 220149/110 is a single-row tapered roller bearing with 100 mm bore, 157 mm outer diameter and 42 mm width (3.937 × 6.181 × 1.654 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 303 kN, C0 400 kN, fatigue load limit Pu 42.5 kN, reference speed 3,200 r/min, limiting speed 4,000 r/min, mass about 2900 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM220149 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM220100-series code marks the dimensional series. The metric dimensions 100×157×42 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "HM220149-110", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM220149-110" ], "locale_variants": {} }, { "sku": "687-672", "brand": "SKF", "manufacturer_designation": "SKF 687/672", "series": "675-series", "type": "tapered_roller", "d_mm": 101.6, "D_mm": 168.275, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 288, "static_load_kN": 365, "fatigue_load_limit_kN": 39, "max_rpm": 3800, "reference_speed_rpm": 3000, "limiting_speed_rpm": 3800, "weight_g": 3450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Two catalogue entries share the 687 cone but use different cups; this one, 687, takes the 672 cup and is ground for the resulting 168.275 mm OD / 41.275 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.SKF 687 (SKF 687/672) is the 675-series tapered roller choice for a 101.6 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 168.275×41.275 mm envelope.Reading the designation: 687 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 675-series code identifies the dimensional series. The 101.6 mm bore, 168.275 mm OD and 41.275 mm width are the metric equivalents of the inch boundary dimensions. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. With C 288 kN and C0 365 kN, the 687 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 3,800 r/min. A single 687 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Cross-section geometry: the 33.3 mm half-section ((168.275−101.6)/2) of this 68700-series unit places the roller large-end pitch diameter at roughly 134 mm, and the 41.275 mm axial width is split between cone (23 mm) and cup rib (19 mm) — a geometry that sets the contact angle and, with the 3450 g rotating cone mass, the critical speed at which cage-roller imbalance begins.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "rolling-mill auxiliary drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Mount the 101.6 mm bore 687 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 675-series inch series at 101.6 mm bore (168.275×41.275 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 288 kN rating of 687, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 3,800 r/min speed end and heavier preload only where moment stiffness dominates.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 687 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The 687 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 288/365 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 687 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 687/672 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 687 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 687?", "a": "The SKF 687/672 is a single-row tapered roller bearing with 101.6 mm bore, 168.275 mm outer diameter and 41.275 mm width (4 × 6.625 × 1.625 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 288 kN, C0 365 kN, fatigue load limit Pu 39 kN, reference speed 3,000 r/min, limiting speed 3,800 r/min, mass about 3450 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 687 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 675-series code marks the dimensional series. The metric dimensions 101.6×168.275×41.275 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 687 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (675-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 687 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "687-672-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 101.6×168.275×41.275 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "687-672", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "687-672" ], "locale_variants": {} }, { "sku": "HH221449-410", "brand": "SKF", "manufacturer_designation": "SKF HH 221449/410", "series": "HH221400-series", "type": "tapered_roller", "d_mm": 101.6, "D_mm": 190.5, "B_mm": 57.15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 537, "static_load_kN": 630, "fatigue_load_limit_kN": 68, "max_rpm": 3400, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3400, "weight_g": 7000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "HH221449 is a single-row tapered roller bearing in the HH221400-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.The HH221400-series series assigns 101.6 mm bore, 190.5 mm OD and 57.15 mm width to HH221449; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Catalogue mass 7000 g for the 101.6×190.5×57.15 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of HH221449 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Journal and housing interface: the 101.6 mm bore takes a m6 shaft seat (upper deviation ~0.203 mm for this diameter range) and the 190.5 mm outside diameter pairs with an H7 housing bore tolerance band of 190.5.000/190.520 mm; the 57.15 mm width defines the shoulder depth, and the 7000 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Why the cup reference matters here: in the HH221400-series tables the HH 221449 cone appears against several cup options. HH221449 is the pairing with 410, and that choice — not the cone — fixes the 190.5 mm OD, the raceway track position and the 57.15 mm assembled width.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "paper-machine and printing rolls" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Mount the 101.6 mm bore HH221449 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The HH221400-series inch series at 101.6 mm bore (190.5×57.15 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 537 kN rating of HH221449, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 3,400 r/min speed end and heavier preload only where moment stiffness dominates.", "Do not mix brands or executions inside one HH221449 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 190.5 mm cup race release as noise within the first running hours.", "The 537/630 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HH221449 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HH 221449/410 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of HH221449?", "a": "The SKF HH 221449/410 is a single-row tapered roller bearing with 101.6 mm bore, 190.5 mm outer diameter and 57.15 mm width (4 × 7.5 × 2.25 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 537 kN, C0 630 kN, fatigue load limit Pu 68 kN, reference speed 2,800 r/min, limiting speed 3,400 r/min, mass about 7000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HH221449 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HH221400-series code marks the dimensional series. The metric dimensions 101.6×190.5×57.15 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HH221449 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HH221400-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single HH221449 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HH221449 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HH221449 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "HH221449-HH221410", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "HH221449-410", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HH221449-410" ], "locale_variants": {} }, { "sku": "HH224335-310", "brand": "SKF", "manufacturer_designation": "SKF HH 224335/310", "series": "HH224300-series", "type": "tapered_roller", "d_mm": 101.6, "D_mm": 212.725, "B_mm": 66.675, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 619, "static_load_kN": 830, "fatigue_load_limit_kN": 88, "max_rpm": 3000, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3000, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Reading the designation: HH224335 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the HH224300-series code identifies the dimensional series. The 101.6 mm bore, 212.725 mm OD and 66.675 mm width are the metric equivalents of the inch boundary dimensions. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Catalogue mass 11000 g for the 101.6×212.725×66.675 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Fit selection follows the rotating ring — interference on a rotating cone — and two HH224335 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Material and manufacturing detail: the 11000 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the HH200 ISO envelope, with the pressed-steel cage contributing roughly 330 g of the total; the 101.6 mm bore is ground to IT5 roundness and the 212.725 mm OD to IT5 cylindricity, and the 66.675 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Housing and abutment design flows from the cup: in HH224335 the 310 cup fixes the 212.725 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the HH 224335 cone determines the 101.6 mm shaft interface; the 66.675 mm width is the assembled pair value.SKF HH224335 (SKF HH 224335/310) is the HH224300-series tapered roller choice for a 101.6 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 212.725×66.675 mm envelope.", "applications": [ "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives", "construction machinery drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "Mount the 101.6 mm bore HH224335 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The HH224300-series inch series at 101.6 mm bore (212.725×66.675 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HH224335 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "At the 619 kN rating of HH224335, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 3,000 r/min speed end and heavier preload only where moment stiffness dominates.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 212.725 mm cup race release as noise within the first running hours.", "The 619/830 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HH224335 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HH 224335/310 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the HH224335 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HH224300-series code marks the dimensional series. The metric dimensions 101.6×212.725×66.675 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HH224335 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HH224300-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single HH224335 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HH224335 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HH224335 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HH224335?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 66.675 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "HH224335-HH224310", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "HH224335-310", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HH224335-310" ], "locale_variants": {} }, { "sku": "37425-37625", "brand": "SKF", "manufacturer_designation": "SKF 37425/37625", "series": "37000-series", "type": "tapered_roller", "d_mm": 107.95, "D_mm": 158.75, "B_mm": 23.02, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 124, "static_load_kN": 163, "fatigue_load_limit_kN": 18.3, "max_rpm": 3800, "reference_speed_rpm": 3200, "limiting_speed_rpm": 3800, "weight_g": 1400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Speed planning uses two different ceilings: 3,200 r/min thermal reference and 3,800 r/min mechanical limiting speed. Fit selection follows the rotating ring — interference on a rotating cone — and two 37425 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Speed envelope and thermal behaviour: at 3,200 r/min thermal reference, the 107.95 mm bore shaft runs at a dn of 345k, and the 25.4 mm section dissipates heat through the cup-to-housing contact path; the 3,800 r/min mechanical ceiling reflects cage strength, and the 1400 g spinning cone contributes gyroscopic moment under rapid speed reversal. Why the cup reference matters here: in the 37000-series tables the 37425 cone appears against several cup options. 37425 is the pairing with 37625, and that choice — not the cone — fixes the 158.75 mm OD, the raceway track position and the 23.02 mm assembled width.For a 107.95 mm shaft carrying combined load, SKF lists 37425 under catalogue execution SKF 37425/37625: one open single-row tapered roller bearing in the inch 37000-series.On the SKF nameplate, 37425 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 37000-series marking the dimensional series. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number.", "applications": [ "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "paper-machine and printing rolls" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Mount the 107.95 mm bore 37425 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 320 series at 107.95 mm bore (158.75×23.02 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "A single 37425 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 37425 mounting error.", "The 37425 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 124/163 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 37425 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 37425/37625 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 37425 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 37425 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 37425 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 37425?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 23.02 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 37425 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 37425?", "a": "The SKF 37425/37625 is a single-row tapered roller bearing with 107.95 mm bore, 158.75 mm outer diameter and 23.02 mm width (4.25 × 6.25 × 0.906 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 124 kN, C0 163 kN, fatigue load limit Pu 18.3 kN, reference speed 3,200 r/min, limiting speed 3,800 r/min, mass about 1400 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "37425-37625-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "37425-37625", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "37425-37625" ], "locale_variants": {} }, { "sku": "56425-56650", "brand": "SKF", "manufacturer_designation": "SKF 56425/56650", "series": "56000-series", "type": "tapered_roller", "d_mm": 107.95, "D_mm": 165.1, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 256, "static_load_kN": 355, "fatigue_load_limit_kN": 37.5, "max_rpm": 3600, "reference_speed_rpm": 3000, "limiting_speed_rpm": 3600, "weight_g": 2700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in 56425 the 56425 cone contributes the 107.95 mm bore and roller set, the 56650 cup contributes the 165.1 mm OD raceway, and the assembled 36.512 mm width is the catalogue value.In SKF catalogue PUB BU/P1 17000, 56425 appears as SKF 56425/56650: an open, single-row tapered roller bearing in the 56000-series, supplied with a pressed-steel cage as standard.In SKF inch-series tables 56425 sits at 107.95 mm bore (4.25 in) with a 165.1 mm cup OD and 36.512 mm total width — dimensions that trace back to the original Timken boundary plan for the 56000-series family. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 37.5 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.39 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Because the contact line is tapered, one 56425 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 107.95 mm shaft typically takes a m6 seat with an H7 housing bore. Dimensional interchange map: within the 56400 series at 107.95 mm bore, the 165.1 mm OD and 36.512 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 28.6 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 2700 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "paper-machine and printing rolls" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Mount the 107.95 mm bore 56425 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 56000-series inch series at 107.95 mm bore (165.1×36.512 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 56425 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 56425 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 165.1 mm cup race release as noise within the first running hours.", "The 256/355 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 56425 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 56425/56650 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 56425 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 56425?", "a": "The SKF 56425/56650 is a single-row tapered roller bearing with 107.95 mm bore, 165.1 mm outer diameter and 36.512 mm width (4.25 × 6.5 × 1.437 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 256 kN, C0 355 kN, fatigue load limit Pu 37.5 kN, reference speed 3,000 r/min, limiting speed 3,600 r/min, mass about 2700 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 56425 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 56000-series code marks the dimensional series. The metric dimensions 107.95×165.1×36.512 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 56425 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (56000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 56425 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "56425-56650-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 107.95×165.1×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "56425-56650", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "56425-56650" ], "locale_variants": {} }, { "sku": "64432-64708", "brand": "SKF", "manufacturer_designation": "SKF 64432/64708", "series": "64000-series", "type": "tapered_roller", "d_mm": 110, "D_mm": 180, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 307, "static_load_kN": 415, "fatigue_load_limit_kN": 42.5, "max_rpm": 3400, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3400, "weight_g": 3950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Cone-and-cup identity in 64432: the leading 64432 reference identifies the inner ring, rollers and cage; the trailing 64708 reference identifies the outer ring. The 64000-series series lists alternative cups for the same cone, each producing a different 180 mm OD or 41.275 mm width — hence a different SKU even though the bore stays at 110 mm.64432 is a single-row tapered roller bearing in the 64000-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Numbering ties the bearing to its inch-series envelope: 64432 means a cone and cup matched pair in the 64000-series series — which is why the 110×180×41.275 mm outline swaps dimensionally with other inch-series bearings of the same code. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 307 kN and C0 415 kN, the 64432 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 3,400 r/min. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 64432 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Load system: the 307 kN basic dynamic rating C and 415 kN static rating C0 give a C0/C balance of 1.35, and dividing C by the 110 mm bore yields 2.79 kN per millimetre of journal — a density metric that compares across families; the 42.5 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 110 mm shaft carrying variable duty.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "rolling-mill auxiliary drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Mount the 110 mm bore 64432 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.", "The 64000-series inch series at 110 mm bore (180×41.275 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 64432 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "A single 64432 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 307/415 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 64432 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 64432/64708 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 64432 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 64432?", "a": "The SKF 64432/64708 is a single-row tapered roller bearing with 110 mm bore, 180 mm outer diameter and 41.275 mm width (4.331 × 7.087 × 1.625 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 307 kN, C0 415 kN, fatigue load limit Pu 42.5 kN, reference speed 2,800 r/min, limiting speed 3,400 r/min, mass about 3950 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 64432 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 64000-series code marks the dimensional series. The metric dimensions 110×180×41.275 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 64432 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (64000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 64432 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "64432-64708", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "64432-64708" ], "locale_variants": {} }, { "sku": "64450-64700", "brand": "SKF", "manufacturer_designation": "SKF 64450/64700", "series": "64000-series", "type": "tapered_roller", "d_mm": 114.3, "D_mm": 177.8, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 307, "static_load_kN": 415, "fatigue_load_limit_kN": 42.5, "max_rpm": 3400, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3400, "weight_g": 3600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The cup reference 64700 is structural, not a suffix: it identifies the outer ring that, combined with the 64450 cone, produces the 114.3/177.8/41.275 mm envelope catalogue-listed as 64450. Quote the cup number in full when ordering — the 64000-series tables contain other cups that fit the same cone but change the bearing.For a 114.3 mm shaft carrying combined load, SKF lists 64450 under catalogue execution SKF 64450/64700: one open single-row tapered roller bearing in the inch 64000-series.Digit by digit, 64450 reads as cone reference / cup reference in the 64000-series inch series; the 114.3 mm bore, 177.8 mm OD and 41.275 mm width are the metric equivalents of the original inch boundary values. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Speed planning uses two different ceilings: 2,800 r/min thermal reference and 3,400 r/min mechanical limiting speed. Mounting practice for 64450: the rotating cone takes the interference fit (m6 on a 114.3 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Speed envelope and thermal behaviour: at 2,800 r/min thermal reference, the 114.3 mm bore shaft runs at a dn of 320k, and the 31.8 mm section dissipates heat through the cup-to-housing contact path; the 3,400 r/min mechanical ceiling reflects cage strength, and the 3600 g spinning cone contributes gyroscopic moment under rapid speed reversal.", "applications": [ "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At 114.3 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 64000-series inch series at 114.3 mm bore (177.8×41.275 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 64450 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "A single 64450 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The 3600 g mass and 41.275 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 64450.", "The 307/415 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 64450 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 64450/64700 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 64450 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 64450?", "a": "The SKF 64450/64700 is a single-row tapered roller bearing with 114.3 mm bore, 177.8 mm outer diameter and 41.275 mm width (4.5 × 7 × 1.625 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 307 kN, C0 415 kN, fatigue load limit Pu 42.5 kN, reference speed 2,800 r/min, limiting speed 3,400 r/min, mass about 3600 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 64450 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 64000-series code marks the dimensional series. The metric dimensions 114.3×177.8×41.275 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 64450 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (64000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 64450 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "64450-64700-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 114.3×177.8×41.275 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "64450-64700", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "64450-64700" ], "locale_variants": {} }, { "sku": "68450-68712", "brand": "SKF", "manufacturer_designation": "SKF 68450/68712", "series": "68000-series", "type": "tapered_roller", "d_mm": 114.3, "D_mm": 180.975, "B_mm": 34.925, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 227, "static_load_kN": 280, "fatigue_load_limit_kN": 30, "max_rpm": 3400, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3400, "weight_g": 2950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Reading the designation: 68450 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 68000-series code identifies the dimensional series. The 114.3 mm bore, 180.975 mm OD and 34.925 mm width are the metric equivalents of the inch boundary dimensions. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 227 kN and C0 280 kN, the 68450 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 3,400 r/min. Because the contact line is tapered, one 68450 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 114.3 mm shaft typically takes a m6 seat with an H7 housing bore. Journal and housing interface: the 114.3 mm bore takes a m6 shaft seat (upper deviation ~0.229 mm for this diameter range) and the 180.975 mm outside diameter pairs with an H7 housing bore tolerance band of 180.975.000/180.995 mm; the 34.925 mm width defines the shoulder depth, and the 2950 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. From a specification standpoint the 68712 cup is the controlling half of 68450 for housing design — it sets the 180.975 mm OD and the outer abutment diameter — while the 68450 cone controls shaft fit at the 114.3 mm bore; the 34.925 mm width is the result of the two together.SKF 68450 (SKF 68450/68712) is the 68000-series tapered roller choice for a 114.3 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 180.975×34.925 mm envelope.", "applications": [ "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts", "large industrial mixer shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At 114.3 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 68000-series inch series at 114.3 mm bore (180.975×34.925 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 68450 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Do not mix brands or executions inside one 68450 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Catalogue reference speed and limiting speed are different limits: the 2,800 r/min reference is a thermal criterion under load, while the 3,400 r/min limiting value is the mechanical ceiling — observe both.", "The 227/280 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 68450 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 68450/68712 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 68450 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 68000-series code marks the dimensional series. The metric dimensions 114.3×180.975×34.925 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 68450 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (68000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 68450 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 68450 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 68450 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 68450?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 34.925 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "68450-68712-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 114.3×180.975×34.925 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "68450-68712", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "68450-68712" ], "locale_variants": {} }, { "sku": "HH224346-310", "brand": "SKF", "manufacturer_designation": "SKF HH 224346/310", "series": "HH224300-series", "type": "tapered_roller", "d_mm": 114.3, "D_mm": 212.725, "B_mm": 66.675, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 619, "static_load_kN": 830, "fatigue_load_limit_kN": 88, "max_rpm": 3000, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3000, "weight_g": 10000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Mounting practice for HH224346: the rotating cone takes the interference fit (m6 on a 114.3 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Dimensional interchange map: within the HH200 series at 114.3 mm bore, the 212.725 mm OD and 66.675 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 49.2 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 10000 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Cup-side note for 310: the outer ring's rib profile and the 212.725 mm outside diameter are cup-specific within the HH224300-series tables, so substituting a different cup against the same HH 224346 cone changes both the assembled 66.675 mm width and the axial free-play setting of the mounted pair.SKF HH224346 (SKF HH 224346/310) is the HH224300-series tapered roller choice for a 114.3 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 212.725×66.675 mm envelope.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (HH224300-series) ties the pair to a specific boundary plan. Dimensions 114.3×212.725×66.675 mm are the converted metric envelope. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. At 2,200 r/min reference speed the 49.2 mm-section HH224346 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 3,000 r/min as the mechanical ceiling.", "applications": [ "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts", "marine propulsion gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "At 114.3 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The HH224300-series inch series at 114.3 mm bore (212.725×66.675 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HH224346 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common HH224346 mounting error.", "Open HH224346 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 619/830 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HH224346 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HH 224346/310 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does HH224346 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HH224346 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HH224346?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 66.675 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HH224346 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HH224346?", "a": "The SKF HH 224346/310 is a single-row tapered roller bearing with 114.3 mm bore, 212.725 mm outer diameter and 66.675 mm width (4.5 × 8.375 × 2.625 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 619 kN, C0 830 kN, fatigue load limit Pu 88 kN, reference speed 2,200 r/min, limiting speed 3,000 r/min, mass about 10000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HH224346 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HH224300-series code marks the dimensional series. The metric dimensions 114.3×212.725×66.675 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "HH224346-HH224310", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "HH224346-310", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HH224346-310" ], "locale_variants": {} }, { "sku": "938-932", "brand": "SKF", "manufacturer_designation": "SKF 938/932", "series": "935-series", "type": "tapered_roller", "d_mm": 114.3, "D_mm": 212.725, "B_mm": 66.675, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 626, "static_load_kN": 765, "fatigue_load_limit_kN": 81.5, "max_rpm": 3200, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3200, "weight_g": 10000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Fit selection follows the rotating ring — interference on a rotating cone — and two 938 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Journal and housing interface: the 114.3 mm bore takes a m6 shaft seat (upper deviation ~0.229 mm for this diameter range) and the 212.725 mm outside diameter pairs with an H7 housing bore tolerance band of 212.725.000/212.745 mm; the 66.675 mm width defines the shoulder depth, and the 10000 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Two catalogue entries share the 938 cone but use different cups; this one, 938, takes the 932 cup and is ground for the resulting 212.725 mm OD / 66.675 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.In SKF catalogue PUB BU/P1 17000, 938 appears as SKF 938/932: an open, single-row tapered roller bearing in the 935-series, supplied with a pressed-steel cage as standard.Reading the designation: 938 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 935-series code identifies the dimensional series. The 114.3 mm bore, 212.725 mm OD and 66.675 mm width are the metric equivalents of the inch boundary dimensions. In SKF suffix language a bare 938 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 81.5 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.22 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running.", "applications": [ "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes", "wind-turbine main shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At 114.3 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 935-series inch series at 114.3 mm bore (212.725×66.675 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 938 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Do not mix brands or executions inside one 938 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Catalogue reference speed and limiting speed are different limits: the 2,600 r/min reference is a thermal criterion under load, while the 3,200 r/min limiting value is the mechanical ceiling — observe both.", "The 626/765 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 938 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 938/932 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 938 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 938 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 938?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 66.675 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 938 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 938?", "a": "The SKF 938/932 is a single-row tapered roller bearing with 114.3 mm bore, 212.725 mm outer diameter and 66.675 mm width (4.5 × 8.375 × 2.625 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 626 kN, C0 765 kN, fatigue load limit Pu 81.5 kN, reference speed 2,600 r/min, limiting speed 3,200 r/min, mass about 10000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 938 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 935-series code marks the dimensional series. The metric dimensions 114.3×212.725×66.675 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "938-932-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 114.3×212.725×66.675 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "938-932", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "938-932" ], "locale_variants": {} }, { "sku": "HH224349-310", "brand": "SKF", "manufacturer_designation": "SKF HH 224349/310", "series": "HH224300-series", "type": "tapered_roller", "d_mm": 114.975, "D_mm": 212.725, "B_mm": 66.675, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 619, "static_load_kN": 830, "fatigue_load_limit_kN": 88, "max_rpm": 3000, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3000, "weight_g": 10000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " With C 619 kN and C0 830 kN, the HH224349 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 3,000 r/min. Fit selection follows the rotating ring — interference on a rotating cone — and two HH224349 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Cross-section geometry: the 48.9 mm half-section ((212.725−114.975)/2) of this HH200-series unit places the roller large-end pitch diameter at roughly 163 mm, and the 66.675 mm axial width is split between cone (37 mm) and cup rib (30 mm) — a geometry that sets the contact angle and, with the 10000 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Cone versus cup responsibility in HH224349: the HH 224349 cone carries the 114.975 mm bore, rollers and pressed-steel cage; the 310 cup carries the 212.725 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.HH224349 is a single-row tapered roller bearing in the HH224300-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.The HH224300-series series assigns 114.975 mm bore, 212.725 mm OD and 66.675 mm width to HH224349; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "rolling-mill roll-neck bearings" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "At 114.975 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The HH224300-series inch series at 114.975 mm bore (212.725×66.675 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the HH224349 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HH224349 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 212.725 mm cup race release as noise within the first running hours.", "The 619/830 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HH224349 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HH 224349/310 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single HH224349 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HH224349 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HH224349 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HH224349?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 66.675 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HH224349 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HH224349?", "a": "The SKF HH 224349/310 is a single-row tapered roller bearing with 114.975 mm bore, 212.725 mm outer diameter and 66.675 mm width (4.527 × 8.375 × 2.625 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 619 kN, C0 830 kN, fatigue load limit Pu 88 kN, reference speed 2,200 r/min, limiting speed 3,000 r/min, mass about 10000 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "HH224349-310", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HH224349-310" ], "locale_variants": {} }, { "sku": "HM624749-710", "brand": "SKF", "manufacturer_designation": "SKF HM 624749/710", "series": "HM624700-series", "type": "tapered_roller", "d_mm": 120.65, "D_mm": 190.5, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 388, "static_load_kN": 540, "fatigue_load_limit_kN": 56, "max_rpm": 3200, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3200, "weight_g": 4850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF HM 624749/710 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 120.65 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.Numbering ties the bearing to its inch-series envelope: HM624749 means a cone and cup matched pair in the HM624700-series series — which is why the 120.65×190.5×46.038 mm outline swaps dimensionally with other inch-series bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Selection arithmetic: the C0/C ratio is about 1.39 (static 540 kN against dynamic 388 kN), typical of a tapered roller sized for axial capacity, and the 56 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Fit selection follows the rotating ring — interference on a rotating cone — and two HM624749 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Journal and housing interface: the 120.65 mm bore takes a m6 shaft seat (upper deviation ~0.241 mm for this diameter range) and the 190.5 mm outside diameter pairs with an H7 housing bore tolerance band of 190.5.000/190.520 mm; the 46.038 mm width defines the shoulder depth, and the 4850 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Cone versus cup responsibility in HM624749: the HM 624749 cone carries the 120.65 mm bore, rollers and pressed-steel cage; the 710 cup carries the 190.5 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "At 120.65 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The HM624700-series inch series at 120.65 mm bore (190.5×46.038 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common HM624749 mounting error.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the HM624749 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Open HM624749 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 388/540 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM624749 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 624749/710 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of HM624749?", "a": "The SKF HM 624749/710 is a single-row tapered roller bearing with 120.65 mm bore, 190.5 mm outer diameter and 46.038 mm width (4.75 × 7.5 × 1.813 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 388 kN, C0 540 kN, fatigue load limit Pu 56 kN, reference speed 2,600 r/min, limiting speed 3,200 r/min, mass about 4850 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM624749 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM624700-series code marks the dimensional series. The metric dimensions 120.65×190.5×46.038 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM624749 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM624700-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single HM624749 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HM624749 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM624749 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "HM624749-710", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM624749-710" ], "locale_variants": {} }, { "sku": "48290-48220", "brand": "SKF", "manufacturer_designation": "SKF 48290/48220", "series": "48200-series", "type": "tapered_roller", "d_mm": 127, "D_mm": 182.562, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 281, "static_load_kN": 440, "fatigue_load_limit_kN": 44, "max_rpm": 3200, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3200, "weight_g": 3300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Note the minimum-axial-load requirement: at light radial load and high speed the rollers of 48290 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Dimensional interchange map: within the 48200 series at 127 mm bore, the 182.562 mm OD and 39.688 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 27.8 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 3300 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Cup-side note for 48220: the outer ring's rib profile and the 182.562 mm outside diameter are cup-specific within the 48200-series tables, so substituting a different cup against the same 48290 cone changes both the assembled 39.688 mm width and the axial free-play setting of the mounted pair.48290 is a single-row tapered roller bearing in the 48200-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Reading the designation: 48290 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 48200-series code identifies the dimensional series. The 127 mm bore, 182.562 mm OD and 39.688 mm width are the metric equivalents of the inch boundary dimensions. In SKF suffix language a bare 48290 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 44 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.57 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running.", "applications": [ "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes", "wind-turbine main shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At 127 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 48200-series inch series at 127 mm bore (182.562×39.688 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 48290 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Do not mix brands or executions inside one 48290 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 281/440 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 48290 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 48290/48220 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 48290 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 48290 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 48290?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 39.688 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 48290 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 48290?", "a": "The SKF 48290/48220 is a single-row tapered roller bearing with 127 mm bore, 182.562 mm outer diameter and 39.688 mm width (5 × 7.187 × 1.563 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 281 kN, C0 440 kN, fatigue load limit Pu 44 kN, reference speed 2,600 r/min, limiting speed 3,200 r/min, mass about 3300 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 48290 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 48200-series code marks the dimensional series. The metric dimensions 127×182.562×39.688 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "48290-48220-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 127×182.562×39.688 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "48290-48220", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "48290-48220" ], "locale_variants": {} }, { "sku": "67388-67322", "brand": "SKF", "manufacturer_designation": "SKF 67388/67322", "series": "67300-series", "type": "tapered_roller", "d_mm": 127, "D_mm": 196.85, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 395, "static_load_kN": 585, "fatigue_load_limit_kN": 60, "max_rpm": 3000, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3000, "weight_g": 5200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF inch-series tables 67388 sits at 127 mm bore (5 in) with a 196.85 mm cup OD and 46.038 mm total width — dimensions that trace back to the original Timken boundary plan for the 67300-series family. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 5200 g for the 127×196.85×46.038 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. For a 127 mm shaft the usual cone seat is m6 with an H7 housing when the inner ring rotates; arrange two 67388 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Material and manufacturing detail: the 5200 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 67300 ISO envelope, with the pressed-steel cage contributing roughly 156 g of the total; the 127 mm bore is ground to IT5 roundness and the 196.85 mm OD to IT5 cylindricity, and the 46.038 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Why the cup reference matters here: in the 67300-series tables the 67388 cone appears against several cup options. 67388 is the pairing with 67322, and that choice — not the cone — fixes the 196.85 mm OD, the raceway track position and the 46.038 mm assembled width.The SKF 67388/67322 is a 127×196.85×46.038 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.", "applications": [ "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums", "offshore winch and drawworks drums" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "At 127 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 67300-series inch series at 127 mm bore (196.85×46.038 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single 67388 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 67388 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The 5200 g mass and 46.038 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 67388.", "The 395/585 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 67388 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 67388/67322 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 67388 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 67300-series code marks the dimensional series. The metric dimensions 127×196.85×46.038 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 67388 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (67300-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 67388 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 67388 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 67388 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 67388?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 46.038 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "67388-67322-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 127×196.85×46.038 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "67388-67322", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "67388-67322" ], "locale_variants": {} }, { "sku": "798-792", "brand": "SKF", "manufacturer_designation": "SKF 798/792", "series": "795-series", "type": "tapered_roller", "d_mm": 127, "D_mm": 206.375, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 424, "static_load_kN": 585, "fatigue_load_limit_kN": 61, "max_rpm": 3000, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3000, "weight_g": 6100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Because the contact line is tapered, one 798 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 127 mm shaft typically takes a m6 seat with an H7 housing bore. Speed envelope and thermal behaviour: at 2,400 r/min thermal reference, the 127 mm bore shaft runs at a dn of 305k, and the 39.7 mm section dissipates heat through the cup-to-housing contact path; the 3,000 r/min mechanical ceiling reflects cage strength, and the 6100 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cup-side note for 792: the outer ring's rib profile and the 206.375 mm outside diameter are cup-specific within the 795-series tables, so substituting a different cup against the same 798 cone changes both the assembled 47.625 mm width and the axial free-play setting of the mounted pair.In SKF catalogue PUB BU/P1 17000, 798 appears as SKF 798/792: an open, single-row tapered roller bearing in the 795-series, supplied with a pressed-steel cage as standard.On the SKF nameplate, 798 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 795-series marking the dimensional series. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Selection arithmetic: the C0/C ratio is about 1.38 (static 585 kN against dynamic 424 kN), typical of a tapered roller sized for axial capacity, and the 61 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation.", "applications": [ "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums", "large industrial mixer shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "At 127 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 795-series inch series at 127 mm bore (206.375×47.625 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 798 mounting error.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 798 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Open 798 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 424/585 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 798 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 798/792 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 798 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 798 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 798?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 47.625 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 798 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 798?", "a": "The SKF 798/792 is a single-row tapered roller bearing with 127 mm bore, 206.375 mm outer diameter and 47.625 mm width (5 × 8.125 × 1.875 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 424 kN, C0 585 kN, fatigue load limit Pu 61 kN, reference speed 2,400 r/min, limiting speed 3,000 r/min, mass about 6100 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 798 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 795-series code marks the dimensional series. The metric dimensions 127×206.375×47.625 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "798-792", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "798-792" ], "locale_variants": {} }, { "sku": "L327249-210", "brand": "SKF", "manufacturer_designation": "SKF L 327249/210", "series": "L327200-series", "type": "tapered_roller", "d_mm": 133.35, "D_mm": 177.008, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 166, "static_load_kN": 280, "fatigue_load_limit_kN": 28, "max_rpm": 3200, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3200, "weight_g": 1700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Catalogue mass 1700 g for the 133.35×177.008×25.4 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. For a 133.35 mm shaft the usual cone seat is m6 with an H7 housing when the inner ring rotates; arrange two L327249 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Speed envelope and thermal behaviour: at 2,600 r/min thermal reference, the 133.35 mm bore shaft runs at a dn of 347k, and the 21.8 mm section dissipates heat through the cup-to-housing contact path; the 3,200 r/min mechanical ceiling reflects cage strength, and the 1700 g spinning cone contributes gyroscopic moment under rapid speed reversal. Two catalogue entries share the L 327249 cone but use different cups; this one, L327249, takes the 210 cup and is ground for the resulting 177.008 mm OD / 25.4 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.For a 133.35 mm shaft carrying combined load, SKF lists L327249 under catalogue execution SKF L 327249/210: one open single-row tapered roller bearing in the inch L327200-series.In SKF inch-series tables L327249 sits at 133.35 mm bore (5.25 in) with a 177.008 mm cup OD and 25.4 mm total width — dimensions that trace back to the original Timken boundary plan for the L327200-series family. In SKF suffix language a bare L327249 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately.", "applications": [ "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "At 133.35 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The L327200-series inch series at 133.35 mm bore (177.008×25.4 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 166 kN rating of L327249, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 3,200 r/min speed end and heavier preload only where moment stiffness dominates.", "Do not mix brands or executions inside one L327249 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 177.008 mm cup race release as noise within the first running hours.", "The 166/280 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of L327249 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF L 327249/210 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single L327249 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does L327249 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load L327249 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit L327249?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 25.4 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is L327249 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of L327249?", "a": "The SKF L 327249/210 is a single-row tapered roller bearing with 133.35 mm bore, 177.008 mm outer diameter and 25.4 mm width (5.25 × 6.969 × 1 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 166 kN, C0 280 kN, fatigue load limit Pu 28 kN, reference speed 2,600 r/min, limiting speed 3,200 r/min, mass about 1700 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "L327249-L327210", "equiv_brand": "NTN", "level": "partial", "note": "Same 133.35×177.008×25.4 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "L327249-210", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "L327249-210" ], "locale_variants": {} }, { "sku": "67391-67322", "brand": "SKF", "manufacturer_designation": "SKF 67391/67322", "series": "67300-series", "type": "tapered_roller", "d_mm": 133.35, "D_mm": 196.85, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 395, "static_load_kN": 585, "fatigue_load_limit_kN": 60, "max_rpm": 3000, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3000, "weight_g": 4650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Speed planning uses two different ceilings: 2,400 r/min thermal reference and 3,000 r/min mechanical limiting speed. A single 67391 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Journal and housing interface: the 133.35 mm bore takes a m6 shaft seat (upper deviation ~0.267 mm for this diameter range) and the 196.85 mm outside diameter pairs with an H7 housing bore tolerance band of 196.85.000/196.870 mm; the 46.038 mm width defines the shoulder depth, and the 4650 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Cup-side note for 67322: the outer ring's rib profile and the 196.85 mm outside diameter are cup-specific within the 67300-series tables, so substituting a different cup against the same 67391 cone changes both the assembled 46.038 mm width and the axial free-play setting of the mounted pair.Ordering number SKF 67391/67322 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 133.35 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.In SKF inch-series tables 67391 sits at 133.35 mm bore (5.25 in) with a 196.85 mm cup OD and 46.038 mm total width — dimensions that trace back to the original Timken boundary plan for the 67300-series family. In SKF suffix language a bare 67391 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately.", "applications": [ "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "large industrial mixer shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "At 133.35 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 67300-series inch series at 133.35 mm bore (196.85×46.038 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 395 kN rating of 67391, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 3,000 r/min speed end and heavier preload only where moment stiffness dominates.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 67391 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Catalogue reference speed and limiting speed are different limits: the 2,400 r/min reference is a thermal criterion under load, while the 3,000 r/min limiting value is the mechanical ceiling — observe both.", "The 395/585 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 67391 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 67391/67322 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single 67391 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 67391 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 67391 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 67391?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 46.038 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 67391 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 67391?", "a": "The SKF 67391/67322 is a single-row tapered roller bearing with 133.35 mm bore, 196.85 mm outer diameter and 46.038 mm width (5.25 × 7.75 × 1.813 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 395 kN, C0 585 kN, fatigue load limit Pu 60 kN, reference speed 2,400 r/min, limiting speed 3,000 r/min, mass about 4650 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "67391-67322-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 133.35×196.85×46.038 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "67391-67322", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "67391-67322" ], "locale_variants": {} }, { "sku": "95525-95925", "brand": "SKF", "manufacturer_designation": "SKF 95525/95925", "series": "95000-series", "type": "tapered_roller", "d_mm": 133.35, "D_mm": 234.95, "B_mm": 63.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 683, "static_load_kN": 900, "fatigue_load_limit_kN": 91.5, "max_rpm": 2800, "reference_speed_rpm": 2200, "limiting_speed_rpm": 2800, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Within the 95000-series tables, 95525 appears in several rows because SKF lists multiple cup options for the same cone. 95525 is the 95925 variant, with 234.95 mm OD and 63.5 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.The SKF 95525/95925 is a 133.35×234.95×63.5 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (95000-series) ties the pair to a specific boundary plan. Dimensions 133.35×234.95×63.5 mm are the converted metric envelope. In SKF suffix language a bare 95525 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 2,200 r/min reference speed the 50.8 mm-section 95525 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 2,800 r/min as the mechanical ceiling. Mounting practice for 95525: the rotating cone takes the interference fit (m6 on a 133.35 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Speed envelope and thermal behaviour: at 2,200 r/min thermal reference, the 133.35 mm bore shaft runs at a dn of 293k, and the 50.8 mm section dissipates heat through the cup-to-housing contact path; the 2,800 r/min mechanical ceiling reflects cage strength, and the 11000 g spinning cone contributes gyroscopic moment under rapid speed reversal.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "offshore winch and drawworks drums" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "At 133.35 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 95000-series inch series at 133.35 mm bore (234.95×63.5 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one 95525 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 95525 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 683/900 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 95525 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 95525/95925 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 95525 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 95525?", "a": "The SKF 95525/95925 is a single-row tapered roller bearing with 133.35 mm bore, 234.95 mm outer diameter and 63.5 mm width (5.25 × 9.25 × 2.5 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 683 kN, C0 900 kN, fatigue load limit Pu 91.5 kN, reference speed 2,200 r/min, limiting speed 2,800 r/min, mass about 11000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 95525 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 95000-series code marks the dimensional series. The metric dimensions 133.35×234.95×63.5 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 95525 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (95000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 95525 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "95525-95925-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "95525-95925", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "95525-95925" ], "locale_variants": {} }, { "sku": "898-892", "brand": "SKF", "manufacturer_designation": "SKF 898/892", "series": "895-series", "type": "tapered_roller", "d_mm": 139.7, "D_mm": 228.6, "B_mm": 57.15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 578, "static_load_kN": 800, "fatigue_load_limit_kN": 80, "max_rpm": 2800, "reference_speed_rpm": 2200, "limiting_speed_rpm": 2800, "weight_g": 8950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "898 is a single-row tapered roller bearing in the 895-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.Reading the designation: 898 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 895-series code identifies the dimensional series. The 139.7 mm bore, 228.6 mm OD and 57.15 mm width are the metric equivalents of the inch boundary dimensions. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 8950 g for the 139.7×228.6×57.15 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Fit selection follows the rotating ring — interference on a rotating cone — and two 898 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair. Material and manufacturing detail: the 8950 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 89800 ISO envelope, with the pressed-steel cage contributing roughly 269 g of the total; the 139.7 mm bore is ground to IT5 roundness and the 228.6 mm OD to IT5 cylindricity, and the 57.15 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Inch tapered bearings are matched sets, not mix-and-match components: 898 pairs the 898 cone with the 892 cup under the 895-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.", "applications": [ "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "large industrial mixer shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "At 139.7 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 895-series inch series at 139.7 mm bore (228.6×57.15 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 898 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 898 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 578/800 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 898 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 898/892 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 898?", "a": "The SKF 898/892 is a single-row tapered roller bearing with 139.7 mm bore, 228.6 mm outer diameter and 57.15 mm width (5.5 × 9 × 2.25 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 578 kN, C0 800 kN, fatigue load limit Pu 80 kN, reference speed 2,200 r/min, limiting speed 2,800 r/min, mass about 8950 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 898 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 895-series code marks the dimensional series. The metric dimensions 139.7×228.6×57.15 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 898 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (895-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 898 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 898 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 898 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "898-892-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 139.7×228.6×57.15 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "898-892", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "898-892" ], "locale_variants": {} }, { "sku": "HM231132-110", "brand": "SKF", "manufacturer_designation": "SKF HM 231132/110", "series": "HM231100-series", "type": "tapered_roller", "d_mm": 139.7, "D_mm": 236.538, "B_mm": 57.15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 629, "static_load_kN": 850, "fatigue_load_limit_kN": 86.5, "max_rpm": 2600, "reference_speed_rpm": 2200, "limiting_speed_rpm": 2600, "weight_g": 10000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Specify pairs rather than single units wherever thrust reverses: the tapered contact of HM231132 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Material and manufacturing detail: the 10000 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the HM200 ISO envelope, with the pressed-steel cage contributing roughly 300 g of the total; the 139.7 mm bore is ground to IT5 roundness and the 236.538 mm OD to IT5 cylindricity, and the 57.15 mm width tolerance keeps the pair-setting scatter within the ISO preload class. The cup reference 110 is structural, not a suffix: it identifies the outer ring that, combined with the HM 231132 cone, produces the 139.7/236.538/57.15 mm envelope catalogue-listed as HM231132. Quote the cup number in full when ordering — the HM231100-series tables contain other cups that fit the same cone but change the bearing.In SKF catalogue PUB BU/P1 17000, HM231132 appears as SKF HM 231132/110: an open, single-row tapered roller bearing in the HM231100-series, supplied with a pressed-steel cage as standard.The HM231100-series series assigns 139.7 mm bore, 236.538 mm OD and 57.15 mm width to HM231132; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. With C 629 kN and C0 850 kN, the HM231132 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 2,600 r/min.", "applications": [ "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At 139.7 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The HM231100-series inch series at 139.7 mm bore (236.538×57.15 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one HM231132 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "At the 629 kN rating of HM231132, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 2,600 r/min speed end and heavier preload only where moment stiffness dominates.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 236.538 mm cup race release as noise within the first running hours.", "The 629/850 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM231132 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 231132/110 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does HM231132 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM231132 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HM231132?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 57.15 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HM231132 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM231132?", "a": "The SKF HM 231132/110 is a single-row tapered roller bearing with 139.7 mm bore, 236.538 mm outer diameter and 57.15 mm width (5.5 × 9.313 × 2.25 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 629 kN, C0 850 kN, fatigue load limit Pu 86.5 kN, reference speed 2,200 r/min, limiting speed 2,600 r/min, mass about 10000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM231132 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM231100-series code marks the dimensional series. The metric dimensions 139.7×236.538×57.15 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "HM231132-110", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM231132-110" ], "locale_variants": {} }, { "sku": "HM231148-110", "brand": "SKF", "manufacturer_designation": "SKF HM 231148/110", "series": "HM231100-series", "type": "tapered_roller", "d_mm": 149.225, "D_mm": 236.538, "B_mm": 57.15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 629, "static_load_kN": 850, "fatigue_load_limit_kN": 86.5, "max_rpm": 2600, "reference_speed_rpm": 2200, "limiting_speed_rpm": 2600, "weight_g": 9050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Selection arithmetic: the C0/C ratio is about 1.35 (static 850 kN against dynamic 629 kN), typical of a tapered roller sized for axial capacity, and the 86.5 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Mounting practice for HM231148: the rotating cone takes the interference fit (m6 on a 149.225 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Operating context for the 149.225 mm bore: a shaft of this diameter in the xl-bore band typically runs between 119380 and 179070 r/min in real machinery, and the 236.538 mm outside diameter places the housing shoulder at 245 mm outer abutment; the 57.15 mm width and 9050 g mass together set the shaft critical speed and the housing resonance check for this HM200-series envelope. Inch tapered bearings are matched sets, not mix-and-match components: HM231148 pairs the HM 231148 cone with the 110 cup under the HM231100-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.SKF HM 231148/110 belongs to the SKF single-row tapered roller range — the 149.225 mm bore entry in the inch HM231100-series, dimensioned 236.538 mm OD and 57.15 mm wide.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (HM231100-series) ties the pair to a specific boundary plan. Dimensions 149.225×236.538×57.15 mm are the converted metric envelope. In SKF suffix language a bare HM231148 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately.", "applications": [ "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "marine propulsion gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "At 149.225 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The HM231100-series inch series at 149.225 mm bore (236.538×57.15 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the HM231148 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Do not mix brands or executions inside one HM231148 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Catalogue reference speed and limiting speed are different limits: the 2,200 r/min reference is a thermal criterion under load, while the 2,600 r/min limiting value is the mechanical ceiling — observe both.", "The 629/850 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM231148 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 231148/110 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single HM231148 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HM231148 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM231148 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HM231148?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 57.15 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HM231148 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM231148?", "a": "The SKF HM 231148/110 is a single-row tapered roller bearing with 149.225 mm bore, 236.538 mm outer diameter and 57.15 mm width (5.875 × 9.313 × 2.25 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 629 kN, C0 850 kN, fatigue load limit Pu 86.5 kN, reference speed 2,200 r/min, limiting speed 2,600 r/min, mass about 9050 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "HM231148-110", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM231148-110" ], "locale_variants": {} }, { "sku": "LM330448-410", "brand": "SKF", "manufacturer_designation": "SKF LM 330448/410", "series": "LM330400-series", "type": "tapered_roller", "d_mm": 152.4, "D_mm": 203.2, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 251, "static_load_kN": 480, "fatigue_load_limit_kN": 45.5, "max_rpm": 2800, "reference_speed_rpm": 2400, "limiting_speed_rpm": 2800, "weight_g": 3700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 3700 g for the 152.4×203.2×41.275 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Because the contact line is tapered, one LM330448 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 152.4 mm shaft typically takes a m6 seat with an H7 housing bore. Speed envelope and thermal behaviour: at 2,400 r/min thermal reference, the 152.4 mm bore shaft runs at a dn of 366k, and the 25.4 mm section dissipates heat through the cup-to-housing contact path; the 2,800 r/min mechanical ceiling reflects cage strength, and the 3700 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cone versus cup responsibility in LM330448: the LM 330448 cone carries the 152.4 mm bore, rollers and pressed-steel cage; the 410 cup carries the 203.2 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.For a 152.4 mm shaft carrying combined load, SKF lists LM330448 under catalogue execution SKF LM 330448/410: one open single-row tapered roller bearing in the inch LM330400-series.On the SKF nameplate, LM330448 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the LM330400-series marking the dimensional series.", "applications": [ "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts", "rolling-mill roll-neck bearings" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At 152.4 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The LM330400-series inch series at 152.4 mm bore (203.2×41.275 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one LM330448 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Setting is a design value, not an assembly feel: excessive preload in the LM330448 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The 3700 g mass and 41.275 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of LM330448.", "The 251/480 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM330448 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 330448/410 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in LM330448 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM330400-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM330448 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM330448 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM330448 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM330448?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 41.275 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM330448 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "LM330448-410", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM330448-410" ], "locale_variants": {} }, { "sku": "M231649-610", "brand": "SKF", "manufacturer_designation": "SKF M 231649/610", "series": "M231600-series", "type": "tapered_roller", "d_mm": 152.4, "D_mm": 222.25, "B_mm": 46.83, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 400, "static_load_kN": 630, "fatigue_load_limit_kN": 62, "max_rpm": 2600, "reference_speed_rpm": 2200, "limiting_speed_rpm": 2600, "weight_g": 5850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Journal and housing interface: the 152.4 mm bore takes a m6 shaft seat (upper deviation ~0.305 mm for this diameter range) and the 222.25 mm outside diameter pairs with an H7 housing bore tolerance band of 222.25.000/222.270 mm; the 46.83 mm width defines the shoulder depth, and the 5850 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Cup-side note for 610: the outer ring's rib profile and the 222.25 mm outside diameter are cup-specific within the M231600-series tables, so substituting a different cup against the same M 231649 cone changes both the assembled 46.83 mm width and the axial free-play setting of the mounted pair.In SKF catalogue PUB BU/P1 17000, M231649 appears as SKF M 231649/610: an open, single-row tapered roller bearing in the M231600-series, supplied with a pressed-steel cage as standard.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (M231600-series) ties the pair to a specific boundary plan. Dimensions 152.4×222.25×46.83 mm are the converted metric envelope. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 5850 g for the 152.4×222.25×46.83 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. A single M231649 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel.", "applications": [ "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At 152.4 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The M231600-series inch series at 152.4 mm bore (222.25×46.83 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the M231649 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "A single M231649 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "Open M231649 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 400/630 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of M231649 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF M 231649/610 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit M231649?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 46.83 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is M231649 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of M231649?", "a": "The SKF M 231649/610 is a single-row tapered roller bearing with 152.4 mm bore, 222.25 mm outer diameter and 46.83 mm width (6 × 8.75 × 1.844 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 400 kN, C0 630 kN, fatigue load limit Pu 62 kN, reference speed 2,200 r/min, limiting speed 2,600 r/min, mass about 5850 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the M231649 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the M231600-series code marks the dimensional series. The metric dimensions 152.4×222.25×46.83 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in M231649 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (M231600-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "M231649-610", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "M231649-610" ], "locale_variants": {} }, { "sku": "L432348-310", "brand": "SKF", "manufacturer_designation": "SKF L 432348/310", "series": "L432300-series", "type": "tapered_roller", "d_mm": 158.75, "D_mm": 205.583, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 168, "static_load_kN": 280, "fatigue_load_limit_kN": 27, "max_rpm": 2800, "reference_speed_rpm": 2200, "limiting_speed_rpm": 2800, "weight_g": 1900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Speed planning uses two different ceilings: 2,200 r/min thermal reference and 2,800 r/min mechanical limiting speed. A single L432348 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Speed envelope and thermal behaviour: at 2,200 r/min thermal reference, the 158.75 mm bore shaft runs at a dn of 349k, and the 23.4 mm section dissipates heat through the cup-to-housing contact path; the 2,800 r/min mechanical ceiling reflects cage strength, and the 1900 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cup-side note for 310: the outer ring's rib profile and the 205.583 mm outside diameter are cup-specific within the L432300-series tables, so substituting a different cup against the same L 432348 cone changes both the assembled 23.812 mm width and the axial free-play setting of the mounted pair.In SKF catalogue PUB BU/P1 17000, L432348 appears as SKF L 432348/310: an open, single-row tapered roller bearing in the L432300-series, supplied with a pressed-steel cage as standard.Numbering ties the bearing to its inch-series envelope: L432348 means a cone and cup matched pair in the L432300-series series — which is why the 158.75×205.583×23.812 mm outline swaps dimensionally with other inch-series bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers.", "applications": [ "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "large industrial mixer shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "At 158.75 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The L432300-series inch series at 158.75 mm bore (205.583×23.812 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of L432348 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "A single L432348 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The L432348 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 168/280 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of L432348 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF L 432348/310 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single L432348 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does L432348 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load L432348 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit L432348?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 23.812 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is L432348 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of L432348?", "a": "The SKF L 432348/310 is a single-row tapered roller bearing with 158.75 mm bore, 205.583 mm outer diameter and 23.812 mm width (6.25 × 8.094 × 0.937 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 168 kN, C0 280 kN, fatigue load limit Pu 27 kN, reference speed 2,200 r/min, limiting speed 2,800 r/min, mass about 1900 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "L432348-310", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "L432348-310" ], "locale_variants": {} }, { "sku": "L432349-310", "brand": "SKF", "manufacturer_designation": "SKF L 432349/310", "series": "L432300-series", "type": "tapered_roller", "d_mm": 158.75, "D_mm": 205.583, "B_mm": 23.813, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 168, "static_load_kN": 280, "fatigue_load_limit_kN": 27, "max_rpm": 2800, "reference_speed_rpm": 2200, "limiting_speed_rpm": 2800, "weight_g": 1950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Cross-section geometry: the 23.4 mm half-section ((205.583−158.75)/2) of this L4300-series unit places the roller large-end pitch diameter at roughly 182 mm, and the 23.813 mm axial width is split between cone (13 mm) and cup rib (11 mm) — a geometry that sets the contact angle and, with the 1950 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Why the cup reference matters here: in the L432300-series tables the L 432349 cone appears against several cup options. L432349 is the pairing with 310, and that choice — not the cone — fixes the 205.583 mm OD, the raceway track position and the 23.813 mm assembled width.SKF L432349 (SKF L 432349/310) is the L432300-series tapered roller choice for a 158.75 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 205.583×23.813 mm envelope.On the SKF nameplate, L432349 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the L432300-series marking the dimensional series. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Selection arithmetic: the C0/C ratio is about 1.67 (static 280 kN against dynamic 168 kN), typical of a tapered roller sized for axial capacity, and the 27 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Mounting practice for L432349: the rotating cone takes the interference fit (m6 on a 158.75 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing.", "applications": [ "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "At 158.75 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The L432300-series inch series at 158.75 mm bore (205.583×23.813 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 168 kN rating of L432349, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 2,800 r/min speed end and heavier preload only where moment stiffness dominates.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common L432349 mounting error.", "Catalogue reference speed and limiting speed are different limits: the 2,200 r/min reference is a thermal criterion under load, while the 2,800 r/min limiting value is the mechanical ceiling — observe both.", "The 168/280 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of L432349 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF L 432349/310 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit L432349?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 23.813 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is L432349 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of L432349?", "a": "The SKF L 432349/310 is a single-row tapered roller bearing with 158.75 mm bore, 205.583 mm outer diameter and 23.813 mm width (6.25 × 8.094 × 0.938 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 168 kN, C0 280 kN, fatigue load limit Pu 27 kN, reference speed 2,200 r/min, limiting speed 2,800 r/min, mass about 1950 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the L432349 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the L432300-series code marks the dimensional series. The metric dimensions 158.75×205.583×23.813 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in L432349 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (L432300-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "L432349-L432310", "equiv_brand": "NTN", "level": "partial", "note": "Same 158.75×205.583×23.813 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "L432349-310", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "L432349-310" ], "locale_variants": {} }, { "sku": "HH437549-510", "brand": "SKF", "manufacturer_designation": "SKF HH 437549/510", "series": "HH437500-series", "type": "tapered_roller", "d_mm": 165.1, "D_mm": 336.55, "B_mm": 92.075, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1198, "static_load_kN": 1700, "fatigue_load_limit_kN": 156, "max_rpm": 1900, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1900, "weight_g": 37000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 1198 kN and C0 1700 kN, the HH437549 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 1,900 r/min. Specify pairs rather than single units wherever thrust reverses: the tapered contact of HH437549 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Journal and housing interface: the 165.1 mm bore takes a m6 shaft seat (upper deviation ~0.330 mm for this diameter range) and the 336.55 mm outside diameter pairs with an H7 housing bore tolerance band of 336.55.000/336.570 mm; the 92.075 mm width defines the shoulder depth, and the 37000 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in HH437549 the HH 437549 cone contributes the 165.1 mm bore and roller set, the 510 cup contributes the 336.55 mm OD raceway, and the assembled 92.075 mm width is the catalogue value.SKF HH437549 (SKF HH 437549/510) is the HH437500-series tapered roller choice for a 165.1 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 336.55×92.075 mm envelope.In SKF inch-series tables HH437549 sits at 165.1 mm bore (6.5 in) with a 336.55 mm cup OD and 92.075 mm total width — dimensions that trace back to the original Timken boundary plan for the HH437500-series family.", "applications": [ "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes", "offshore winch and drawworks drums" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At 165.1 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The HH437500-series inch series at 165.1 mm bore (336.55×92.075 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common HH437549 mounting error.", "Setting is a design value, not an assembly feel: excessive preload in the HH437549 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Shaft and housing fillets must clear the bearing chamfer so the 92.075 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 1198/1700 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HH437549 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HH 437549/510 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in HH437549 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HH437500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single HH437549 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HH437549 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HH437549 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit HH437549?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 92.075 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HH437549 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "HH437549-510", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HH437549-510" ], "locale_variants": {} }, { "sku": "36990-36920", "brand": "SKF", "manufacturer_designation": "SKF 36990/36920", "series": "36900-series", "type": "tapered_roller", "d_mm": 177.8, "D_mm": 227.012, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 231, "static_load_kN": 425, "fatigue_load_limit_kN": 40, "max_rpm": 2400, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2400, "weight_g": 2950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Cup-side note for 36920: the outer ring's rib profile and the 227.012 mm outside diameter are cup-specific within the 36900-series tables, so substituting a different cup against the same 36990 cone changes both the assembled 30.162 mm width and the axial free-play setting of the mounted pair.In SKF catalogue PUB BU/P1 17000, 36990 appears as SKF 36990/36920: an open, single-row tapered roller bearing in the 36900-series, supplied with a pressed-steel cage as standard.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (36900-series) ties the pair to a specific boundary plan. Dimensions 177.8×227.012×30.162 mm are the converted metric envelope. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 231 kN and C0 425 kN, the 36990 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 2,400 r/min. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 36990 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Load system: the 231 kN basic dynamic rating C and 425 kN static rating C0 give a C0/C balance of 1.84, and dividing C by the 177.8 mm bore yields 1.30 kN per millimetre of journal — a density metric that compares across families; the 40 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 177.8 mm shaft carrying variable duty.", "applications": [ "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "wind-turbine main shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "At 177.8 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 320 series at 177.8 mm bore (227.012×30.162 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "Do not mix brands or executions inside one 36990 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "At the 231 kN rating of 36990, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 2,400 r/min speed end and heavier preload only where moment stiffness dominates.", "Shaft and housing fillets must clear the bearing chamfer so the 30.162 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 231/425 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 36990 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 36990/36920 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 36990 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 36990?", "a": "The SKF 36990/36920 is a single-row tapered roller bearing with 177.8 mm bore, 227.012 mm outer diameter and 30.162 mm width (7 × 8.937 × 1.187 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 231 kN, C0 425 kN, fatigue load limit Pu 40 kN, reference speed 2,000 r/min, limiting speed 2,400 r/min, mass about 2950 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 36990 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 36900-series code marks the dimensional series. The metric dimensions 177.8×227.012×30.162 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 36990 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (36900-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 36990 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "36990-36920-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 177.8×227.012×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "36990-36920", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "36990-36920" ], "locale_variants": {} }, { "sku": "94700-94113", "brand": "SKF", "manufacturer_designation": "SKF 94700/94113", "series": "94000-series", "type": "tapered_roller", "d_mm": 177.8, "D_mm": 288.925, "B_mm": 63.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 774, "static_load_kN": 1140, "fatigue_load_limit_kN": 108, "max_rpm": 2000, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2000, "weight_g": 16000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 177.8 mm shaft carrying combined load, SKF lists 94700 under catalogue execution SKF 94700/94113: one open single-row tapered roller bearing in the inch 94000-series.Reading the designation: 94700 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the 94000-series code identifies the dimensional series. The 177.8 mm bore, 288.925 mm OD and 63.5 mm width are the metric equivalents of the inch boundary dimensions. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Selection arithmetic: the C0/C ratio is about 1.47 (static 1140 kN against dynamic 774 kN), typical of a tapered roller sized for axial capacity, and the 108 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. For a 177.8 mm shaft the usual cone seat is m6 with an H7 housing when the inner ring rotates; arrange two 94700 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Cross-section geometry: the 55.6 mm half-section ((288.925−177.8)/2) of this 94700-series unit places the roller large-end pitch diameter at roughly 233 mm, and the 63.5 mm axial width is split between cone (35 mm) and cup rib (29 mm) — a geometry that sets the contact angle and, with the 16000 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Within the 94000-series tables, 94700 appears in several rows because SKF lists multiple cup options for the same cone. 94700 is the 94113 variant, with 288.925 mm OD and 63.5 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "At 177.8 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 94000-series inch series at 177.8 mm bore (288.925×63.5 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 94700 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Do not mix brands or executions inside one 94700 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 774/1140 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 94700 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 94700/94113 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of 94700?", "a": "The SKF 94700/94113 is a single-row tapered roller bearing with 177.8 mm bore, 288.925 mm outer diameter and 63.5 mm width (7 × 11.375 × 2.5 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 774 kN, C0 1140 kN, fatigue load limit Pu 108 kN, reference speed 1,700 r/min, limiting speed 2,000 r/min, mass about 16000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 94700 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 94000-series code marks the dimensional series. The metric dimensions 177.8×288.925×63.5 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 94700 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (94000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 94700 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 94700 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 94700 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "94700-94113", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "94700-94113" ], "locale_variants": {} }, { "sku": "M336948-912", "brand": "SKF", "manufacturer_designation": "SKF M 336948/912", "series": "M336900-series", "type": "tapered_roller", "d_mm": 178.595, "D_mm": 265.112, "B_mm": 51.595, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 532, "static_load_kN": 880, "fatigue_load_limit_kN": 85, "max_rpm": 2200, "reference_speed_rpm": 1800, "limiting_speed_rpm": 2200, "weight_g": 9550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 178.595 mm shaft carrying combined load, SKF lists M336948 under catalogue execution SKF M 336948/912: one open single-row tapered roller bearing in the inch M336900-series.On the SKF nameplate, M336948 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the M336900-series marking the dimensional series. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Selection arithmetic: the C0/C ratio is about 1.65 (static 880 kN against dynamic 532 kN), typical of a tapered roller sized for axial capacity, and the 85 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Specify pairs rather than single units wherever thrust reverses: the tapered contact of M336948 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Journal and housing interface: the 178.595 mm bore takes a m6 shaft seat (upper deviation ~0.357 mm for this diameter range) and the 265.112 mm outside diameter pairs with an H7 housing bore tolerance band of 265.112.000/265.132 mm; the 51.595 mm width defines the shoulder depth, and the 9550 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in M336948 the M 336948 cone contributes the 178.595 mm bore and roller set, the 912 cup contributes the 265.112 mm OD raceway, and the assembled 51.595 mm width is the catalogue value.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "At 178.595 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The M336900-series inch series at 178.595 mm bore (265.112×51.595 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of M336948 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of M336948 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The 9550 g mass and 51.595 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of M336948.", "The 532/880 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of M336948 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF M 336948/912 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of M336948?", "a": "The SKF M 336948/912 is a single-row tapered roller bearing with 178.595 mm bore, 265.112 mm outer diameter and 51.595 mm width (7.031 × 10.437 × 2.031 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 532 kN, C0 880 kN, fatigue load limit Pu 85 kN, reference speed 1,800 r/min, limiting speed 2,200 r/min, mass about 9550 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the M336948 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the M336900-series code marks the dimensional series. The metric dimensions 178.595×265.112×51.595 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in M336948 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (M336900-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single M336948 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does M336948 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load M336948 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "M336948-912", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "M336948-912" ], "locale_variants": {} }, { "sku": "M336949-912", "brand": "SKF", "manufacturer_designation": "SKF M 336949/912", "series": "M336900-series", "type": "tapered_roller", "d_mm": 179.934, "D_mm": 265.112, "B_mm": 51.595, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 532, "static_load_kN": 880, "fatigue_load_limit_kN": 85, "max_rpm": 2200, "reference_speed_rpm": 1800, "limiting_speed_rpm": 2200, "weight_g": 9400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " In SKF suffix language a bare M336949 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 1,800 r/min reference speed the 42.6 mm-section M336949 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 2,200 r/min as the mechanical ceiling. A single M336949 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Cross-section geometry: the 42.6 mm half-section ((265.112−179.934)/2) of this M3300-series unit places the roller large-end pitch diameter at roughly 222 mm, and the 51.595 mm axial width is split between cone (28 mm) and cup rib (23 mm) — a geometry that sets the contact angle and, with the 9400 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Cone-and-cup identity in M336949: the leading M 336949 reference identifies the inner ring, rollers and cage; the trailing 912 reference identifies the outer ring. The M336900-series series lists alternative cups for the same cone, each producing a different 265.112 mm OD or 51.595 mm width — hence a different SKU even though the bore stays at 179.934 mm.M336949 is a single-row tapered roller bearing in the M336900-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (M336900-series) ties the pair to a specific boundary plan. Dimensions 179.934×265.112×51.595 mm are the converted metric envelope.", "applications": [ "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "large crusher and mineral-processing drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "At 179.934 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The M336900-series inch series at 179.934 mm bore (265.112×51.595 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 532 kN rating of M336949, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 2,200 r/min speed end and heavier preload only where moment stiffness dominates.", "Setting is a design value, not an assembly feel: excessive preload in the M336949 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 532/880 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of M336949 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF M 336949/912 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in M336949 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (M336900-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single M336949 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does M336949 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load M336949 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit M336949?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 51.595 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is M336949 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "M336949-912", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "M336949-912" ], "locale_variants": {} }, { "sku": "87737-87111", "brand": "SKF", "manufacturer_designation": "SKF 87737/87111", "series": "87000-series", "type": "tapered_roller", "d_mm": 187.325, "D_mm": 282.575, "B_mm": 50.8, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 427, "static_load_kN": 695, "fatigue_load_limit_kN": 67, "max_rpm": 2000, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2000, "weight_g": 9900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Because the contact line is tapered, one 87737 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 187.325 mm shaft typically takes a m6 seat with an H7 housing bore. Cross-section geometry: the 47.6 mm half-section ((282.575−187.325)/2) of this 87700-series unit places the roller large-end pitch diameter at roughly 234 mm, and the 50.8 mm axial width is split between cone (28 mm) and cup rib (23 mm) — a geometry that sets the contact angle and, with the 9900 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Inch tapered bearings are matched sets, not mix-and-match components: 87737 pairs the 87737 cone with the 87111 cup under the 87000-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.SKF 87737/87111 belongs to the SKF single-row tapered roller range — the 187.325 mm bore entry in the inch 87000-series, dimensioned 282.575 mm OD and 50.8 mm wide.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (87000-series) ties the pair to a specific boundary plan. Dimensions 187.325×282.575×50.8 mm are the converted metric envelope. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Selection arithmetic: the C0/C ratio is about 1.63 (static 695 kN against dynamic 427 kN), typical of a tapered roller sized for axial capacity, and the 67 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation.", "applications": [ "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums", "large industrial mixer shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At 187.325 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 87000-series inch series at 187.325 mm bore (282.575×50.8 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 87737 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 87737 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 427/695 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 87737 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 87737/87111 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 87737 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 87737 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 87737?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 50.8 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 87737 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 87737?", "a": "The SKF 87737/87111 is a single-row tapered roller bearing with 187.325 mm bore, 282.575 mm outer diameter and 50.8 mm width (7.375 × 11.125 × 2 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 427 kN, C0 695 kN, fatigue load limit Pu 67 kN, reference speed 1,700 r/min, limiting speed 2,000 r/min, mass about 9900 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 87737 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 87000-series code marks the dimensional series. The metric dimensions 187.325×282.575×50.8 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "87737-87111", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "87737-87111" ], "locale_variants": {} }, { "sku": "M239447-410", "brand": "SKF", "manufacturer_designation": "SKF M 239447/410", "series": "M239400-series", "type": "tapered_roller", "d_mm": 189.738, "D_mm": 279.4, "B_mm": 52.388, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 643, "static_load_kN": 980, "fatigue_load_limit_kN": 93, "max_rpm": 2000, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2000, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " A single M239447 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Journal and housing interface: the 189.738 mm bore takes a m6 shaft seat (upper deviation ~0.379 mm for this diameter range) and the 279.4 mm outside diameter pairs with an H7 housing bore tolerance band of 279.4.000/279.420 mm; the 52.388 mm width defines the shoulder depth, and the 11000 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Cone-and-cup identity in M239447: the leading M 239447 reference identifies the inner ring, rollers and cage; the trailing 410 reference identifies the outer ring. The M239400-series series lists alternative cups for the same cone, each producing a different 279.4 mm OD or 52.388 mm width — hence a different SKU even though the bore stays at 189.738 mm.SKF M239447 (SKF M 239447/410) is the M239400-series tapered roller choice for a 189.738 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 279.4×52.388 mm envelope.Digit by digit, M239447 reads as cone reference / cup reference in the M239400-series inch series; the 189.738 mm bore, 279.4 mm OD and 52.388 mm width are the metric equivalents of the original inch boundary values. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 643 kN and C0 980 kN, the M239447 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 2,000 r/min.", "applications": [ "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "At 189.738 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The M239400-series inch series at 189.738 mm bore (279.4×52.388 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 643 kN rating of M239447, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 2,000 r/min speed end and heavier preload only where moment stiffness dominates.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the M239447 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The 11000 g mass and 52.388 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of M239447.", "The 643/980 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of M239447 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF M 239447/410 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does M239447 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load M239447 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit M239447?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 52.388 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is M239447 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of M239447?", "a": "The SKF M 239447/410 is a single-row tapered roller bearing with 189.738 mm bore, 279.4 mm outer diameter and 52.388 mm width (7.47 × 11 × 2.063 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 643 kN, C0 980 kN, fatigue load limit Pu 93 kN, reference speed 1,700 r/min, limiting speed 2,000 r/min, mass about 11000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the M239447 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the M239400-series code marks the dimensional series. The metric dimensions 189.738×279.4×52.388 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "M239447-410", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "M239447-410" ], "locale_variants": {} }, { "sku": "87750-87111", "brand": "SKF", "manufacturer_designation": "SKF 87750/87111", "series": "87000-series", "type": "tapered_roller", "d_mm": 190.5, "D_mm": 282.575, "B_mm": 50.8, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 427, "static_load_kN": 695, "fatigue_load_limit_kN": 67, "max_rpm": 2000, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2000, "weight_g": 9550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Housing and abutment design flows from the cup: in 87750 the 87111 cup fixes the 282.575 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the 87750 cone determines the 190.5 mm shaft interface; the 50.8 mm width is the assembled pair value.For a 190.5 mm shaft carrying combined load, SKF lists 87750 under catalogue execution SKF 87750/87111: one open single-row tapered roller bearing in the inch 87000-series.The 87000-series series assigns 190.5 mm bore, 282.575 mm OD and 50.8 mm width to 87750; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. In SKF suffix language a bare 87750 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 1,700 r/min reference speed the 46.0 mm-section 87750 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 2,000 r/min as the mechanical ceiling. Mounting practice for 87750: the rotating cone takes the interference fit (m6 on a 190.5 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Cross-section geometry: the 46.0 mm half-section ((282.575−190.5)/2) of this 87700-series unit places the roller large-end pitch diameter at roughly 236 mm, and the 50.8 mm axial width is split between cone (28 mm) and cup rib (23 mm) — a geometry that sets the contact angle and, with the 9550 g rotating cone mass, the critical speed at which cage-roller imbalance begins.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "offshore winch and drawworks drums" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At 190.5 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 87000-series inch series at 190.5 mm bore (282.575×50.8 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 87750 mounting error.", "A single 87750 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The 9550 g mass and 50.8 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 87750.", "The 427/695 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 87750 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 87750/87111 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 87750 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 87750?", "a": "The SKF 87750/87111 is a single-row tapered roller bearing with 190.5 mm bore, 282.575 mm outer diameter and 50.8 mm width (7.5 × 11.125 × 2 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 427 kN, C0 695 kN, fatigue load limit Pu 67 kN, reference speed 1,700 r/min, limiting speed 2,000 r/min, mass about 9550 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 87750 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 87000-series code marks the dimensional series. The metric dimensions 190.5×282.575×50.8 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 87750 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (87000-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 87750 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "87750-87111", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "87750-87111" ], "locale_variants": {} }, { "sku": "LL639249-210", "brand": "SKF", "manufacturer_designation": "SKF LL 639249/210", "series": "LL639200-series", "type": "tapered_roller", "d_mm": 196.85, "D_mm": 241.3, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 189, "static_load_kN": 315, "fatigue_load_limit_kN": 29, "max_rpm": 2400, "reference_speed_rpm": 1900, "limiting_speed_rpm": 2400, "weight_g": 2100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF LL 639249/210 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 196.85 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.In SKF inch-series tables LL639249 sits at 196.85 mm bore (7.75 in) with a 241.3 mm cup OD and 23.812 mm total width — dimensions that trace back to the original Timken boundary plan for the LL639200-series family. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Selection arithmetic: the C0/C ratio is about 1.67 (static 315 kN against dynamic 189 kN), typical of a tapered roller sized for axial capacity, and the 29 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Because the contact line is tapered, one LL639249 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 196.85 mm shaft typically takes a m6 seat with an H7 housing bore. Cross-section geometry: the 22.2 mm half-section ((241.3−196.85)/2) of this LL600-series unit places the roller large-end pitch diameter at roughly 219 mm, and the 23.812 mm axial width is split between cone (13 mm) and cup rib (11 mm) — a geometry that sets the contact angle and, with the 2100 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Inch tapered bearings are matched sets, not mix-and-match components: LL639249 pairs the LL 639249 cone with the 210 cup under the LL639200-series boundary plan, and although the same cone shows up against other cups in the catalogue, each pairing yields a distinct assembled width and a distinct rating row.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "At 196.85 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The LL639200-series inch series at 196.85 mm bore (241.3×23.812 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one LL639249 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "A single LL639249 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 189/315 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LL639249 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LL 639249/210 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of LL639249?", "a": "The SKF LL 639249/210 is a single-row tapered roller bearing with 196.85 mm bore, 241.3 mm outer diameter and 23.812 mm width (7.75 × 9.5 × 0.937 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 189 kN, C0 315 kN, fatigue load limit Pu 29 kN, reference speed 1,900 r/min, limiting speed 2,400 r/min, mass about 2100 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LL639249 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LL639200-series code marks the dimensional series. The metric dimensions 196.85×241.3×23.812 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LL639249 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LL639200-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LL639249 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LL639249 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LL639249 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "LL639249-LL639210", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "LL639249-210", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LL639249-210" ], "locale_variants": {} }, { "sku": "LM739749-710", "brand": "SKF", "manufacturer_designation": "SKF LM 739749/710", "series": "LM739700-series", "type": "tapered_roller", "d_mm": 196.85, "D_mm": 257.175, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 339, "static_load_kN": 655, "fatigue_load_limit_kN": 58.5, "max_rpm": 2200, "reference_speed_rpm": 1800, "limiting_speed_rpm": 2200, "weight_g": 5350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Housing and abutment design flows from the cup: in LM739749 the 710 cup fixes the 257.175 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the LM 739749 cone determines the 196.85 mm shaft interface; the 39.688 mm width is the assembled pair value.In SKF catalogue PUB BU/P1 17000, LM739749 appears as SKF LM 739749/710: an open, single-row tapered roller bearing in the LM739700-series, supplied with a pressed-steel cage as standard.Digit by digit, LM739749 reads as cone reference / cup reference in the LM739700-series inch series; the 196.85 mm bore, 257.175 mm OD and 39.688 mm width are the metric equivalents of the original inch boundary values. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Selection arithmetic: the C0/C ratio is about 1.93 (static 655 kN against dynamic 339 kN), typical of a tapered roller sized for axial capacity, and the 58.5 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. For a 196.85 mm shaft the usual cone seat is m6 with an H7 housing when the inner ring rotates; arrange two LM739749 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Dimensional interchange map: within the LM700 series at 196.85 mm bore, the 257.175 mm OD and 39.688 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 30.2 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 5350 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes", "rolling-mill roll-neck bearings" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At 196.85 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The LM739700-series inch series at 196.85 mm bore (257.175×39.688 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of LM739749 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of LM739749 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Open LM739749 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 339/655 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM739749 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 739749/710 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is LM739749 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM739749?", "a": "The SKF LM 739749/710 is a single-row tapered roller bearing with 196.85 mm bore, 257.175 mm outer diameter and 39.688 mm width (7.75 × 10.125 × 1.563 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 339 kN, C0 655 kN, fatigue load limit Pu 58.5 kN, reference speed 1,800 r/min, limiting speed 2,200 r/min, mass about 5350 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM739749 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM739700-series code marks the dimensional series. The metric dimensions 196.85×257.175×39.688 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM739749 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM739700-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM739749 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "LM739749-710", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM739749-710" ], "locale_variants": {} }, { "sku": "67981-67919", "brand": "SKF", "manufacturer_designation": "SKF 67981/67919", "series": "67900-series", "type": "tapered_roller", "d_mm": 198.298, "D_mm": 279.4, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 465, "static_load_kN": 830, "fatigue_load_limit_kN": 76.5, "max_rpm": 2000, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2000, "weight_g": 9200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The 67900-series series assigns 198.298 mm bore, 279.4 mm OD and 46.038 mm width to 67981; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. In SKF suffix language a bare 67981 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 1.78 (static 830 kN against dynamic 465 kN), typical of a tapered roller sized for axial capacity, and the 76.5 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 67981 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Operating context for the 198.298 mm bore: a shaft of this diameter in the xl-bore band typically runs between 158638 and 237958 r/min in real machinery, and the 279.4 mm outside diameter places the housing shoulder at 287 mm outer abutment; the 46.038 mm width and 9200 g mass together set the shaft critical speed and the housing resonance check for this 67900-series envelope. Cup-side note for 67919: the outer ring's rib profile and the 279.4 mm outside diameter are cup-specific within the 67900-series tables, so substituting a different cup against the same 67981 cone changes both the assembled 46.038 mm width and the axial free-play setting of the mounted pair.Ordering number SKF 67981/67919 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 198.298 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.", "applications": [ "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "large crusher and mineral-processing drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "At 198.298 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 67900-series inch series at 198.298 mm bore (279.4×46.038 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the 67981 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Do not mix brands or executions inside one 67981 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 279.4 mm cup race release as noise within the first running hours.", "The 465/830 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 67981 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 67981/67919 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 67981 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 67900-series code marks the dimensional series. The metric dimensions 198.298×279.4×46.038 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 67981 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (67900-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 67981 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 67981 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 67981 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 67981?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 46.038 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "67981-67919", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "67981-67919" ], "locale_variants": {} }, { "sku": "67982-67919", "brand": "SKF", "manufacturer_designation": "SKF 67982/67919", "series": "67900-series", "type": "tapered_roller", "d_mm": 199.949, "D_mm": 279.4, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 465, "static_load_kN": 830, "fatigue_load_limit_kN": 76.5, "max_rpm": 2000, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2000, "weight_g": 9000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "On the SKF nameplate, 67982 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 67900-series marking the dimensional series. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 39.7 mm radial section height ((279.4−199.949)/2) and 9000 g catalogue mass frame a 199.949 mm bore bearing rated at 465 kN C — roughly 2.33 kN of dynamic capacity per millimetre of bore before application factors. Because the contact line is tapered, one 67982 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 199.949 mm shaft typically takes a m6 seat with an H7 housing bore. Material and manufacturing detail: the 9000 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 67900 ISO envelope, with the pressed-steel cage contributing roughly 270 g of the total; the 199.949 mm bore is ground to IT5 roundness and the 279.4 mm OD to IT5 cylindricity, and the 46.038 mm width tolerance keeps the pair-setting scatter within the ISO preload class. The cup reference 67919 is structural, not a suffix: it identifies the outer ring that, combined with the 67982 cone, produces the 199.949/279.4/46.038 mm envelope catalogue-listed as 67982. Quote the cup number in full when ordering — the 67900-series tables contain other cups that fit the same cone but change the bearing.67982 is a single-row tapered roller bearing in the 67900-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.", "applications": [ "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes", "marine propulsion gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "At 199.949 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 67900-series inch series at 199.949 mm bore (279.4×46.038 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 67982 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 67982 mounting error.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 465/830 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 67982 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 67982/67919 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the 67982 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 67900-series code marks the dimensional series. The metric dimensions 199.949×279.4×46.038 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 67982 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (67900-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 67982 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does 67982 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 67982 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 67982?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 46.038 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "67982-67919", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "67982-67919" ], "locale_variants": {} }, { "sku": "LM241147-110", "brand": "SKF", "manufacturer_designation": "SKF LM 241147/110", "series": "LM241100-series", "type": "tapered_roller", "d_mm": 200.025, "D_mm": 276.225, "B_mm": 42.862, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 478, "static_load_kN": 780, "fatigue_load_limit_kN": 72, "max_rpm": 2000, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2000, "weight_g": 7700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF LM 241147/110 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 200.025 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.Reading the designation: LM241147 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the LM241100-series code identifies the dimensional series. The 200.025 mm bore, 276.225 mm OD and 42.862 mm width are the metric equivalents of the inch boundary dimensions. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Speed planning uses two different ceilings: 1,700 r/min thermal reference and 2,000 r/min mechanical limiting speed. Mounting practice for LM241147: the rotating cone takes the interference fit (m6 on a 200.025 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Material and manufacturing detail: the 7700 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the LM200 ISO envelope, with the pressed-steel cage contributing roughly 231 g of the total; the 200.025 mm bore is ground to IT5 roundness and the 276.225 mm OD to IT5 cylindricity, and the 42.862 mm width tolerance keeps the pair-setting scatter within the ISO preload class. The cup reference 110 is structural, not a suffix: it identifies the outer ring that, combined with the LM 241147 cone, produces the 200.025/276.225/42.862 mm envelope catalogue-listed as LM241147. Quote the cup number in full when ordering — the LM241100-series tables contain other cups that fit the same cone but change the bearing.", "applications": [ "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes", "large crusher and mineral-processing drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At 200.025 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The LM241100-series inch series at 200.025 mm bore (276.225×42.862 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the LM241147 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "At the 478 kN rating of LM241147, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 2,000 r/min speed end and heavier preload only where moment stiffness dominates.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 276.225 mm cup race release as noise within the first running hours.", "The 478/780 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM241147 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 241147/110 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of LM241147?", "a": "The SKF LM 241147/110 is a single-row tapered roller bearing with 200.025 mm bore, 276.225 mm outer diameter and 42.862 mm width (7.875 × 10.875 × 1.687 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 478 kN, C0 780 kN, fatigue load limit Pu 72 kN, reference speed 1,700 r/min, limiting speed 2,000 r/min, mass about 7700 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM241147 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM241100-series code marks the dimensional series. The metric dimensions 200.025×276.225×42.862 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM241147 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM241100-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM241147 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM241147 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM241147 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "LM241147-110", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM241147-110" ], "locale_variants": {} }, { "sku": "67983-67920", "brand": "SKF", "manufacturer_designation": "SKF 67983/67920", "series": "67900-series", "type": "tapered_roller", "d_mm": 203.2, "D_mm": 282.575, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 465, "static_load_kN": 830, "fatigue_load_limit_kN": 76.5, "max_rpm": 2000, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2000, "weight_g": 8850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Why the cup reference matters here: in the 67900-series tables the 67983 cone appears against several cup options. 67983 is the pairing with 67920, and that choice — not the cone — fixes the 282.575 mm OD, the raceway track position and the 46.038 mm assembled width.Ordering number SKF 67983/67920 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 203.2 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.Digit by digit, 67983 reads as cone reference / cup reference in the 67900-series inch series; the 203.2 mm bore, 282.575 mm OD and 46.038 mm width are the metric equivalents of the original inch boundary values. In SKF suffix language a bare 67983 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 1.78 (static 830 kN against dynamic 465 kN), typical of a tapered roller sized for axial capacity, and the 76.5 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. A single 67983 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Journal and housing interface: the 203.2 mm bore takes a m6 shaft seat (upper deviation ~0.406 mm for this diameter range) and the 282.575 mm outside diameter pairs with an H7 housing bore tolerance band of 282.575.000/282.595 mm; the 46.038 mm width defines the shoulder depth, and the 8850 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations.", "applications": [ "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes", "rolling-mill roll-neck bearings" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "At 203.2 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 67900-series inch series at 203.2 mm bore (282.575×46.038 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 67983 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 67983 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Shaft and housing fillets must clear the bearing chamfer so the 46.038 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 465/830 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 67983 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 67983/67920 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 67983 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 67983?", "a": "The SKF 67983/67920 is a single-row tapered roller bearing with 203.2 mm bore, 282.575 mm outer diameter and 46.038 mm width (8 × 11.125 × 1.813 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 465 kN, C0 830 kN, fatigue load limit Pu 76.5 kN, reference speed 1,600 r/min, limiting speed 2,000 r/min, mass about 8850 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 67983 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 67900-series code marks the dimensional series. The metric dimensions 203.2×282.575×46.038 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 67983 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (67900-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 67983 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "67983-67920", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "67983-67920" ], "locale_variants": {} }, { "sku": "LM241148-110", "brand": "SKF", "manufacturer_designation": "SKF LM 241148/110", "series": "LM241100-series", "type": "tapered_roller", "d_mm": 203.987, "D_mm": 276.225, "B_mm": 42.862, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 478, "static_load_kN": 780, "fatigue_load_limit_kN": 72, "max_rpm": 2000, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2000, "weight_g": 7200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " In SKF suffix language a bare LM241148 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 1.63 (static 780 kN against dynamic 478 kN), typical of a tapered roller sized for axial capacity, and the 72 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Because the contact line is tapered, one LM241148 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 203.987 mm shaft typically takes a m6 seat with an H7 housing bore. Operating context for the 203.987 mm bore: a shaft of this diameter in the xl-bore band typically runs between 163190 and 244784 r/min in real machinery, and the 276.225 mm outside diameter places the housing shoulder at 284 mm outer abutment; the 42.862 mm width and 7200 g mass together set the shaft critical speed and the housing resonance check for this LM200-series envelope. Housing and abutment design flows from the cup: in LM241148 the 110 cup fixes the 276.225 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the LM 241148 cone determines the 203.987 mm shaft interface; the 42.862 mm width is the assembled pair value.In SKF catalogue PUB BU/P1 17000, LM241148 appears as SKF LM 241148/110: an open, single-row tapered roller bearing in the LM241100-series, supplied with a pressed-steel cage as standard.In SKF inch-series tables LM241148 sits at 203.987 mm bore (8.031 in) with a 276.225 mm cup OD and 42.862 mm total width — dimensions that trace back to the original Timken boundary plan for the LM241100-series family.", "applications": [ "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "wind-turbine main shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At 203.987 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The LM241100-series inch series at 203.987 mm bore (276.225×42.862 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common LM241148 mounting error.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the LM241148 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The LM241148 shares its ISO 355 envelope with other tapered bearings of the same code but is not a drop-in replacement for a ball bearing: it cannot run effectively under pure radial load without a minimum axial load, and a deep-groove bearing cannot replace its combined-load duty.", "The 478/780 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM241148 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 241148/110 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in LM241148 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM241100-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM241148 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM241148 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM241148 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM241148?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 42.862 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM241148 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "LM241148-110", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM241148-110" ], "locale_variants": {} }, { "sku": "67985-67920", "brand": "SKF", "manufacturer_designation": "SKF 67985/67920", "series": "67900-series", "type": "tapered_roller", "d_mm": 206.375, "D_mm": 282.575, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 465, "static_load_kN": 830, "fatigue_load_limit_kN": 76.5, "max_rpm": 2000, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2000, "weight_g": 8450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Mounting practice for 67985: the rotating cone takes the interference fit (m6 on a 206.375 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Journal and housing interface: the 206.375 mm bore takes a m6 shaft seat (upper deviation ~0.413 mm for this diameter range) and the 282.575 mm outside diameter pairs with an H7 housing bore tolerance band of 282.575.000/282.595 mm; the 46.038 mm width defines the shoulder depth, and the 8450 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Within the 67900-series tables, 67985 appears in several rows because SKF lists multiple cup options for the same cone. 67985 is the 67920 variant, with 282.575 mm OD and 46.038 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.Ordering number SKF 67985/67920 in SKF catalogue PUB BU/P1 17000 denotes a single-row tapered roller bearing for a 206.375 mm shaft, inch series, with an open pressed-steel-cage execution and one-direction axial capacity.Numbering ties the bearing to its inch-series envelope: 67985 means a cone and cup matched pair in the 67900-series series — which is why the 206.375×282.575×46.038 mm outline swaps dimensionally with other inch-series bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Selection arithmetic: the C0/C ratio is about 1.78 (static 830 kN against dynamic 465 kN), typical of a tapered roller sized for axial capacity, and the 76.5 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation.", "applications": [ "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums", "large industrial mixer shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "At 206.375 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 67900-series inch series at 206.375 mm bore (282.575×46.038 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the 67985 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "At the 465 kN rating of 67985, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 2,000 r/min speed end and heavier preload only where moment stiffness dominates.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 465/830 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 67985 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 67985/67920 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does 67985 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 67985 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit 67985?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 46.038 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 67985 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 67985?", "a": "The SKF 67985/67920 is a single-row tapered roller bearing with 206.375 mm bore, 282.575 mm outer diameter and 46.038 mm width (8.125 × 11.125 × 1.813 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 465 kN, C0 830 kN, fatigue load limit Pu 76.5 kN, reference speed 1,600 r/min, limiting speed 2,000 r/min, mass about 8450 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 67985 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 67900-series code marks the dimensional series. The metric dimensions 206.375×282.575×46.038 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "67985-67920", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "67985-67920" ], "locale_variants": {} }, { "sku": "H242649-610", "brand": "SKF", "manufacturer_designation": "SKF H 242649/610", "series": "H242600-series", "type": "tapered_roller", "d_mm": 206.375, "D_mm": 336.55, "B_mm": 98.425, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1230, "static_load_kN": 2160, "fatigue_load_limit_kN": 190, "max_rpm": 1800, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1800, "weight_g": 34000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Dimensional interchange map: within the H2400 series at 206.375 mm bore, the 336.55 mm OD and 98.425 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 65.1 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 34000 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. A single-row inch tapered bearing is quoted as a cone/cup pair because the boundary dimensions belong to the combination, not to either half alone: in H242649 the H 242649 cone contributes the 206.375 mm bore and roller set, the 610 cup contributes the 336.55 mm OD raceway, and the assembled 98.425 mm width is the catalogue value.SKF H242649 (SKF H 242649/610) is the H242600-series tapered roller choice for a 206.375 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 336.55×98.425 mm envelope.In SKF inch-series tables H242649 sits at 206.375 mm bore (8.125 in) with a 336.55 mm cup OD and 98.425 mm total width — dimensions that trace back to the original Timken boundary plan for the H242600-series family. In SKF suffix language a bare H242649 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Selection arithmetic: the C0/C ratio is about 1.76 (static 2160 kN against dynamic 1230 kN), typical of a tapered roller sized for axial capacity, and the 190 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of H242649 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting.", "applications": [ "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "At 206.375 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The H242600-series inch series at 206.375 mm bore (336.55×98.425 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of H242649 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of H242649 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 336.55 mm cup race release as noise within the first running hours.", "The 1230/2160 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of H242649 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF H 242649/610 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit H242649?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 98.425 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is H242649 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of H242649?", "a": "The SKF H 242649/610 is a single-row tapered roller bearing with 206.375 mm bore, 336.55 mm outer diameter and 98.425 mm width (8.125 × 13.25 × 3.875 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1230 kN, C0 2160 kN, fatigue load limit Pu 190 kN, reference speed 1,300 r/min, limiting speed 1,800 r/min, mass about 34000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the H242649 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the H242600-series code marks the dimensional series. The metric dimensions 206.375×336.55×98.425 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in H242649 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (H242600-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "H242649-610", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "H242649-610" ], "locale_variants": {} }, { "sku": "LM742747-710", "brand": "SKF", "manufacturer_designation": "SKF LM 742747/710", "series": "LM742700-series", "type": "tapered_roller", "d_mm": 216.408, "D_mm": 285.75, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 466, "static_load_kN": 850, "fatigue_load_limit_kN": 76.5, "max_rpm": 2000, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2000, "weight_g": 7900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "LM742747 is a single-row tapered roller bearing in the LM742700-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.On the SKF nameplate, LM742747 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the LM742700-series marking the dimensional series. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 76.5 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.82 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. A single LM742747 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Material and manufacturing detail: the 7900 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the LM700 ISO envelope, with the pressed-steel cage contributing roughly 237 g of the total; the 216.408 mm bore is ground to IT5 roundness and the 285.75 mm OD to IT5 cylindricity, and the 46.038 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Cup-side note for 710: the outer ring's rib profile and the 285.75 mm outside diameter are cup-specific within the LM742700-series tables, so substituting a different cup against the same LM 742747 cone changes both the assembled 46.038 mm width and the axial free-play setting of the mounted pair.", "applications": [ "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "offshore winch and drawworks drums" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "At 216.408 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The LM742700-series inch series at 216.408 mm bore (285.75×46.038 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of LM742747 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Setting is a design value, not an assembly feel: excessive preload in the LM742747 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Shaft and housing fillets must clear the bearing chamfer so the 46.038 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 466/850 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM742747 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 742747/710 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of LM742747?", "a": "The SKF LM 742747/710 is a single-row tapered roller bearing with 216.408 mm bore, 285.75 mm outer diameter and 46.038 mm width (8.52 × 11.25 × 1.813 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 466 kN, C0 850 kN, fatigue load limit Pu 76.5 kN, reference speed 1,600 r/min, limiting speed 2,000 r/min, mass about 7900 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM742747 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM742700-series code marks the dimensional series. The metric dimensions 216.408×285.75×46.038 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM742747 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM742700-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM742747 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM742747 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM742747 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "LM742747-710", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM742747-710" ], "locale_variants": {} }, { "sku": "M244249A-210", "brand": "SKF", "manufacturer_designation": "SKF M 244249 A/210", "series": "M244200-series", "type": "tapered_roller", "d_mm": 220.662, "D_mm": 314.325, "B_mm": 61.912, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 784, "static_load_kN": 1320, "fatigue_load_limit_kN": 118, "max_rpm": 1800, "reference_speed_rpm": 1500, "limiting_speed_rpm": 1800, "weight_g": 15000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF inch-series tables M244249A sits at 220.662 mm bore (8.687 in) with a 314.325 mm cup OD and 61.912 mm total width — dimensions that trace back to the original Timken boundary plan for the M244200-series family. In SKF suffix language a bare M244249A is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 1,500 r/min reference speed the 46.8 mm-section M244249A is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 1,800 r/min as the mechanical ceiling. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of M244249A must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Material and manufacturing detail: the 15000 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the M2400 ISO envelope, with the pressed-steel cage contributing roughly 450 g of the total; the 220.662 mm bore is ground to IT5 roundness and the 314.325 mm OD to IT5 cylindricity, and the 61.912 mm width tolerance keeps the pair-setting scatter within the ISO preload class. The cup reference 210 is structural, not a suffix: it identifies the outer ring that, combined with the M 244249 A cone, produces the 220.662/314.325/61.912 mm envelope catalogue-listed as M244249A. Quote the cup number in full when ordering — the M244200-series tables contain other cups that fit the same cone but change the bearing.SKF M 244249 A/210 belongs to the SKF single-row tapered roller range — the 220.662 mm bore entry in the inch M244200-series, dimensioned 314.325 mm OD and 61.912 mm wide.", "applications": [ "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "At 220.662 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The M244200-series inch series at 220.662 mm bore (314.325×61.912 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single M244249A cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "At the 784 kN rating of M244249A, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 1,800 r/min speed end and heavier preload only where moment stiffness dominates.", "Open M244249A units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 784/1320 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of M244249A (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF M 244249 A/210 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the M244249A inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the M244200-series code marks the dimensional series. The metric dimensions 220.662×314.325×61.912 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in M244249A mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (M244200-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single M244249A take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does M244249A compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load M244249A position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit M244249A?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 61.912 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "M244249A-210", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "M244249A-210" ], "locale_variants": {} }, { "sku": "LM245846-810", "brand": "SKF", "manufacturer_designation": "SKF LM 245846/810", "series": "LM245800-series", "type": "tapered_roller", "d_mm": 230.188, "D_mm": 317.5, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 556, "static_load_kN": 980, "fatigue_load_limit_kN": 90, "max_rpm": 1800, "reference_speed_rpm": 1500, "limiting_speed_rpm": 1800, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Journal and housing interface: the 230.188 mm bore takes a m6 shaft seat (upper deviation ~0.460 mm for this diameter range) and the 317.5 mm outside diameter pairs with an H7 housing bore tolerance band of 317.5.000/317.520 mm; the 47.625 mm width defines the shoulder depth, and the 11000 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Cup-side note for 810: the outer ring's rib profile and the 317.5 mm outside diameter are cup-specific within the LM245800-series tables, so substituting a different cup against the same LM 245846 cone changes both the assembled 47.625 mm width and the axial free-play setting of the mounted pair.For a 230.188 mm shaft carrying combined load, SKF lists LM245846 under catalogue execution SKF LM 245846/810: one open single-row tapered roller bearing in the inch LM245800-series.Numbering ties the bearing to its inch-series envelope: LM245846 means a cone and cup matched pair in the LM245800-series series — which is why the 230.188×317.5×47.625 mm outline swaps dimensionally with other inch-series bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. Speed planning uses two different ceilings: 1,500 r/min thermal reference and 1,800 r/min mechanical limiting speed. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of LM245846 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting.", "applications": [ "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "At 230.188 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The LM245800-series inch series at 230.188 mm bore (317.5×47.625 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one LM245846 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the LM245846 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The 11000 g mass and 47.625 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of LM245846.", "The 556/980 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM245846 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 245846/810 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit LM245846?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 47.625 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM245846 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM245846?", "a": "The SKF LM 245846/810 is a single-row tapered roller bearing with 230.188 mm bore, 317.5 mm outer diameter and 47.625 mm width (9.063 × 12.5 × 1.875 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 556 kN, C0 980 kN, fatigue load limit Pu 90 kN, reference speed 1,500 r/min, limiting speed 1,800 r/min, mass about 11000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM245846 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM245800-series code marks the dimensional series. The metric dimensions 230.188×317.5×47.625 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM245846 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM245800-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "LM245846-810", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM245846-810" ], "locale_variants": {} }, { "sku": "544091-544118", "brand": "SKF", "manufacturer_designation": "SKF 544091/544118", "series": "544000-series", "type": "tapered_roller", "d_mm": 231.775, "D_mm": 300.038, "B_mm": 33.338, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 267, "static_load_kN": 425, "fatigue_load_limit_kN": 39, "max_rpm": 1900, "reference_speed_rpm": 1500, "limiting_speed_rpm": 1900, "weight_g": 5200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Journal and housing interface: the 231.775 mm bore takes a m6 shaft seat (upper deviation ~0.464 mm for this diameter range) and the 300.038 mm outside diameter pairs with an H7 housing bore tolerance band of 300.038.000/300.058 mm; the 33.338 mm width defines the shoulder depth, and the 5200 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. The cup reference 544118 is structural, not a suffix: it identifies the outer ring that, combined with the 544091 cone, produces the 231.775/300.038/33.338 mm envelope catalogue-listed as 544091. Quote the cup number in full when ordering — the 544000-series tables contain other cups that fit the same cone but change the bearing.The SKF 544091/544118 is a 231.775×300.038×33.338 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.Numbering ties the bearing to its inch-series envelope: 544091 means a cone and cup matched pair in the 544000-series series — which is why the 231.775×300.038×33.338 mm outline swaps dimensionally with other inch-series bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 34.1 mm radial section height ((300.038−231.775)/2) and 5200 g catalogue mass frame a 231.775 mm bore bearing rated at 267 kN C — roughly 1.15 kN of dynamic capacity per millimetre of bore before application factors. A single 544091 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel.", "applications": [ "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "At 231.775 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 544000-series inch series at 231.775 mm bore (300.038×33.338 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one 544091 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Do not mix brands or executions inside one 544091 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Catalogue reference speed and limiting speed are different limits: the 1,500 r/min reference is a thermal criterion under load, while the 1,900 r/min limiting value is the mechanical ceiling — observe both.", "The 267/425 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 544091 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 544091/544118 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit 544091?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 33.338 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is 544091 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 544091?", "a": "The SKF 544091/544118 is a single-row tapered roller bearing with 231.775 mm bore, 300.038 mm outer diameter and 33.338 mm width (9.125 × 11.813 × 1.313 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 267 kN, C0 425 kN, fatigue load limit Pu 39 kN, reference speed 1,500 r/min, limiting speed 1,900 r/min, mass about 5200 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 544091 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 544000-series code marks the dimensional series. The metric dimensions 231.775×300.038×33.338 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 544091 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (544000-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "544091-544118", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "544091-544118" ], "locale_variants": {} }, { "sku": "LM245848-810", "brand": "SKF", "manufacturer_designation": "SKF LM 245848/810", "series": "LM245800-series", "type": "tapered_roller", "d_mm": 231.775, "D_mm": 317.5, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 556, "static_load_kN": 980, "fatigue_load_limit_kN": 90, "max_rpm": 1800, "reference_speed_rpm": 1500, "limiting_speed_rpm": 1800, "weight_g": 10500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " In SKF suffix language a bare LM245848 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 1,500 r/min reference speed the 42.9 mm-section LM245848 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 1,800 r/min as the mechanical ceiling. For a 231.775 mm shaft the usual cone seat is m6 with an H7 housing when the inner ring rotates; arrange two LM245848 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Operating context for the 231.775 mm bore: a shaft of this diameter in the xl-bore band typically runs between 185420 and 278130 r/min in real machinery, and the 317.5 mm outside diameter places the housing shoulder at 326 mm outer abutment; the 47.625 mm width and 10500 g mass together set the shaft critical speed and the housing resonance check for this LM200-series envelope. Two catalogue entries share the LM 245848 cone but use different cups; this one, LM245848, takes the 810 cup and is ground for the resulting 317.5 mm OD / 47.625 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.SKF LM 245848/810 belongs to the SKF single-row tapered roller range — the 231.775 mm bore entry in the inch LM245800-series, dimensioned 317.5 mm OD and 47.625 mm wide.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (LM245800-series) ties the pair to a specific boundary plan. Dimensions 231.775×317.5×47.625 mm are the converted metric envelope.", "applications": [ "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "large crusher and mineral-processing drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "At 231.775 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The LM245800-series inch series at 231.775 mm bore (317.5×47.625 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 556 kN rating of LM245848, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 1,800 r/min speed end and heavier preload only where moment stiffness dominates.", "Setting is a design value, not an assembly feel: excessive preload in the LM245848 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 317.5 mm cup race release as noise within the first running hours.", "The 556/980 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM245848 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 245848/810 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in LM245848 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM245800-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM245848 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM245848 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM245848 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM245848?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 47.625 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM245848 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "LM245848-810", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM245848-810" ], "locale_variants": {} }, { "sku": "LM545848-810", "brand": "SKF", "manufacturer_designation": "SKF LM 545848/810", "series": "LM545800-series", "type": "tapered_roller", "d_mm": 234.848, "D_mm": 314.325, "B_mm": 49.212, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 608, "static_load_kN": 1000, "fatigue_load_limit_kN": 91.5, "max_rpm": 1800, "reference_speed_rpm": 1500, "limiting_speed_rpm": 1800, "weight_g": 10500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " With C 608 kN and C0 1000 kN, the LM545848 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 1,800 r/min. Because the contact line is tapered, one LM545848 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 234.848 mm shaft typically takes a m6 seat with an H7 housing bore. Load system: the 608 kN basic dynamic rating C and 1000 kN static rating C0 give a C0/C balance of 1.64, and dividing C by the 234.848 mm bore yields 2.59 kN per millimetre of journal — a density metric that compares across families; the 91.5 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 234.848 mm shaft carrying variable duty. Two catalogue entries share the LM 545848 cone but use different cups; this one, LM545848, takes the 810 cup and is ground for the resulting 314.325 mm OD / 49.212 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.In SKF catalogue PUB BU/P1 17000, LM545848 appears as SKF LM 545848/810: an open, single-row tapered roller bearing in the LM545800-series, supplied with a pressed-steel cage as standard.In SKF inch-series tables LM545848 sits at 234.848 mm bore (9.246 in) with a 314.325 mm cup OD and 49.212 mm total width — dimensions that trace back to the original Timken boundary plan for the LM545800-series family. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "rolling-mill roll-neck bearings" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At 234.848 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The LM545800-series inch series at 234.848 mm bore (314.325×49.212 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 608 kN rating of LM545848, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 1,800 r/min speed end and heavier preload only where moment stiffness dominates.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the LM545848 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 608/1000 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM545848 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 545848/810 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single LM545848 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM545848 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM545848 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM545848?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 49.212 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM545848 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM545848?", "a": "The SKF LM 545848/810 is a single-row tapered roller bearing with 234.848 mm bore, 314.325 mm outer diameter and 49.212 mm width (9.246 × 12.375 × 1.937 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 608 kN, C0 1000 kN, fatigue load limit Pu 91.5 kN, reference speed 1,500 r/min, limiting speed 1,800 r/min, mass about 10500 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "LM545848-810", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM545848-810" ], "locale_variants": {} }, { "sku": "M349547-510", "brand": "SKF", "manufacturer_designation": "SKF M 349547/510", "series": "M349500-series", "type": "tapered_roller", "d_mm": 255.6, "D_mm": 342.9, "B_mm": 57.15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 698, "static_load_kN": 1400, "fatigue_load_limit_kN": 125, "max_rpm": 1600, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1600, "weight_g": 15000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Specify pairs rather than single units wherever thrust reverses: the tapered contact of M349547 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Load system: the 698 kN basic dynamic rating C and 1400 kN static rating C0 give a C0/C balance of 2.01, and dividing C by the 255.6 mm bore yields 2.73 kN per millimetre of journal — a density metric that compares across families; the 125 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 255.6 mm shaft carrying variable duty. Housing and abutment design flows from the cup: in M349547 the 510 cup fixes the 342.9 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the M 349547 cone determines the 255.6 mm shaft interface; the 57.15 mm width is the assembled pair value.The SKF M 349547/510 is a 255.6×342.9×57.15 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (M349500-series) ties the pair to a specific boundary plan. Dimensions 255.6×342.9×57.15 mm are the converted metric envelope. In SKF suffix language a bare M349547 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. At 1,300 r/min reference speed the 43.6 mm-section M349547 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 1,600 r/min as the mechanical ceiling.", "applications": [ "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts", "marine propulsion gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "At 255.6 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The M349500-series inch series at 255.6 mm bore (342.9×57.15 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of M349547 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common M349547 mounting error.", "The 15000 g mass and 57.15 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of M349547.", "The 698/1400 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of M349547 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF M 349547/510 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does M349547 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load M349547 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit M349547?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 57.15 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is M349547 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of M349547?", "a": "The SKF M 349547/510 is a single-row tapered roller bearing with 255.6 mm bore, 342.9 mm outer diameter and 57.15 mm width (10.063 × 13.5 × 2.25 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 698 kN, C0 1400 kN, fatigue load limit Pu 125 kN, reference speed 1,300 r/min, limiting speed 1,600 r/min, mass about 15000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the M349547 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the M349500-series code marks the dimensional series. The metric dimensions 255.6×342.9×57.15 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "M349547-510", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "M349547-510" ], "locale_variants": {} }, { "sku": "M349549-510", "brand": "SKF", "manufacturer_designation": "SKF M 349549/510", "series": "M349500-series", "type": "tapered_roller", "d_mm": 257.175, "D_mm": 342.9, "B_mm": 57.15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 698, "static_load_kN": 1400, "fatigue_load_limit_kN": 125, "max_rpm": 1600, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1600, "weight_g": 14000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF inch-series tables M349549 sits at 257.175 mm bore (10.125 in) with a 342.9 mm cup OD and 57.15 mm total width — dimensions that trace back to the original Timken boundary plan for the M349500-series family. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Catalogue mass 14000 g for the 257.175×342.9×57.15 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. Mounting practice for M349549: the rotating cone takes the interference fit (m6 on a 257.175 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Cross-section geometry: the 42.9 mm half-section ((342.9−257.175)/2) of this M3400-series unit places the roller large-end pitch diameter at roughly 300 mm, and the 57.15 mm axial width is split between cone (31 mm) and cup rib (26 mm) — a geometry that sets the contact angle and, with the 14000 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Cone-and-cup identity in M349549: the leading M 349549 reference identifies the inner ring, rollers and cage; the trailing 510 reference identifies the outer ring. The M349500-series series lists alternative cups for the same cone, each producing a different 342.9 mm OD or 57.15 mm width — hence a different SKU even though the bore stays at 257.175 mm.M349549 is a single-row tapered roller bearing in the M349500-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.", "applications": [ "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums", "offshore winch and drawworks drums" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "At 257.175 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The M349500-series inch series at 257.175 mm bore (342.9×57.15 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "A single M349549 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the M349549 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 342.9 mm cup race release as noise within the first running hours.", "The 698/1400 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of M349549 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF M 349549/510 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the M349549 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the M349500-series code marks the dimensional series. The metric dimensions 257.175×342.9×57.15 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in M349549 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (M349500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single M349549 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does M349549 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load M349549 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit M349549?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 57.15 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "M349549-510", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "M349549-510" ], "locale_variants": {} }, { "sku": "M249747-710", "brand": "SKF", "manufacturer_designation": "SKF M 249747/710", "series": "M249700-series", "type": "tapered_roller", "d_mm": 257.175, "D_mm": 358.775, "B_mm": 71.438, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1030, "static_load_kN": 1760, "fatigue_load_limit_kN": 156, "max_rpm": 1600, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1600, "weight_g": 21500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 1030 kN and C0 1760 kN, the M249747 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 1,600 r/min. A single M249747 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Cross-section geometry: the 50.8 mm half-section ((358.775−257.175)/2) of this M2400-series unit places the roller large-end pitch diameter at roughly 307 mm, and the 71.438 mm axial width is split between cone (39 mm) and cup rib (32 mm) — a geometry that sets the contact angle and, with the 21500 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Housing and abutment design flows from the cup: in M249747 the 710 cup fixes the 358.775 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the M 249747 cone determines the 257.175 mm shaft interface; the 71.438 mm width is the assembled pair value.SKF M 249747/710 belongs to the SKF single-row tapered roller range — the 257.175 mm bore entry in the inch M249700-series, dimensioned 358.775 mm OD and 71.438 mm wide.Numbering ties the bearing to its inch-series envelope: M249747 means a cone and cup matched pair in the M249700-series series — which is why the 257.175×358.775×71.438 mm outline swaps dimensionally with other inch-series bearings of the same code.", "applications": [ "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes", "offshore winch and drawworks drums" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "At 257.175 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The M249700-series inch series at 257.175 mm bore (358.775×71.438 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the M249747 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common M249747 mounting error.", "The 21500 g mass and 71.438 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of M249747.", "The 1030/1760 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of M249747 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF M 249747/710 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in M249747 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (M249700-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single M249747 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does M249747 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load M249747 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit M249747?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 71.438 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is M249747 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "M249747-710", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "M249747-710" ], "locale_variants": {} }, { "sku": "38880-38820", "brand": "SKF", "manufacturer_designation": "SKF 38880/38820", "series": "38800-series", "type": "tapered_roller", "d_mm": 263.525, "D_mm": 325.438, "B_mm": 28.575, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 273, "static_load_kN": 550, "fatigue_load_limit_kN": 48, "max_rpm": 1700, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1700, "weight_g": 5300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Why the cup reference matters here: in the 38800-series tables the 38880 cone appears against several cup options. 38880 is the pairing with 38820, and that choice — not the cone — fixes the 325.438 mm OD, the raceway track position and the 28.575 mm assembled width.SKF 38880 (SKF 38880/38820) is the 38800-series tapered roller choice for a 263.525 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 325.438×28.575 mm envelope.The 38800-series series assigns 263.525 mm bore, 325.438 mm OD and 28.575 mm width to 38880; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. In SKF suffix language a bare 38880 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. With C 273 kN and C0 550 kN, the 38880 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 1,700 r/min. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 38880 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Journal and housing interface: the 263.525 mm bore takes a m6 shaft seat (upper deviation ~0.527 mm for this diameter range) and the 325.438 mm outside diameter pairs with an H7 housing bore tolerance band of 325.438.000/325.458 mm; the 28.575 mm width defines the shoulder depth, and the 5300 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations.", "applications": [ "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "wind-turbine main shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "At 263.525 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The 320 series at 263.525 mm bore (325.438×28.575 mm) is the low-friction, higher-speed section; it carries less thrust than a 302 of the same bore, so verify the axial load share before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 38880 mounting error.", "Setting is a design value, not an assembly feel: excessive preload in the 38880 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Catalogue reference speed and limiting speed are different limits: the 1,400 r/min reference is a thermal criterion under load, while the 1,700 r/min limiting value is the mechanical ceiling — observe both.", "The 273/550 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of 38880 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 38880/38820 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is 38880 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of 38880?", "a": "The SKF 38880/38820 is a single-row tapered roller bearing with 263.525 mm bore, 325.438 mm outer diameter and 28.575 mm width (10.375 × 12.813 × 1.125 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 273 kN, C0 550 kN, fatigue load limit Pu 48 kN, reference speed 1,400 r/min, limiting speed 1,700 r/min, mass about 5300 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the 38880 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the 38800-series code marks the dimensional series. The metric dimensions 263.525×325.438×28.575 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in 38880 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (38800-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single 38880 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "38880-38820", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "38880-38820" ], "locale_variants": {} }, { "sku": "LM451345-310", "brand": "SKF", "manufacturer_designation": "SKF LM 451345/310", "series": "LM451300-series", "type": "tapered_roller", "d_mm": 263.525, "D_mm": 355.6, "B_mm": 57.15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 789, "static_load_kN": 1400, "fatigue_load_limit_kN": 122, "max_rpm": 1600, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1600, "weight_g": 16000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. At 1,300 r/min reference speed the 46.0 mm-section LM451345 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 1,600 r/min as the mechanical ceiling. For a 263.525 mm shaft the usual cone seat is m6 with an H7 housing when the inner ring rotates; arrange two LM451345 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Material and manufacturing detail: the 16000 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the LM400 ISO envelope, with the pressed-steel cage contributing roughly 480 g of the total; the 263.525 mm bore is ground to IT5 roundness and the 355.6 mm OD to IT5 cylindricity, and the 57.15 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Cone-and-cup identity in LM451345: the leading LM 451345 reference identifies the inner ring, rollers and cage; the trailing 310 reference identifies the outer ring. The LM451300-series series lists alternative cups for the same cone, each producing a different 355.6 mm OD or 57.15 mm width — hence a different SKU even though the bore stays at 263.525 mm.For a 263.525 mm shaft carrying combined load, SKF lists LM451345 under catalogue execution SKF LM 451345/310: one open single-row tapered roller bearing in the inch LM451300-series.Reading the designation: LM451345 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the LM451300-series code identifies the dimensional series. The 263.525 mm bore, 355.6 mm OD and 57.15 mm width are the metric equivalents of the inch boundary dimensions.", "applications": [ "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "large crusher and mineral-processing drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "At 263.525 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The LM451300-series inch series at 263.525 mm bore (355.6×57.15 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the LM451345 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Do not mix brands or executions inside one LM451345 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "Catalogue reference speed and limiting speed are different limits: the 1,300 r/min reference is a thermal criterion under load, while the 1,600 r/min limiting value is the mechanical ceiling — observe both.", "The 789/1400 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM451345 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 451345/310 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What do the cone and cup numbers in LM451345 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM451300-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM451345 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM451345 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM451345 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM451345?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 57.15 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM451345 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." } ], "cross_ref": [ { "equiv_sku": "LM451345-310", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM451345-310" ], "locale_variants": {} }, { "sku": "L555249-210", "brand": "SKF", "manufacturer_designation": "SKF L 555249/210", "series": "L555200-series", "type": "tapered_roller", "d_mm": 292.1, "D_mm": 374.65, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 539, "static_load_kN": 1140, "fatigue_load_limit_kN": 98, "max_rpm": 1500, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1500, "weight_g": 12500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " For a 292.1 mm shaft the usual cone seat is m6 with an H7 housing when the inner ring rotates; arrange two L555249 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Dimensional interchange map: within the L5500 series at 292.1 mm bore, the 374.65 mm OD and 47.625 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 41.3 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 12500 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Two catalogue entries share the L 555249 cone but use different cups; this one, L555249, takes the 210 cup and is ground for the resulting 374.65 mm OD / 47.625 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.SKF L 555249/210 belongs to the SKF single-row tapered roller range — the 292.1 mm bore entry in the inch L555200-series, dimensioned 374.65 mm OD and 47.625 mm wide.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (L555200-series) ties the pair to a specific boundary plan. Dimensions 292.1×374.65×47.625 mm are the converted metric envelope. In SKF suffix language a bare L555249 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 98 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 2.12 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running.", "applications": [ "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes", "wind-turbine main shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "At 292.1 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The L555200-series inch series at 292.1 mm bore (374.65×47.625 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of L555249 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Setting is a design value, not an assembly feel: excessive preload in the L555249 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Shaft and housing fillets must clear the bearing chamfer so the 47.625 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.", "The 539/1140 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of L555249 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF L 555249/210 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does L555249 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load L555249 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit L555249?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 47.625 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is L555249 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of L555249?", "a": "The SKF L 555249/210 is a single-row tapered roller bearing with 292.1 mm bore, 374.65 mm outer diameter and 47.625 mm width (11.5 × 14.75 × 1.875 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 539 kN, C0 1140 kN, fatigue load limit Pu 98 kN, reference speed 1,200 r/min, limiting speed 1,500 r/min, mass about 12500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the L555249 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the L555200-series code marks the dimensional series. The metric dimensions 292.1×374.65×47.625 mm are the converted equivalents of the original inch boundary dimensions." } ], "cross_ref": [ { "equiv_sku": "L555249-210", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "L555249-210" ], "locale_variants": {} }, { "sku": "L357049-010", "brand": "SKF", "manufacturer_designation": "SKF L 357049/010", "series": "L357000-series", "type": "tapered_roller", "d_mm": 304.8, "D_mm": 393.7, "B_mm": 50.8, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 655, "static_load_kN": 1220, "fatigue_load_limit_kN": 104, "max_rpm": 1400, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1400, "weight_g": 15000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Selection arithmetic: the C0/C ratio is about 1.86 (static 1220 kN against dynamic 655 kN), typical of a tapered roller sized for axial capacity, and the 104 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Specify pairs rather than single units wherever thrust reverses: the tapered contact of L357049 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Operating context for the 304.8 mm bore: a shaft of this diameter in the xl-bore band typically runs between 243840 and 365760 r/min in real machinery, and the 393.7 mm outside diameter places the housing shoulder at 402 mm outer abutment; the 50.8 mm width and 15000 g mass together set the shaft critical speed and the housing resonance check for this L3500-series envelope. The cup reference 010 is structural, not a suffix: it identifies the outer ring that, combined with the L 357049 cone, produces the 304.8/393.7/50.8 mm envelope catalogue-listed as L357049. Quote the cup number in full when ordering — the L357000-series tables contain other cups that fit the same cone but change the bearing.The SKF L 357049/010 is a 304.8×393.7×50.8 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.In SKF inch-series tables L357049 sits at 304.8 mm bore (12 in) with a 393.7 mm cup OD and 50.8 mm total width — dimensions that trace back to the original Timken boundary plan for the L357000-series family. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers.", "applications": [ "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "marine propulsion gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "At 304.8 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The L357000-series inch series at 304.8 mm bore (393.7×50.8 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 655 kN rating of L357049, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 1,400 r/min speed end and heavier preload only where moment stiffness dominates.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common L357049 mounting error.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 393.7 mm cup race release as noise within the first running hours.", "The 655/1220 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of L357049 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF L 357049/010 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single L357049 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does L357049 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load L357049 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit L357049?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 50.8 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is L357049 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of L357049?", "a": "The SKF L 357049/010 is a single-row tapered roller bearing with 304.8 mm bore, 393.7 mm outer diameter and 50.8 mm width (12 × 15.5 × 2 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 655 kN, C0 1220 kN, fatigue load limit Pu 104 kN, reference speed 1,100 r/min, limiting speed 1,400 r/min, mass about 15000 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "L357049-010", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "L357049-010" ], "locale_variants": {} }, { "sku": "LM757049-010", "brand": "SKF", "manufacturer_designation": "SKF LM 757049/010", "series": "LM757000-series", "type": "tapered_roller", "d_mm": 304.8, "D_mm": 406.4, "B_mm": 63.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 775, "static_load_kN": 1700, "fatigue_load_limit_kN": 143, "max_rpm": 1300, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1300, "weight_g": 22500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The 143 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 2.19 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Because the contact line is tapered, one LM757049 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 304.8 mm shaft typically takes a m6 seat with an H7 housing bore. Material and manufacturing detail: the 22500 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the LM700 ISO envelope, with the pressed-steel cage contributing roughly 675 g of the total; the 304.8 mm bore is ground to IT5 roundness and the 406.4 mm OD to IT5 cylindricity, and the 63.5 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Two catalogue entries share the LM 757049 cone but use different cups; this one, LM757049, takes the 010 cup and is ground for the resulting 406.4 mm OD / 63.5 mm width envelope. Selecting a sibling cup produces a different boundary plan and a different order number, so the full designation is required at purchase.The SKF LM 757049/010 is a 304.8×406.4×63.5 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.In SKF inch-series tables LM757049 sits at 304.8 mm bore (12 in) with a 406.4 mm cup OD and 63.5 mm total width — dimensions that trace back to the original Timken boundary plan for the LM757000-series family. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number.", "applications": [ "wind-turbine main shafts", "marine propulsion gearboxes", "large industrial mixer shafts", "large crusher and mineral-processing drives" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At 304.8 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The LM757000-series inch series at 304.8 mm bore (406.4×63.5 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 775 kN rating of LM757049, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 1,300 r/min speed end and heavier preload only where moment stiffness dominates.", "At the 775 kN rating of LM757049, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 1,300 r/min speed end and heavier preload only where moment stiffness dominates.", "Open LM757049 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.", "The 775/1700 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM757049 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 757049/010 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single LM757049 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM757049 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM757049 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM757049?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 63.5 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM757049 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM757049?", "a": "The SKF LM 757049/010 is a single-row tapered roller bearing with 304.8 mm bore, 406.4 mm outer diameter and 63.5 mm width (12 × 16 × 2.5 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 775 kN, C0 1700 kN, fatigue load limit Pu 143 kN, reference speed 1,100 r/min, limiting speed 1,300 r/min, mass about 22500 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "LM757049-010", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM757049-010" ], "locale_variants": {} }, { "sku": "HM259048-010-HA4", "brand": "SKF", "manufacturer_designation": "SKF HM 259048/010/HA4", "series": "HM259000-series", "type": "tapered_roller", "d_mm": 317.5, "D_mm": 447.675, "B_mm": 85.725, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1363, "static_load_kN": 2700, "fatigue_load_limit_kN": 220, "max_rpm": 1200, "reference_speed_rpm": 900, "limiting_speed_rpm": 1200, "weight_g": 41000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Operating context for the 317.5 mm bore: a shaft of this diameter in the xl-bore band typically runs between 254000 and 381000 r/min in real machinery, and the 447.675 mm outside diameter places the housing shoulder at 456 mm outer abutment; the 85.725 mm width and 41000 g mass together set the shaft critical speed and the housing resonance check for this HM200-series envelope. Cone-and-cup identity in HM259048: the leading HM 259048 reference identifies the inner ring, rollers and cage; the trailing 010/HA4 reference identifies the outer ring. The HM259000-series series lists alternative cups for the same cone, each producing a different 447.675 mm OD or 85.725 mm width — hence a different SKU even though the bore stays at 317.5 mm.The SKF HM 259048/010/HA4 is a 317.5×447.675×85.725 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.In SKF inch-series tables HM259048 sits at 317.5 mm bore (12.5 in) with a 447.675 mm cup OD and 85.725 mm total width — dimensions that trace back to the original Timken boundary plan for the HM259000-series family. In SKF suffix language a bare HM259048 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 220 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.98 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Fit selection follows the rotating ring — interference on a rotating cone — and two HM259048 units are required to take reversing thrust; keep the induced axial load inside the rated capacity when calculating the pair.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "marine propulsion gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "At 317.5 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The HM259000-series inch series at 317.5 mm bore (447.675×85.725 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HM259048 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Setting is a design value, not an assembly feel: excessive preload in the HM259048 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "The 41000 g mass and 85.725 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of HM259048.", "The 1363/2700 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM259048 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 259048/010/HA4 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit HM259048?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 85.725 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HM259048 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM259048?", "a": "The SKF HM 259048/010/HA4 is a single-row tapered roller bearing with 317.5 mm bore, 447.675 mm outer diameter and 85.725 mm width (12.5 × 17.625 × 3.375 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1363 kN, C0 2700 kN, fatigue load limit Pu 220 kN, reference speed 900 r/min, limiting speed 1,200 r/min, mass about 41000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM259048 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM259000-series code marks the dimensional series. The metric dimensions 317.5×447.675×85.725 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM259048 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM259000-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "HM259048-010-HA4", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM259048-010-HA4" ], "locale_variants": {} }, { "sku": "HM261049-010", "brand": "SKF", "manufacturer_designation": "SKF HM 261049/010", "series": "HM261000-series", "type": "tapered_roller", "d_mm": 333.375, "D_mm": 469.9, "B_mm": 90.488, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1428, "static_load_kN": 2850, "fatigue_load_limit_kN": 232, "max_rpm": 1200, "reference_speed_rpm": 850, "limiting_speed_rpm": 1200, "weight_g": 47000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Cross-section geometry: the 68.3 mm half-section ((469.9−333.375)/2) of this HM200-series unit places the roller large-end pitch diameter at roughly 401 mm, and the 90.488 mm axial width is split between cone (50 mm) and cup rib (41 mm) — a geometry that sets the contact angle and, with the 47000 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Housing and abutment design flows from the cup: in HM261049 the 010 cup fixes the 469.9 mm OD, the outer-ring face position and the rib shoulder that the rollers contact under thrust, while the HM 261049 cone determines the 333.375 mm shaft interface; the 90.488 mm width is the assembled pair value.SKF HM261049 (SKF HM 261049/010) is the HM261000-series tapered roller choice for a 333.375 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 469.9×90.488 mm envelope.On the SKF nameplate, HM261049 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the HM261000-series marking the dimensional series. In SKF suffix language a bare HM261049 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Speed planning uses two different ceilings: 850 r/min thermal reference and 1,200 r/min mechanical limiting speed. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of HM261049 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting.", "applications": [ "marine propulsion gearboxes", "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "At 333.375 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The HM261000-series inch series at 333.375 mm bore (469.9×90.488 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 1428 kN rating of HM261049, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 1,200 r/min speed end and heavier preload only where moment stiffness dominates.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HM261049 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 469.9 mm cup race release as noise within the first running hours.", "The 1428/2850 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM261049 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 261049/010 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What shaft and housing fits suit HM261049?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 90.488 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is HM261049 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of HM261049?", "a": "The SKF HM 261049/010 is a single-row tapered roller bearing with 333.375 mm bore, 469.9 mm outer diameter and 90.488 mm width (13.125 × 18.5 × 3.563 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1428 kN, C0 2850 kN, fatigue load limit Pu 232 kN, reference speed 850 r/min, limiting speed 1,200 r/min, mass about 47000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM261049 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM261000-series code marks the dimensional series. The metric dimensions 333.375×469.9×90.488 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM261049 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM261000-series) groups sizes that share the same boundary-dimension plan." } ], "cross_ref": [ { "equiv_sku": "HM261049-010", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM261049-010" ], "locale_variants": {} }, { "sku": "LM361649-610", "brand": "SKF", "manufacturer_designation": "SKF LM 361649/610", "series": "LM361600-series", "type": "tapered_roller", "d_mm": 342.9, "D_mm": 450.85, "B_mm": 66.675, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1000, "static_load_kN": 2200, "fatigue_load_limit_kN": 180, "max_rpm": 1200, "reference_speed_rpm": 900, "limiting_speed_rpm": 1200, "weight_g": 28000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " With C 1000 kN and C0 2200 kN, the LM361649 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 1,200 r/min. Specify pairs rather than single units wherever thrust reverses: the tapered contact of LM361649 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Operating context for the 342.9 mm bore: a shaft of this diameter in the xl-bore band typically runs between 274320 and 411480 r/min in real machinery, and the 450.85 mm outside diameter places the housing shoulder at 459 mm outer abutment; the 66.675 mm width and 28000 g mass together set the shaft critical speed and the housing resonance check for this LM300-series envelope. Within the LM361600-series tables, LM 361649 appears in several rows because SKF lists multiple cup options for the same cone. LM361649 is the 610 variant, with 450.85 mm OD and 66.675 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.In SKF catalogue PUB BU/P1 17000, LM361649 appears as SKF LM 361649/610: an open, single-row tapered roller bearing in the LM361600-series, supplied with a pressed-steel cage as standard.Reading the designation: LM361649 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the LM361600-series code identifies the dimensional series. The 342.9 mm bore, 450.85 mm OD and 66.675 mm width are the metric equivalents of the inch boundary dimensions. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "rolling-mill roll-neck bearings" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "At 342.9 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The LM361600-series inch series at 342.9 mm bore (450.85×66.675 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one LM361649 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "At the 1000 kN rating of LM361649, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 1,200 r/min speed end and heavier preload only where moment stiffness dominates.", "Catalogue reference speed and limiting speed are different limits: the 900 r/min reference is a thermal criterion under load, while the 1,200 r/min limiting value is the mechanical ceiling — observe both.", "The 1000/2200 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM361649 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 361649/610 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Can a single LM361649 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM361649 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM361649 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit LM361649?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 66.675 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." }, { "q": "Is LM361649 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM361649?", "a": "The SKF LM 361649/610 is a single-row tapered roller bearing with 342.9 mm bore, 450.85 mm outer diameter and 66.675 mm width (13.5 × 17.75 × 2.625 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1000 kN, C0 2200 kN, fatigue load limit Pu 180 kN, reference speed 900 r/min, limiting speed 1,200 r/min, mass about 28000 g. It is an open, separable bearing with a pressed-steel cage." } ], "cross_ref": [ { "equiv_sku": "LM361649-610", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM361649-610" ], "locale_variants": {} }, { "sku": "LM361649A-610", "brand": "SKF", "manufacturer_designation": "SKF LM 361649 A/610", "series": "LM361600-series", "type": "tapered_roller", "d_mm": 343.154, "D_mm": 450.85, "B_mm": 66.675, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1000, "static_load_kN": 2200, "fatigue_load_limit_kN": 180, "max_rpm": 1200, "reference_speed_rpm": 900, "limiting_speed_rpm": 1200, "weight_g": 28000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Within the LM361600-series tables, LM 361649 A appears in several rows because SKF lists multiple cup options for the same cone. LM361649A is the 610 variant, with 450.85 mm OD and 66.675 mm width; neighbouring rows on the same cone differ only in the cup but are separate orderable bearings.SKF LM361649A (SKF LM 361649 A/610) is the LM361600-series tapered roller choice for a 343.154 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 450.85×66.675 mm envelope.Digit by digit, LM361649A reads as cone reference / cup reference in the LM361600-series inch series; the 343.154 mm bore, 450.85 mm OD and 66.675 mm width are the metric equivalents of the original inch boundary values. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 1000 kN and C0 2200 kN, the LM361649A pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 1,200 r/min. Because the contact line is tapered, one LM361649A reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 343.154 mm shaft typically takes a m6 seat with an H7 housing bore. Load system: the 1000 kN basic dynamic rating C and 2200 kN static rating C0 give a C0/C balance of 2.20, and dividing C by the 343.154 mm bore yields 2.91 kN per millimetre of journal — a density metric that compares across families; the 180 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 343.154 mm shaft carrying variable duty.", "applications": [ "large industrial mixer shafts", "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "wind-turbine main shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "At 343.154 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The LM361600-series inch series at 343.154 mm bore (450.85×66.675 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of LM361649A pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Do not mix brands or executions inside one LM361649A pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 1000/2200 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM361649A (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 361649 A/610 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is LM361649A interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM361649A?", "a": "The SKF LM 361649 A/610 is a single-row tapered roller bearing with 343.154 mm bore, 450.85 mm outer diameter and 66.675 mm width (13.51 × 17.75 × 2.625 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1000 kN, C0 2200 kN, fatigue load limit Pu 180 kN, reference speed 900 r/min, limiting speed 1,200 r/min, mass about 28000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM361649A inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM361600-series code marks the dimensional series. The metric dimensions 343.154×450.85×66.675 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM361649A mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM361600-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM361649A take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "LM361649A-610", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM361649A-610" ], "locale_variants": {} }, { "sku": "HM262749-710", "brand": "SKF", "manufacturer_designation": "SKF HM 262749/710", "series": "HM262700-series", "type": "tapered_roller", "d_mm": 346.075, "D_mm": 488.95, "B_mm": 95.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1533, "static_load_kN": 3150, "fatigue_load_limit_kN": 255, "max_rpm": 1100, "reference_speed_rpm": 850, "limiting_speed_rpm": 1100, "weight_g": 55000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF HM262749 (SKF HM 262749/710) is the HM262700-series tapered roller choice for a 346.075 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 488.95×95.25 mm envelope.Reading the designation: HM262749 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the HM262700-series code identifies the dimensional series. The 346.075 mm bore, 488.95 mm OD and 95.25 mm width are the metric equivalents of the inch boundary dimensions. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. At 850 r/min reference speed the 71.4 mm-section HM262749 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 1,100 r/min as the mechanical ceiling. A single HM262749 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel. Cross-section geometry: the 71.4 mm half-section ((488.95−346.075)/2) of this HM200-series unit places the roller large-end pitch diameter at roughly 417 mm, and the 95.25 mm axial width is split between cone (52 mm) and cup rib (43 mm) — a geometry that sets the contact angle and, with the 55000 g rotating cone mass, the critical speed at which cage-roller imbalance begins. Why the cup reference matters here: in the HM262700-series tables the HM 262749 cone appears against several cup options. HM262749 is the pairing with 710, and that choice — not the cone — fixes the 488.95 mm OD, the raceway track position and the 95.25 mm assembled width.", "applications": [ "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "rolling-mill roll-neck bearings" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "At 346.075 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The HM262700-series inch series at 346.075 mm bore (488.95×95.25 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the HM262749 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the HM262749 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 1533/3150 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of HM262749 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 262749/710 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of HM262749?", "a": "The SKF HM 262749/710 is a single-row tapered roller bearing with 346.075 mm bore, 488.95 mm outer diameter and 95.25 mm width (13.625 × 19.25 × 3.75 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1533 kN, C0 3150 kN, fatigue load limit Pu 255 kN, reference speed 850 r/min, limiting speed 1,100 r/min, mass about 55000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the HM262749 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM262700-series code marks the dimensional series. The metric dimensions 346.075×488.95×95.25 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in HM262749 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM262700-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single HM262749 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does HM262749 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load HM262749 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "HM262749-710", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "HM262749-710" ], "locale_variants": {} }, { "sku": "L865547-512", "brand": "SKF", "manufacturer_designation": "SKF L 865547/512", "series": "L865500-series", "type": "tapered_roller", "d_mm": 381, "D_mm": 479.425, "B_mm": 49.213, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 638, "static_load_kN": 1500, "fatigue_load_limit_kN": 120, "max_rpm": 1100, "reference_speed_rpm": 800, "limiting_speed_rpm": 1100, "weight_g": 20000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "On the SKF nameplate, L865547 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the L865500-series marking the dimensional series. In SKF suffix language a bare L865547 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. Speed planning uses two different ceilings: 800 r/min thermal reference and 1,100 r/min mechanical limiting speed. For a 381 mm shaft the usual cone seat is m6 with an H7 housing when the inner ring rotates; arrange two L865547 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Dimensional interchange map: within the L8600 series at 381 mm bore, the 479.425 mm OD and 49.213 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 49.2 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 20000 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline. Why the cup reference matters here: in the L865500-series tables the L 865547 cone appears against several cup options. L865547 is the pairing with 512, and that choice — not the cone — fixes the 479.425 mm OD, the raceway track position and the 49.213 mm assembled width.SKF L 865547/512 belongs to the SKF single-row tapered roller range — the 381 mm bore entry in the inch L865500-series, dimensioned 479.425 mm OD and 49.213 mm wide.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "wind-turbine main shafts" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "roller large-end smearing against the cone rib after EP lubricant film failure", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "At 381 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The L865500-series inch series at 381 mm bore (479.425×49.213 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Setting is a design value, not an assembly feel: excessive preload in the L865547 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Setting is a design value, not an assembly feel: excessive preload in the L865547 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.", "Catalogue reference speed and limiting speed are different limits: the 800 r/min reference is a thermal criterion under load, while the 1,100 r/min limiting value is the mechanical ceiling — observe both.", "The 638/1500 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of L865547 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF L 865547/512 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "How does the L865547 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the L865500-series code marks the dimensional series. The metric dimensions 381×479.425×49.213 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in L865547 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (L865500-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single L865547 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does L865547 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load L865547 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." }, { "q": "What shaft and housing fits suit L865547?", "a": "For a rotating shaft under normal load, seat the cone on a m6 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 49.213 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone." } ], "cross_ref": [ { "equiv_sku": "L865547-512", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "L865547-512" ], "locale_variants": {} }, { "sku": "LM567949-910-HA1", "brand": "SKF", "manufacturer_designation": "SKF LM 567949/910/HA1", "series": "LM567900-series", "type": "tapered_roller", "d_mm": 406.4, "D_mm": 549.275, "B_mm": 85.725, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1467, "static_load_kN": 3050, "fatigue_load_limit_kN": 236, "max_rpm": 950, "reference_speed_rpm": 700, "limiting_speed_rpm": 950, "weight_g": 53500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " From a specification standpoint the 910/HA1 cup is the controlling half of LM567949 for housing design — it sets the 549.275 mm OD and the outer abutment diameter — while the LM 567949 cone controls shaft fit at the 406.4 mm bore; the 85.725 mm width is the result of the two together.For a 406.4 mm shaft carrying combined load, SKF lists LM567949 under catalogue execution SKF LM 567949/910/HA1: one open single-row tapered roller bearing in the inch LM567900-series.The code breaks down as cone/cup: the numbers before and after the slash identify the inner and outer ring sets, and the series prefix (LM567900-series) ties the pair to a specific boundary plan. Dimensions 406.4×549.275×85.725 mm are the converted metric envelope. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. At 700 r/min reference speed the 71.4 mm-section LM567949 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 950 r/min as the mechanical ceiling. Specify pairs rather than single units wherever thrust reverses: the tapered contact of LM567949 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Dimensional interchange map: within the LM500 series at 406.4 mm bore, the 549.275 mm OD and 85.725 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 71.4 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 53500 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "offshore winch and drawworks drums" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "At 406.4 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The LM567900-series inch series at 406.4 mm bore (549.275×85.725 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "Do not mix brands or executions inside one LM567949 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.", "When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of LM567949 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.", "Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 549.275 mm cup race release as noise within the first running hours.", "The 1467/3050 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM567949 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 567949/910/HA1 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "Is LM567949 interchangeable with other brands?", "a": "Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing." }, { "q": "What are the dimensions and catalogue data of LM567949?", "a": "The SKF LM 567949/910/HA1 is a single-row tapered roller bearing with 406.4 mm bore, 549.275 mm outer diameter and 85.725 mm width (16 × 21.625 × 3.375 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1467 kN, C0 3050 kN, fatigue load limit Pu 236 kN, reference speed 700 r/min, limiting speed 950 r/min, mass about 53500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM567949 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM567900-series code marks the dimensional series. The metric dimensions 406.4×549.275×85.725 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM567949 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM567900-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM567949 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." } ], "cross_ref": [ { "equiv_sku": "LM567949-910-HA1", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM567949-910-HA1" ], "locale_variants": {} }, { "sku": "LM869448-410", "brand": "SKF", "manufacturer_designation": "SKF LM 869448/410", "series": "LM869400-series", "type": "tapered_roller", "d_mm": 431.8, "D_mm": 571.5, "B_mm": 74.612, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1145, "static_load_kN": 2550, "fatigue_load_limit_kN": 204, "max_rpm": 900, "reference_speed_rpm": 670, "limiting_speed_rpm": 900, "weight_g": 49000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, LM869448 appears as SKF LM 869448/410: an open, single-row tapered roller bearing in the LM869400-series, supplied with a pressed-steel cage as standard.Numbering ties the bearing to its inch-series envelope: LM869448 means a cone and cup matched pair in the LM869400-series series — which is why the 431.8×571.5×74.612 mm outline swaps dimensionally with other inch-series bearings of the same code. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. Selection arithmetic: the C0/C ratio is about 2.23 (static 2550 kN against dynamic 1145 kN), typical of a tapered roller sized for axial capacity, and the 204 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Because the contact line is tapered, one LM869448 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 431.8 mm shaft typically takes a m6 seat with an H7 housing bore. Cross-section geometry: the 69.8 mm half-section ((571.5−431.8)/2) of this LM800-series unit places the roller large-end pitch diameter at roughly 501 mm, and the 74.612 mm axial width is split between cone (41 mm) and cup rib (34 mm) — a geometry that sets the contact angle and, with the 49000 g rotating cone mass, the critical speed at which cage-roller imbalance begins. The cup reference 410 is structural, not a suffix: it identifies the outer ring that, combined with the LM 869448 cone, produces the 431.8/571.5/74.612 mm envelope catalogue-listed as LM869448. Quote the cup number in full when ordering — the LM869400-series tables contain other cups that fit the same cone but change the bearing.", "applications": [ "heavy-duty rolling-mill gearboxes", "large crusher and mineral-processing drives", "wind-turbine main shafts", "heavy-duty rolling-mill gearboxes" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "At 431.8 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The LM869400-series inch series at 431.8 mm bore (571.5×74.612 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common LM869448 mounting error.", "The tapered contact angle creates an induced axial load under pure radial force; include it in the LM869448 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.", "The 49000 g mass and 74.612 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of LM869448.", "The 1145/2550 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of LM869448 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF LM 869448/410 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of LM869448?", "a": "The SKF LM 869448/410 is a single-row tapered roller bearing with 431.8 mm bore, 571.5 mm outer diameter and 74.612 mm width (17 × 22.5 × 2.937 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1145 kN, C0 2550 kN, fatigue load limit Pu 204 kN, reference speed 670 r/min, limiting speed 900 r/min, mass about 49000 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the LM869448 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the LM869400-series code marks the dimensional series. The metric dimensions 431.8×571.5×74.612 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in LM869448 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (LM869400-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single LM869448 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does LM869448 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load LM869448 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "LM869448-410", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "LM869448-410" ], "locale_variants": {} }, { "sku": "L570649-610", "brand": "SKF", "manufacturer_designation": "SKF L 570649/610", "series": "L570600-series", "type": "tapered_roller", "d_mm": 457.2, "D_mm": 573.088, "B_mm": 74.612, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1205, "static_load_kN": 3000, "fatigue_load_limit_kN": 228, "max_rpm": 900, "reference_speed_rpm": 670, "limiting_speed_rpm": 900, "weight_g": 43500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF L 570649/610 belongs to the SKF single-row tapered roller range — the 457.2 mm bore entry in the inch L570600-series, dimensioned 573.088 mm OD and 74.612 mm wide.The L570600-series series assigns 457.2 mm bore, 573.088 mm OD and 74.612 mm width to L570649; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. In SKF suffix language a bare L570649 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 228 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 2.49 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Note the minimum-axial-load requirement: at light radial load and high speed the rollers of L570649 must still be held into the rib contact, which is another reason the catalogue recommends paired mounting with controlled setting. Load system: the 1205 kN basic dynamic rating C and 3000 kN static rating C0 give a C0/C balance of 2.49, and dividing C by the 457.2 mm bore yields 2.64 kN per millimetre of journal — a density metric that compares across families; the 228 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 457.2 mm shaft carrying variable duty. Cup-side note for 610: the outer ring's rib profile and the 573.088 mm outside diameter are cup-specific within the L570600-series tables, so substituting a different cup against the same L 570649 cone changes both the assembled 74.612 mm width and the axial free-play setting of the mounted pair.", "applications": [ "offshore winch and drawworks drums", "rolling-mill roll-neck bearings", "heavy-duty rolling-mill gearboxes", "offshore winch and drawworks drums" ], "failure_modes": [ "cup or cone misalignment when the separable rings are not seated square during mounting", "loose cup rotation in the housing when the specified press fit is not achieved", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At 457.2 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.", "The L570600-series inch series at 457.2 mm bore (573.088×74.612 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.", "At the 1205 kN rating of L570649, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 900 r/min speed end and heavier preload only where moment stiffness dominates.", "At the 1205 kN rating of L570649, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 900 r/min speed end and heavier preload only where moment stiffness dominates.", "The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.", "The 1205/3000 kN ratings are SKF catalogue 17000 values for the basic execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.", "SKF lists several executions of L570649 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF L 570649/610 designation when purchasing and match the execution to the mounting arrangement." ], "faq": [ { "q": "What are the dimensions and catalogue data of L570649?", "a": "The SKF L 570649/610 is a single-row tapered roller bearing with 457.2 mm bore, 573.088 mm outer diameter and 74.612 mm width (18 × 22.563 × 2.937 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1205 kN, C0 3000 kN, fatigue load limit Pu 228 kN, reference speed 670 r/min, limiting speed 900 r/min, mass about 43500 g. It is an open, separable bearing with a pressed-steel cage." }, { "q": "How does the L570649 inch-series designation work?", "a": "Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the L570600-series code marks the dimensional series. The metric dimensions 457.2×573.088×74.612 mm are the converted equivalents of the original inch boundary dimensions." }, { "q": "What do the cone and cup numbers in L570649 mean?", "a": "The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (L570600-series) groups sizes that share the same boundary-dimension plan." }, { "q": "Can a single L570649 take axial load in both directions?", "a": "No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared." }, { "q": "How does L570649 compare with a ball bearing of the same bore?", "a": "A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load L570649 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting." } ], "cross_ref": [ { "equiv_sku": "L570649-610", "equiv_brand": "Timken", "level": "full", "note": "Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB", "extracted_at": "2026-09-28", "last_verified": "2026-09-28", "confidence_score": 0.7, "status": "published", "aliases": [ "L570649-610" ], "locale_variants": {} }, { "sku": "30307R", "brand": "SKF", "manufacturer_designation": "SKF 30307 R", "series": "flanged-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 80, "B_mm": 22.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 88.9, "static_load_kN": 73.5, "fatigue_load_limit_kN": 8.3, "weight_g": 530, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30307R is a single-row tapered roller bearing with a flanged outer ring, listed by SKF in SKF catalogue PUB BU/P1 17000: the integral flange on the cup lets the housing skip a machined shoulder on one side, so axial location comes from the flange face rather than an abutment.Reading the designation: the leading digits 30307 follow the ISO 355 single-row tapered-roller convention (type 3, dimension series, bore code for the 35 mm bore), and the trailing letter marks the flanged outer ring execution — the boundary dimensions 35×80×22.75 mm match the plain-bearing plan, the flange adds only axial location. Where the flange earns its keep: through-bored housings, sheet-metal or cast covers, and split housings where a machined shoulder would be awkward — the 80 mm cup with its flange locates axially without extra parts. The 8.3 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 0.83 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Material and manufacturing detail: the 530 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class. Reversing-thrust shafts need a second tapered bearing facing 30307R; the flange handles location on one side only, it does not make the bearing a double-direction unit.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "belt-driven fan and blower shafts" ], "failure_modes": [ "uneven load sharing in a pair when spacer faces are not parallel to the bore", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "The flange does not change the one-direction thrust rule: 30307R still needs a second tapered bearing facing it on reversing-thrust shafts, with the running clearance set at mounting.", "Check housing face runout where the flange seats: a face out of square cocks the 22.75 mm-wide cup and concentrates load on one rib — the usual root cause of early flanged-bearing noise.", "The flange does not change the one-direction thrust rule: 30307R still needs a second tapered bearing facing it on reversing-thrust shafts, with the running clearance set at mounting.", "The 88.9/73.5 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30307 R designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30307R?", "a": "The SKF 30307 R is a single-row tapered roller bearing with a flanged outer ring with 35 mm bore, 80 mm outer diameter and 22.75 mm overall width (1.378 × 3.15 × 0.896 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 88.9 kN, C0 73.5 kN, fatigue load limit Pu 8.3 kN, reference speed 7,500 r/min, limiting speed 9,000 r/min, mass about 0.53 kg." }, { "q": "What does the flanged outer ring on 30307R do?", "a": "The cup of 30307R carries an integral flange that locates the bearing axially against the housing face, so the housing needs no machined abutment shoulder on the flange side. It simplifies through-bored or cover-mounted housings; the running clearance is still set by cone-versus-cup position at mounting, exactly as for the plain 30307 bearing." }, { "q": "Is 30307R interchangeable with the plain 30307 bearing?", "a": "The boundary dimensions 35×80×22.75 mm match the ISO 355 plan of the base bearing, but the flanged cup is a different order number. It is interchangeable only where the housing provides axial location by other means; where the flange is the locating feature, a plain cup cannot substitute." }, { "q": "Can a single 30307R take axial load in both directions?", "a": "No — like any single-row tapered roller bearing it reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair (O or X arrangement) for reversing thrust." }, { "q": "What shaft and housing fits suit 30307R?", "a": "For a rotating cone on the 35 mm shaft, use a k5 seat; the flanged cup is retained through the flange, so the 80 mm OD seat can be a loose-to-transition fit. Keep housing face runout square so the flange seats without tilting the cup." } ], "cross_ref": [ { "equiv_sku": "30307", "equiv_brand": "SKF", "level": "partial", "note": "Same d/D/T boundary as the plain single-row base bearing, but the flanged cup changes housing location — not a drop-in substitute where the flange is the axial register." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30307R" ], "locale_variants": {}, "max_rpm": 9000, "reference_speed_rpm": 7500, "limiting_speed_rpm": 9000 }, { "sku": "32008XR", "brand": "SKF", "manufacturer_designation": "SKF 32008 XR", "series": "flanged-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 68, "B_mm": 19, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 64.7, "static_load_kN": 71, "fatigue_load_limit_kN": 7.65, "weight_g": 290, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 32008 XR belongs to the SKF flanged tapered-roller range — the 40 mm bore entry dimensioned 68×19 mm, intended for housings where one side has no room for a turned abutment shoulder.The code SKF 32008 XR breaks down as the ISO 355 base bearing 32008 plus the flange suffix: same 40 mm bore, 68 mm OD and 19 mm width as the standard execution, with the cup extended into a locating flange. Substitution caution: a plain 32008 bearing cannot replace 32008XR where the housing has no shoulder on the flange side — the plain cup would lack axial location even though the 40×68×19 mm boundary matches. Selection arithmetic: the C0/C ratio is about 1.10 (static 71 kN against dynamic 64.7 kN), and the 7.65 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. Operating context for the 40 mm bore: a shaft of this diameter typically runs in the medium-bore band of industrial duty, and the 68 mm OD places the housing shoulder near 76 mm outer abutment. Fit selection follows the rotating ring: a rotating cone on the 40 mm shaft takes a k5 seat; the flanged cup is clamped through its flange and does not need a tight housing fit on the 68 mm OD.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "machine-tool spindles" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "Check housing face runout where the flange seats: a face out of square cocks the 19 mm-wide cup and concentrates load on one rib — the usual root cause of early flanged-bearing noise.", "A plain 32008 bearing is not a spare for 32008XR where the flange provides the axial register: same envelope, different location concept — verify the housing design before substituting.", "A plain 32008 bearing is not a spare for 32008XR where the flange provides the axial register: same envelope, different location concept — verify the housing design before substituting.", "The 64.7/71 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32008 XR designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32008XR?", "a": "The SKF 32008 XR is a single-row tapered roller bearing with a flanged outer ring with 40 mm bore, 68 mm outer diameter and 19 mm overall width (1.575 × 2.677 × 0.748 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 64.7 kN, C0 71 kN, fatigue load limit Pu 7.65 kN, reference speed 7,500 r/min, limiting speed 9,500 r/min, mass about 0.29 kg." }, { "q": "What does the flanged outer ring on 32008XR do?", "a": "The cup of 32008XR carries an integral flange that locates the bearing axially against the housing face, so the housing needs no machined abutment shoulder on the flange side. It simplifies through-bored or cover-mounted housings; the running clearance is still set by cone-versus-cup position at mounting, exactly as for the plain 32008 bearing." }, { "q": "Is 32008XR interchangeable with the plain 32008 bearing?", "a": "The boundary dimensions 40×68×19 mm match the ISO 355 plan of the base bearing, but the flanged cup is a different order number. It is interchangeable only where the housing provides axial location by other means; where the flange is the locating feature, a plain cup cannot substitute." }, { "q": "Can a single 32008XR take axial load in both directions?", "a": "No — like any single-row tapered roller bearing it reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair (O or X arrangement) for reversing thrust." }, { "q": "What shaft and housing fits suit 32008XR?", "a": "For a rotating cone on the 40 mm shaft, use a k5 seat; the flanged cup is retained through the flange, so the 68 mm OD seat can be a loose-to-transition fit. Keep housing face runout square so the flange seats without tilting the cup." } ], "cross_ref": [ { "equiv_sku": "32008XR", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32008XR" ], "locale_variants": {}, "max_rpm": 9500, "reference_speed_rpm": 7500, "limiting_speed_rpm": 9500 }, { "sku": "30208R", "brand": "SKF", "manufacturer_designation": "SKF 30208 R", "series": "flanged-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 80, "B_mm": 19.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 75.8, "static_load_kN": 68, "fatigue_load_limit_kN": 7.65, "weight_g": 440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 30208 R belongs to the SKF flanged tapered-roller range — the 40 mm bore entry dimensioned 80×19.75 mm, intended for housings where one side has no room for a turned abutment shoulder.Reading the designation: the leading digits 30208 follow the ISO 355 single-row tapered-roller convention (type 3, dimension series, bore code for the 40 mm bore), and the trailing letter marks the flanged outer ring execution — the boundary dimensions 40×80×19.75 mm match the plain-bearing plan, the flange adds only axial location. Where the flange earns its keep: through-bored housings, sheet-metal or cast covers, and split housings where a machined shoulder would be awkward — the 80 mm cup with its flange locates axially without extra parts. With C 75.8 kN and C0 68 kN, the 30208R sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering the tapered contact induces an axial component under radial load. Dimensional interchange map: within its boundary plan the 40×80×19.75 mm envelope of 30208R is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Reversing-thrust shafts need a second tapered bearing facing 30208R; the flange handles location on one side only, it does not make the bearing a double-direction unit.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "differential and pinion drives" ], "failure_modes": [ "roller large-end smearing against the cone rib after EP lubricant film failure", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "Check housing face runout where the flange seats: a face out of square cocks the 19.75 mm-wide cup and concentrates load on one rib — the usual root cause of early flanged-bearing noise.", "The flange does not change the one-direction thrust rule: 30208R still needs a second tapered bearing facing it on reversing-thrust shafts, with the running clearance set at mounting.", "Do not press 30208R home through the rollers: mounting force for the 40 mm bore seat goes through the cone face only, and the flanged cup is located by its flange, not by pressing the 80 mm OD.", "The 75.8/68 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30208 R designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30208R?", "a": "The SKF 30208 R is a single-row tapered roller bearing with a flanged outer ring with 40 mm bore, 80 mm outer diameter and 19.75 mm overall width (1.575 × 3.15 × 0.778 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 75.8 kN, C0 68 kN, fatigue load limit Pu 7.65 kN, reference speed 7,000 r/min, limiting speed 8,500 r/min, mass about 0.44 kg." }, { "q": "What does the flanged outer ring on 30208R do?", "a": "The cup of 30208R carries an integral flange that locates the bearing axially against the housing face, so the housing needs no machined abutment shoulder on the flange side. It simplifies through-bored or cover-mounted housings; the running clearance is still set by cone-versus-cup position at mounting, exactly as for the plain 30208 bearing." }, { "q": "Is 30208R interchangeable with the plain 30208 bearing?", "a": "The boundary dimensions 40×80×19.75 mm match the ISO 355 plan of the base bearing, but the flanged cup is a different order number. It is interchangeable only where the housing provides axial location by other means; where the flange is the locating feature, a plain cup cannot substitute." }, { "q": "Can a single 30208R take axial load in both directions?", "a": "No — like any single-row tapered roller bearing it reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair (O or X arrangement) for reversing thrust." }, { "q": "What shaft and housing fits suit 30208R?", "a": "For a rotating cone on the 40 mm shaft, use a k5 seat; the flanged cup is retained through the flange, so the 80 mm OD seat can be a loose-to-transition fit. Keep housing face runout square so the flange seats without tilting the cup." } ], "cross_ref": [ { "equiv_sku": "30208", "equiv_brand": "SKF", "level": "partial", "note": "Same d/D/T boundary as the plain single-row base bearing, but the flanged cup changes housing location — not a drop-in substitute where the flange is the axial register." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30208R" ], "locale_variants": {}, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500 }, { "sku": "32309BR", "brand": "SKF", "manufacturer_designation": "SKF 32309 BR", "series": "flanged-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 100, "B_mm": 38.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 166, "static_load_kN": 176, "fatigue_load_limit_kN": 20, "weight_g": 1550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 32309BR appears as SKF 32309 BR: an open, single-row flanged tapered roller bearing for a 45 mm shaft, dimensioned 100 mm OD and 38.25 mm wide with the locating flange formed on the cup.The code SKF 32309 BR breaks down as the ISO 355 base bearing 32309 plus the flange suffix: same 45 mm bore, 100 mm OD and 38.25 mm width as the standard execution, with the cup extended into a locating flange. Substitution caution: a plain 32309 bearing cannot replace 32309BR where the housing has no shoulder on the flange side — the plain cup would lack axial location even though the 45×100×38.25 mm boundary matches. Speed planning uses two different ceilings: 5,000 r/min thermal reference and 6,700 r/min mechanical limiting speed. Assembly datum check: verify the 38.25 mm width against the drawing before clamping — the width is the assembled result and the quickest field check that the correct execution of 32309BR is on the shaft. Reversing-thrust shafts need a second tapered bearing facing 32309BR; the flange handles location on one side only, it does not make the bearing a double-direction unit.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "belt-driven fan and blower shafts" ], "failure_modes": [ "uneven load sharing in a pair when spacer faces are not parallel to the bore", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "The flange does not change the one-direction thrust rule: 32309BR still needs a second tapered bearing facing it on reversing-thrust shafts, with the running clearance set at mounting.", "Do not press 32309BR home through the rollers: mounting force for the 45 mm bore seat goes through the cone face only, and the flanged cup is located by its flange, not by pressing the 100 mm OD.", "The flange face of 32309BR is the axial datum: protect it in handling — a nicked flange face tilts the cup in the housing and shows up as edge loading on the 100 mm OD raceway.", "The 166/176 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32309 BR designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32309BR?", "a": "The SKF 32309 BR is a single-row tapered roller bearing with a flanged outer ring with 45 mm bore, 100 mm outer diameter and 38.25 mm overall width (1.772 × 3.937 × 1.506 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 166 kN, C0 176 kN, fatigue load limit Pu 20 kN, reference speed 5,000 r/min, limiting speed 6,700 r/min, mass about 1.55 kg." }, { "q": "What does the flanged outer ring on 32309BR do?", "a": "The cup of 32309BR carries an integral flange that locates the bearing axially against the housing face, so the housing needs no machined abutment shoulder on the flange side. It simplifies through-bored or cover-mounted housings; the running clearance is still set by cone-versus-cup position at mounting, exactly as for the plain 32309 bearing." }, { "q": "Is 32309BR interchangeable with the plain 32309 bearing?", "a": "The boundary dimensions 45×100×38.25 mm match the ISO 355 plan of the base bearing, but the flanged cup is a different order number. It is interchangeable only where the housing provides axial location by other means; where the flange is the locating feature, a plain cup cannot substitute." }, { "q": "Can a single 32309BR take axial load in both directions?", "a": "No — like any single-row tapered roller bearing it reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair (O or X arrangement) for reversing thrust." }, { "q": "What shaft and housing fits suit 32309BR?", "a": "For a rotating cone on the 45 mm shaft, use a k5 seat; the flanged cup is retained through the flange, so the 100 mm OD seat can be a loose-to-transition fit. Keep housing face runout square so the flange seats without tilting the cup." } ], "cross_ref": [ { "equiv_sku": "32309", "equiv_brand": "SKF", "level": "partial", "note": "Same d/D/T boundary as the plain single-row base bearing, but the flanged cup changes housing location — not a drop-in substitute where the flange is the axial register." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32309BR" ], "locale_variants": {}, "max_rpm": 6700, "reference_speed_rpm": 5000, "limiting_speed_rpm": 6700 }, { "sku": "32311BR", "brand": "SKF", "manufacturer_designation": "SKF 32311 BR", "series": "flanged-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 120, "B_mm": 45.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 233, "static_load_kN": 260, "fatigue_load_limit_kN": 30, "weight_g": 2550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF 32311 BR in SKF catalogue PUB BU/P1 17000 denotes a flanged single-row tapered roller bearing for a 55 mm shaft: combined radial and one-direction axial load, separable mounting, and a cup flange that simplifies housing design.The code SKF 32311 BR breaks down as the ISO 355 base bearing 32311 plus the flange suffix: same 55 mm bore, 120 mm OD and 45.5 mm width as the standard execution, with the cup extended into a locating flange. Substitution caution: a plain 32311 bearing cannot replace 32311BR where the housing has no shoulder on the flange side — the plain cup would lack axial location even though the 55×120×45.5 mm boundary matches. Speed planning uses two different ceilings: 4,300 r/min thermal reference and 5,600 r/min mechanical limiting speed. Dimensional interchange map: within its boundary plan the 55×120×45.5 mm envelope of 32311BR is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Fit selection follows the rotating ring: a rotating cone on the 55 mm shaft takes a k5 seat; the flanged cup is clamped through its flange and does not need a tight housing fit on the 120 mm OD.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The flange does not change the one-direction thrust rule: 32311BR still needs a second tapered bearing facing it on reversing-thrust shafts, with the running clearance set at mounting.", "The flange does not change the one-direction thrust rule: 32311BR still needs a second tapered bearing facing it on reversing-thrust shafts, with the running clearance set at mounting.", "The flange face of 32311BR is the axial datum: protect it in handling — a nicked flange face tilts the cup in the housing and shows up as edge loading on the 120 mm OD raceway.", "The 233/260 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32311 BR designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32311BR?", "a": "The SKF 32311 BR is a single-row tapered roller bearing with a flanged outer ring with 55 mm bore, 120 mm outer diameter and 45.5 mm overall width (2.165 × 4.724 × 1.791 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 233 kN, C0 260 kN, fatigue load limit Pu 30 kN, reference speed 4,300 r/min, limiting speed 5,600 r/min, mass about 2.55 kg." }, { "q": "What does the flanged outer ring on 32311BR do?", "a": "The cup of 32311BR carries an integral flange that locates the bearing axially against the housing face, so the housing needs no machined abutment shoulder on the flange side. It simplifies through-bored or cover-mounted housings; the running clearance is still set by cone-versus-cup position at mounting, exactly as for the plain 32311 bearing." }, { "q": "Is 32311BR interchangeable with the plain 32311 bearing?", "a": "The boundary dimensions 55×120×45.5 mm match the ISO 355 plan of the base bearing, but the flanged cup is a different order number. It is interchangeable only where the housing provides axial location by other means; where the flange is the locating feature, a plain cup cannot substitute." }, { "q": "Can a single 32311BR take axial load in both directions?", "a": "No — like any single-row tapered roller bearing it reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair (O or X arrangement) for reversing thrust." }, { "q": "What shaft and housing fits suit 32311BR?", "a": "For a rotating cone on the 55 mm shaft, use a k5 seat; the flanged cup is retained through the flange, so the 120 mm OD seat can be a loose-to-transition fit. Keep housing face runout square so the flange seats without tilting the cup." } ], "cross_ref": [ { "equiv_sku": "32311", "equiv_brand": "SKF", "level": "partial", "note": "Same d/D/T boundary as the plain single-row base bearing, but the flanged cup changes housing location — not a drop-in substitute where the flange is the axial register." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32311BR" ], "locale_variants": {}, "max_rpm": 5600, "reference_speed_rpm": 4300, "limiting_speed_rpm": 5600 }, { "sku": "33113R", "brand": "SKF", "manufacturer_designation": "SKF 33113 R", "series": "flanged-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 110, "B_mm": 34, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 175, "static_load_kN": 208, "fatigue_load_limit_kN": 24, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 33113 R is a 65×110×34 mm flanged single-row tapered roller bearing — a separable cone-and-cup unit whose cup carries an integral axial-location flange for through-bored housings.Numbering ties the bearing to its envelope: 33113 means tapered-roller type 3 with a 65 mm bore, and the flanged-execution suffix tells the housing designer that axial location is built into the cup at the 110 mm OD. The flange face is ground square to the cup raceway; when pulling the assembly datum from the flange, verify the housing face runout so the 34 mm-wide cup is not tilted against the cone. The 22.5 mm radial section height ((110−65)/2) and 1300 g catalogue mass frame a 65 mm bore bearing rated at 175 kN C — roughly 2.69 kN of dynamic capacity per millimetre of bore before application factors. Load system: C 175 kN against C0 208 kN gives a 1.19 balance, and 2.69 kN of dynamic capacity per millimetre of the 65 mm bore is the density figure to compare against neighbouring sizes. Fit selection follows the rotating ring: a rotating cone on the 65 mm shaft takes a k5 seat; the flanged cup is clamped through its flange and does not need a tight housing fit on the 110 mm OD.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "A plain 33113 bearing is not a spare for 33113R where the flange provides the axial register: same envelope, different location concept — verify the housing design before substituting.", "The flange face of 33113R is the axial datum: protect it in handling — a nicked flange face tilts the cup in the housing and shows up as edge loading on the 110 mm OD raceway.", "Check housing face runout where the flange seats: a face out of square cocks the 34 mm-wide cup and concentrates load on one rib — the usual root cause of early flanged-bearing noise.", "The 175/208 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33113 R designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33113R?", "a": "The SKF 33113 R is a single-row tapered roller bearing with a flanged outer ring with 65 mm bore, 110 mm outer diameter and 34 mm overall width (2.559 × 4.331 × 1.339 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 175 kN, C0 208 kN, fatigue load limit Pu 24 kN, reference speed 4,800 r/min, limiting speed 5,600 r/min, mass about 1.30 kg." }, { "q": "What does the flanged outer ring on 33113R do?", "a": "The cup of 33113R carries an integral flange that locates the bearing axially against the housing face, so the housing needs no machined abutment shoulder on the flange side. It simplifies through-bored or cover-mounted housings; the running clearance is still set by cone-versus-cup position at mounting, exactly as for the plain 33113 bearing." }, { "q": "Is 33113R interchangeable with the plain 33113 bearing?", "a": "The boundary dimensions 65×110×34 mm match the ISO 355 plan of the base bearing, but the flanged cup is a different order number. It is interchangeable only where the housing provides axial location by other means; where the flange is the locating feature, a plain cup cannot substitute." }, { "q": "Can a single 33113R take axial load in both directions?", "a": "No — like any single-row tapered roller bearing it reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair (O or X arrangement) for reversing thrust." }, { "q": "What shaft and housing fits suit 33113R?", "a": "For a rotating cone on the 65 mm shaft, use a k5 seat; the flanged cup is retained through the flange, so the 110 mm OD seat can be a loose-to-transition fit. Keep housing face runout square so the flange seats without tilting the cup." } ], "cross_ref": [ { "equiv_sku": "33113", "equiv_brand": "SKF", "level": "partial", "note": "Same d/D/T boundary as the plain single-row base bearing, but the flanged cup changes housing location — not a drop-in substitute where the flange is the axial register." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33113R" ], "locale_variants": {}, "max_rpm": 5600, "reference_speed_rpm": 4800, "limiting_speed_rpm": 5600 }, { "sku": "30313R", "brand": "SKF", "manufacturer_designation": "SKF 30313 R", "series": "flanged-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 140, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 240, "static_load_kN": 228, "fatigue_load_limit_kN": 27.5, "weight_g": 2500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 30313 R belongs to the SKF flanged tapered-roller range — the 65 mm bore entry dimensioned 140×36 mm, intended for housings where one side has no room for a turned abutment shoulder.Numbering ties the bearing to its envelope: 30313 means tapered-roller type 3 with a 65 mm bore, and the flanged-execution suffix tells the housing designer that axial location is built into the cup at the 140 mm OD. Substitution caution: a plain 30313 bearing cannot replace 30313R where the housing has no shoulder on the flange side — the plain cup would lack axial location even though the 65×140×36 mm boundary matches. At 4,000 r/min reference speed the 37.5 mm-section 30313R is governed thermally by setting and lubricant flow; grease or oil selection should be made against that value, with 4,800 r/min as the mechanical ceiling. Cross-section geometry: the 37.5 mm half-section ((140−65)/2) places the roller pitch diameter near 102 mm, and the 36 mm axial width sets the abutment depth — geometry that fixes the contact angle behaviour of 30313R. Like any single-row tapered bearing, 30313R reacts thrust in one direction only — mount it against a second bearing in O or X arrangement and set the running clearance by procedure, not by feel.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "marine deck machinery shafts" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "A plain 30313 bearing is not a spare for 30313R where the flange provides the axial register: same envelope, different location concept — verify the housing design before substituting.", "A plain 30313 bearing is not a spare for 30313R where the flange provides the axial register: same envelope, different location concept — verify the housing design before substituting.", "The flange does not change the one-direction thrust rule: 30313R still needs a second tapered bearing facing it on reversing-thrust shafts, with the running clearance set at mounting.", "The 240/228 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30313 R designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30313R?", "a": "The SKF 30313 R is a single-row tapered roller bearing with a flanged outer ring with 65 mm bore, 140 mm outer diameter and 36 mm overall width (2.559 × 5.512 × 1.417 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 240 kN, C0 228 kN, fatigue load limit Pu 27.5 kN, reference speed 4,000 r/min, limiting speed 4,800 r/min, mass about 2.50 kg." }, { "q": "What does the flanged outer ring on 30313R do?", "a": "The cup of 30313R carries an integral flange that locates the bearing axially against the housing face, so the housing needs no machined abutment shoulder on the flange side. It simplifies through-bored or cover-mounted housings; the running clearance is still set by cone-versus-cup position at mounting, exactly as for the plain 30313 bearing." }, { "q": "Is 30313R interchangeable with the plain 30313 bearing?", "a": "The boundary dimensions 65×140×36 mm match the ISO 355 plan of the base bearing, but the flanged cup is a different order number. It is interchangeable only where the housing provides axial location by other means; where the flange is the locating feature, a plain cup cannot substitute." }, { "q": "Can a single 30313R take axial load in both directions?", "a": "No — like any single-row tapered roller bearing it reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair (O or X arrangement) for reversing thrust." }, { "q": "What shaft and housing fits suit 30313R?", "a": "For a rotating cone on the 65 mm shaft, use a k5 seat; the flanged cup is retained through the flange, so the 140 mm OD seat can be a loose-to-transition fit. Keep housing face runout square so the flange seats without tilting the cup." } ], "cross_ref": [ { "equiv_sku": "30313", "equiv_brand": "SKF", "level": "partial", "note": "Same d/D/T boundary as the plain single-row base bearing, but the flanged cup changes housing location — not a drop-in substitute where the flange is the axial register." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30313R" ], "locale_variants": {}, "max_rpm": 4800, "reference_speed_rpm": 4000, "limiting_speed_rpm": 4800 }, { "sku": "31305-DF", "brand": "SKF", "manufacturer_designation": "SKF 31305/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 25, "D_mm": 62, "B_mm": 36.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 79.9, "static_load_kN": 80, "fatigue_load_limit_kN": 8.65, "weight_g": 550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF 31305/DF in SKF catalogue PUB BU/P1 17000 denotes two single-row tapered roller bearings supplied as a matched face-to-face (X) matched pair set for a 25 mm shaft — one order number, one factory setting.On the SKF nameplate, 31305-DF reads as base 31305 in a /DF matched execution — the suffix is part of the order number because a matched set is ground for a specific axial clearance and cannot be assembled from loose single bearings. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 36.5 mm overall width of 31305-DF is the axial space the pair occupies. The C0/C balance of the pair is about 1.00; combined with the 8.65 kN fatigue limit this frames a set sized for reversing combined load on a 25 mm shaft rather than for pure radial duty. Dimensional interchange map: within its boundary plan the 25×62×36.5 mm envelope of 31305-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Thermal behaviour of the pair: heat generated in the 25 mm bore cones flows along the shaft and changes the setting; the /DF clearance class is chosen for the catalogue speed range 6,700–11,000 r/min, so re-select the clearance class if the application runs hotter. Clamp the assembled pair axially through the cones — never through the rollers — and verify the 36.5 mm overall width against the catalogue value before final torquing of the shaft nut.", "applications": [ "light-duty gearbox input/output shafts", "electric-motor pinion shafts", "steering knuckles and small differentials", "light-duty gearbox input/output shafts" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "fretting corrosion on a loose rotating shaft seat", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Replace 31305-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "Setting is built into 31305-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Replace 31305-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 79.9/80 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 31305/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 31305-DF?", "a": "The SKF 31305/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 25 mm bore, 62 mm outer diameter and 36.5 mm overall width (0.984 × 2.441 × 1.437 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 79.9 kN, C0 80 kN, fatigue load limit Pu 8.65 kN, reference speed 6,700 r/min, limiting speed 11,000 r/min, mass about 0.55 kg." }, { "q": "What does the /DF suffix on 31305-DF mean?", "a": "The base 31305 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 31305-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 79.9 kN dynamic and C0 80 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 31305 table values." }, { "q": "Can 31305-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 25 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 25 mm bore." } ], "cross_ref": [ { "equiv_sku": "31305", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "31305-DF" ], "locale_variants": {}, "max_rpm": 11000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 11000 }, { "sku": "30206-DF", "brand": "SKF", "manufacturer_designation": "SKF 30206/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 62, "B_mm": 34.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 85.7, "static_load_kN": 88, "fatigue_load_limit_kN": 9.65, "weight_g": 480, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 30206/DF belongs to the SKF matched tapered-roller range — the 30 mm bore entry in face-to-face (X) matched pair arrangement, dimensioned 62 mm OD and 34.5 mm overall width for the pair.On the SKF nameplate, 30206-DF reads as base 30206 in a /DF matched execution — the suffix is part of the order number because a matched set is ground for a specific axial clearance and cannot be assembled from loose single bearings. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 34.5 mm overall width of 30206-DF is the axial space the pair occupies. Catalogue mass 480 g covers both bearings and the ground spacer of 30206-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance. Dimensional interchange map: within its boundary plan the 30×62×34.5 mm envelope of 30206-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Thermal behaviour of the pair: heat generated in the 30 mm bore cones flows along the shaft and changes the setting; the /DF clearance class is chosen for the catalogue speed range 7,500–11,000 r/min, so re-select the clearance class if the application runs hotter. Do not separate 30206-DF into single-bearing service stock — as individual bearings the components are not interchangeable with catalogue single-row executions because the rings are ground for the set.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "machine-tool spindles" ], "failure_modes": [ "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Replace 30206-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "Setting is built into 30206-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Clamp the 30206-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "The 85.7/88 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30206/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30206-DF?", "a": "The SKF 30206/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 30 mm bore, 62 mm outer diameter and 34.5 mm overall width (1.181 × 2.441 × 1.358 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 85.7 kN, C0 88 kN, fatigue load limit Pu 9.65 kN, reference speed 7,500 r/min, limiting speed 11,000 r/min, mass about 0.48 kg." }, { "q": "What does the /DF suffix on 30206-DF mean?", "a": "The base 30206 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 30206-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 85.7 kN dynamic and C0 88 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30206 table values." }, { "q": "Can 30206-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 30 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 30 mm bore." } ], "cross_ref": [ { "equiv_sku": "30206-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "30206", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30206-DF" ], "locale_variants": {}, "max_rpm": 11000, "reference_speed_rpm": 7500, "limiting_speed_rpm": 11000 }, { "sku": "32206-DF", "brand": "SKF", "manufacturer_designation": "SKF 32206/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 62, "B_mm": 42.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 106, "static_load_kN": 116, "fatigue_load_limit_kN": 12.7, "weight_g": 590, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Load sharing in 32206-DF depends on spacer face parallelism; a cocked spacer concentrates the reversing thrust on one bearing of the pair and shows up as asymmetric raceway wear at overhaul. Clamp the assembled pair axially through the cones — never through the rollers — and verify the 42.5 mm overall width against the catalogue value before final torquing of the shaft nut.The SKF 32206/DF is a 30×62×42.5 mm matched tapered-roller set — two single-row bearings in face-to-face (X) matched pair arrangement, ground and shipped together with the axial clearance fixed at the factory.The code breaks down as base bearing 32206 plus matched-set suffix /DF: two bearings of the 30 mm bore size, paired face-to-face (X) matched pair, with the 42.5 mm overall width spanning the whole arrangement. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 32206-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 30 mm bore. With a pair mass of 590 g across the 30×62×42.5 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Dimensional interchange map: within its boundary plan the 30×62×42.5 mm envelope of 32206-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "Clamp the 32206-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Setting is built into 32206-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Clamp the 32206-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "The 106/116 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32206/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32206-DF?", "a": "The SKF 32206/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 30 mm bore, 62 mm outer diameter and 42.5 mm overall width (1.181 × 2.441 × 1.673 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 106 kN, C0 116 kN, fatigue load limit Pu 12.7 kN, reference speed 7,500 r/min, limiting speed 11,000 r/min, mass about 0.59 kg." }, { "q": "What does the /DF suffix on 32206-DF mean?", "a": "The base 32206 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32206-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 106 kN dynamic and C0 116 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32206 table values." }, { "q": "Can 32206-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 30 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 30 mm bore." } ], "cross_ref": [ { "equiv_sku": "32206", "equiv_brand": "FAG", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32206-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32206-DF" ], "locale_variants": {}, "max_rpm": 11000, "reference_speed_rpm": 7500, "limiting_speed_rpm": 11000 }, { "sku": "31306-DF", "brand": "SKF", "manufacturer_designation": "SKF 31306/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 72, "B_mm": 41.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 100, "static_load_kN": 100, "fatigue_load_limit_kN": 11.4, "weight_g": 820, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Lubrication for the pair should be sized against the combined 41.5 mm width and 820 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.The SKF 31306/DF is a 30×72×41.5 mm matched tapered-roller set — two single-row bearings in face-to-face (X) matched pair arrangement, ground and shipped together with the axial clearance fixed at the factory.On the SKF nameplate, 31306-DF reads as base 31306 in a /DF matched execution — the suffix is part of the order number because a matched set is ground for a specific axial clearance and cannot be assembled from loose single bearings. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 41.5 mm overall width of 31306-DF is the axial space the pair occupies. Catalogue mass 820 g covers both bearings and the ground spacer of 31306-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance. Operating context for the 30 mm bore: a shaft of this diameter typically runs in the medium-bore band of industrial duty, and the 72 mm OD places the housing shoulder near 80 mm outer abutment. Load sharing in 31306-DF depends on spacer face parallelism; a cocked spacer concentrates the reversing thrust on one bearing of the pair and shows up as asymmetric raceway wear at overhaul.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "belt-driven fan and blower shafts" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Clamp the 31306-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 31306-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 31306-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "The 100/100 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 31306/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 31306-DF?", "a": "The SKF 31306/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 30 mm bore, 72 mm outer diameter and 41.5 mm overall width (1.181 × 2.835 × 1.634 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 100 kN, C0 100 kN, fatigue load limit Pu 11.4 kN, reference speed 5,600 r/min, limiting speed 9,500 r/min, mass about 0.82 kg." }, { "q": "What does the /DF suffix on 31306-DF mean?", "a": "The base 31306 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 31306-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 100 kN dynamic and C0 100 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 31306 table values." }, { "q": "Can 31306-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 30 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 30 mm bore." } ], "cross_ref": [ { "equiv_sku": "31306", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "31306-DF" ], "locale_variants": {}, "max_rpm": 9500, "reference_speed_rpm": 5600, "limiting_speed_rpm": 9500 }, { "sku": "30306-DF", "brand": "SKF", "manufacturer_designation": "SKF 30306/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 72, "B_mm": 41.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 119, "static_load_kN": 112, "fatigue_load_limit_kN": 12.7, "weight_g": 810, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The code breaks down as base bearing 30306 plus matched-set suffix /DF: two bearings of the 30 mm bore size, paired face-to-face (X) matched pair, with the 41.5 mm overall width spanning the whole arrangement. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 30306-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 30 mm bore. Selection arithmetic: the catalogue C 119 kN and C0 112 kN are ratings of the complete pair, not of one bearing — never halve them back to a single-row figure when checking L10 life, and use the pair Pu 12.7 kN as the fatigue floor. Material and manufacturing detail: the 810 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class. Spacer discipline: the spacer between the two bearings of 30306-DF is ground to the individual set — it carries a serial link to the pair, so never swap spacers between sets of the same designation. Lubrication for the pair should be sized against the combined 41.5 mm width and 810 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.In SKF catalogue PUB BU/P1 17000, 30306-DF appears as SKF 30306/DF: a matched face-to-face (X) matched pair pair for a 30 mm shaft, rated as a set at C 119 kN and C0 112 kN.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "machine-tool spindles" ], "failure_modes": [ "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "A matched /DF set is ground as one system: never separate the two bearings of 30306-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "Setting is built into 30306-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Replace 30306-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 119/112 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30306/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30306-DF?", "a": "The SKF 30306/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 30 mm bore, 72 mm outer diameter and 41.5 mm overall width (1.181 × 2.835 × 1.634 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 119 kN, C0 112 kN, fatigue load limit Pu 12.7 kN, reference speed 6,700 r/min, limiting speed 10,000 r/min, mass about 0.81 kg." }, { "q": "What does the /DF suffix on 30306-DF mean?", "a": "The base 30306 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 30306-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 119 kN dynamic and C0 112 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30306 table values." }, { "q": "Can 30306-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 30 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 30 mm bore." } ], "cross_ref": [ { "equiv_sku": "30306-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "30306", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30306-DF" ], "locale_variants": {}, "max_rpm": 10000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 10000 }, { "sku": "32007X-DF", "brand": "SKF", "manufacturer_designation": "SKF 32007 X/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 62, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 89.7, "static_load_kN": 108, "fatigue_load_limit_kN": 11.6, "weight_g": 460, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Material and manufacturing detail: the 460 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class. Setting note for 32007X-DF: the axial clearance is set at the factory by selective spacer grinding for the /DF execution; in service, re-checking end play after the first thermal cycle catches seating relaxation before it becomes roller skid. Lubrication for the pair should be sized against the combined 36 mm width and 460 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.32007X-DF (SKF 32007 X/DF) is the face-to-face (X) matched pair matched-set choice for a 35 mm shaft: a pair of tapered roller bearings whose combined envelope is 62×36 mm, delivered ready to mount with controlled internal clearance.Numbering ties the set to its envelope: base 32007 X fixes the 35 mm bore and 62 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 36 mm width is the combined pair dimension. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 32007X-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 35 mm bore. The C0/C balance of the pair is about 1.20; combined with the 11.6 kN fatigue limit this frames a set sized for reversing combined load on a 35 mm shaft rather than for pure radial duty.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "industrial gearbox shafts and reducers" ], "failure_modes": [ "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "hard-particle indentation of the tapered raceway in unfiltered oil", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Replace 32007X-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32007X-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Clamp the 32007X-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "The 89.7/108 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32007 X/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32007X-DF?", "a": "The SKF 32007 X/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 35 mm bore, 62 mm outer diameter and 36 mm overall width (1.378 × 2.441 × 1.417 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 89.7 kN, C0 108 kN, fatigue load limit Pu 11.6 kN, reference speed 7,000 r/min, limiting speed 10,000 r/min, mass about 0.46 kg." }, { "q": "What does the /DF suffix on 32007X-DF mean?", "a": "The base 32007 X is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32007X-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 89.7 kN dynamic and C0 108 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32007 X table values." }, { "q": "Can 32007X-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 35 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 35 mm bore." } ], "cross_ref": [ { "equiv_sku": "32007X", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32007X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32007X-DF" ], "locale_variants": {}, "max_rpm": 10000, "reference_speed_rpm": 7000, "limiting_speed_rpm": 10000 }, { "sku": "32207-DF", "brand": "SKF", "manufacturer_designation": "SKF 32207/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 72, "B_mm": 48.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 139, "static_load_kN": 156, "fatigue_load_limit_kN": 17, "weight_g": 910, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 35 mm rotating shaft) and square abutments.32207-DF is a matched pair of single-row tapered roller bearings arranged face-to-face (X) matched pair, supplied by SKF in SKF catalogue PUB BU/P1 17000 as one factory-set unit: the two bearings, spacers and setting are matched together and must not be mixed with other sets.Numbering ties the set to its envelope: base 32207 fixes the 35 mm bore and 72 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 48.5 mm width is the combined pair dimension. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 48.5 mm overall width of 32207-DF is the axial space the pair occupies. With a pair mass of 910 g across the 35×72×48.5 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Material and manufacturing detail: the 910 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class. When a matched /DF set like 32207-DF is replaced, replace the whole set: mixing a new bearing with a worn partner from the old set leaves the clearance and load sharing of the pair undefined.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "automotive and light-truck wheel hubs" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Setting is built into 32207-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Setting is built into 32207-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "A matched /DF set is ground as one system: never separate the two bearings of 32207-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "The 139/156 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32207/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32207-DF?", "a": "The SKF 32207/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 35 mm bore, 72 mm outer diameter and 48.5 mm overall width (1.378 × 2.835 × 1.909 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 139 kN, C0 156 kN, fatigue load limit Pu 17 kN, reference speed 6,300 r/min, limiting speed 9,500 r/min, mass about 0.91 kg." }, { "q": "What does the /DF suffix on 32207-DF mean?", "a": "The base 32207 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32207-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 139 kN dynamic and C0 156 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32207 table values." }, { "q": "Can 32207-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 35 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 35 mm bore." } ], "cross_ref": [ { "equiv_sku": "32207", "equiv_brand": "FAG", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32207-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32207-DF" ], "locale_variants": {}, "max_rpm": 9500, "reference_speed_rpm": 6300, "limiting_speed_rpm": 9500 }, { "sku": "33207-DF", "brand": "SKF", "manufacturer_designation": "SKF 33207/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 72, "B_mm": 56, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 178, "static_load_kN": 212, "fatigue_load_limit_kN": 23.6, "weight_g": 1100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Operating context for the 35 mm bore: a shaft of this diameter typically runs in the medium-bore band of industrial duty, and the 72 mm OD places the housing shoulder near 80 mm outer abutment. Thermal behaviour of the pair: heat generated in the 35 mm bore cones flows along the shaft and changes the setting; the /DF clearance class is chosen for the catalogue speed range 6,300–9,500 r/min, so re-select the clearance class if the application runs hotter. A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 35 mm rotating shaft) and square abutments.For a 35 mm shaft carrying reversing axial load, SKF lists 33207-DF under catalogue execution SKF 33207/DF: a factory-matched face-to-face (X) matched pair tapered-roller pair, set and measured as one unit.Digit by digit, 33207-DF reads as the ISO 355 base bearing 33207 supplied as a face-to-face (X) matched pair matched pair (/DF); the 35 mm bore and 72 mm OD are per-bearing, the 56 mm width is for the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 33207-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 35 mm bore. Speed planning for the set uses the catalogue pair values: 6,300 r/min thermal reference and 9,500 r/min mechanical limiting speed — a matched pair runs warmer than one bearing because two roller sets share the 56 mm space.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "industrial gearbox shafts and reducers" ], "failure_modes": [ "roller large-end smearing against the cone rib after EP lubricant film failure", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Replace 33207-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 33207-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Setting is built into 33207-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "The 178/212 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33207/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33207-DF?", "a": "The SKF 33207/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 35 mm bore, 72 mm outer diameter and 56 mm overall width (1.378 × 2.835 × 2.205 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 178 kN, C0 212 kN, fatigue load limit Pu 23.6 kN, reference speed 6,300 r/min, limiting speed 9,500 r/min, mass about 1.10 kg." }, { "q": "What does the /DF suffix on 33207-DF mean?", "a": "The base 33207 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33207-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 178 kN dynamic and C0 212 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33207 table values." }, { "q": "Can 33207-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 35 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 35 mm bore." } ], "cross_ref": [ { "equiv_sku": "33207-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "33207", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33207-DF" ], "locale_variants": {}, "max_rpm": 9500, "reference_speed_rpm": 6300, "limiting_speed_rpm": 9500 }, { "sku": "31307-DF", "brand": "SKF", "manufacturer_designation": "SKF 31307/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 80, "B_mm": 45.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 129, "static_load_kN": 134, "fatigue_load_limit_kN": 15.6, "weight_g": 1100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "31307-DF is a matched pair of single-row tapered roller bearings arranged face-to-face (X) matched pair, supplied by SKF in SKF catalogue PUB BU/P1 17000 as one factory-set unit: the two bearings, spacers and setting are matched together and must not be mixed with other sets.Digit by digit, 31307-DF reads as the ISO 355 base bearing 31307 supplied as a face-to-face (X) matched pair matched pair (/DF); the 35 mm bore and 80 mm OD are per-bearing, the 45.5 mm width is for the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 31307-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 35 mm bore. Catalogue mass 1100 g covers both bearings and the ground spacer of 31307-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance. Cross-section geometry: the 22.5 mm half-section ((80−35)/2) places the roller pitch diameter near 57 mm, and the 45.5 mm axial width sets the abutment depth — geometry that fixes the contact angle behaviour of 31307-DF. When a matched /DF set like 31307-DF is replaced, replace the whole set: mixing a new bearing with a worn partner from the old set leaves the clearance and load sharing of the pair undefined. Do not separate 31307-DF into single-bearing service stock — as individual bearings the components are not interchangeable with catalogue single-row executions because the rings are ground for the set.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "automotive and light-truck wheel hubs" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "electrical pitting on VFD-driven shafts without grounding protection", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Setting is built into 31307-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 31307-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "O and X arrangements are not interchangeable by turning the set around: 31307-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "The 129/134 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 31307/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 31307-DF?", "a": "The SKF 31307/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 35 mm bore, 80 mm outer diameter and 45.5 mm overall width (1.378 × 3.15 × 1.791 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 129 kN, C0 134 kN, fatigue load limit Pu 15.6 kN, reference speed 5,000 r/min, limiting speed 8,500 r/min, mass about 1.10 kg." }, { "q": "What does the /DF suffix on 31307-DF mean?", "a": "The base 31307 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 31307-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 129 kN dynamic and C0 134 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 31307 table values." }, { "q": "Can 31307-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 35 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 35 mm bore." } ], "cross_ref": [ { "equiv_sku": "31307", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "31307-DF" ], "locale_variants": {}, "max_rpm": 8500, "reference_speed_rpm": 5000, "limiting_speed_rpm": 8500 }, { "sku": "30307-DF", "brand": "SKF", "manufacturer_designation": "SKF 30307/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 80, "B_mm": 45.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 152, "static_load_kN": 150, "fatigue_load_limit_kN": 16.6, "weight_g": 1050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 35 mm shaft carrying reversing axial load, SKF lists 30307-DF under catalogue execution SKF 30307/DF: a factory-matched face-to-face (X) matched pair tapered-roller pair, set and measured as one unit.The code breaks down as base bearing 30307 plus matched-set suffix /DF: two bearings of the 35 mm bore size, paired face-to-face (X) matched pair, with the 45.5 mm overall width spanning the whole arrangement. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 30307-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 35 mm bore. Speed planning for the set uses the catalogue pair values: 6,000 r/min thermal reference and 9,000 r/min mechanical limiting speed — a matched pair runs warmer than one bearing because two roller sets share the 45.5 mm space. Assembly datum check: verify the 45.5 mm width against the drawing before clamping — the width is the assembled result and the quickest field check that the correct execution of 30307-DF is on the shaft. When a matched /DF set like 30307-DF is replaced, replace the whole set: mixing a new bearing with a worn partner from the old set leaves the clearance and load sharing of the pair undefined. The rotating cones of 30307-DF take a k5 seat on the 35 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "automotive and light-truck wheel hubs" ], "failure_modes": [ "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "grease degradation after long shelf storage without rotation or re-greasing", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 30307-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Clamp the 30307-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Replace 30307-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 152/150 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30307/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30307-DF?", "a": "The SKF 30307/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 35 mm bore, 80 mm outer diameter and 45.5 mm overall width (1.378 × 3.15 × 1.791 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 152 kN, C0 150 kN, fatigue load limit Pu 16.6 kN, reference speed 6,000 r/min, limiting speed 9,000 r/min, mass about 1.05 kg." }, { "q": "What does the /DF suffix on 30307-DF mean?", "a": "The base 30307 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 30307-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 152 kN dynamic and C0 150 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30307 table values." }, { "q": "Can 30307-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 35 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 35 mm bore." } ], "cross_ref": [ { "equiv_sku": "30307-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "30307", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30307-DF" ], "locale_variants": {}, "max_rpm": 9000, "reference_speed_rpm": 6000, "limiting_speed_rpm": 9000 }, { "sku": "33108-DF", "brand": "SKF", "manufacturer_designation": "SKF 33108/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 75, "B_mm": 52, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 167, "static_load_kN": 208, "fatigue_load_limit_kN": 22.8, "weight_g": 1050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Operating context for the 40 mm bore: a shaft of this diameter typically runs in the medium-bore band of industrial duty, and the 75 mm OD places the housing shoulder near 83 mm outer abutment. Spacer discipline: the spacer between the two bearings of 33108-DF is ground to the individual set — it carries a serial link to the pair, so never swap spacers between sets of the same designation. Lubrication for the pair should be sized against the combined 52 mm width and 1050 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.Ordering number SKF 33108/DF in SKF catalogue PUB BU/P1 17000 denotes two single-row tapered roller bearings supplied as a matched face-to-face (X) matched pair set for a 40 mm shaft — one order number, one factory setting.Reading the designation: 33108 is the ISO 355 single-row base bearing (40 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 40×75×52 mm; the width covers both bearings of the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 33108-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 40 mm bore. With a pair mass of 1050 g across the 40×75×52 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "belt-driven fan and blower shafts" ], "failure_modes": [ "roller large-end smearing against the cone rib after EP lubricant film failure", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "Setting is built into 33108-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Setting is built into 33108-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 33108-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "The 167/208 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33108/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33108-DF?", "a": "The SKF 33108/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 40 mm bore, 75 mm outer diameter and 52 mm overall width (1.575 × 2.953 × 2.047 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 167 kN, C0 208 kN, fatigue load limit Pu 22.8 kN, reference speed 6,000 r/min, limiting speed 9,000 r/min, mass about 1.05 kg." }, { "q": "What does the /DF suffix on 33108-DF mean?", "a": "The base 33108 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33108-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 167 kN dynamic and C0 208 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33108 table values." }, { "q": "Can 33108-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 40 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 40 mm bore." } ], "cross_ref": [ { "equiv_sku": "33108-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "33108", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33108-DF" ], "locale_variants": {}, "max_rpm": 9000, "reference_speed_rpm": 6000, "limiting_speed_rpm": 9000 }, { "sku": "30208-DF", "brand": "SKF", "manufacturer_designation": "SKF 30208/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 80, "B_mm": 39.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 130, "static_load_kN": 137, "fatigue_load_limit_kN": 15.3, "weight_g": 870, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Thermal behaviour of the pair: heat generated in the 40 mm bore cones flows along the shaft and changes the setting; the /DF clearance class is chosen for the catalogue speed range 5,600–8,500 r/min, so re-select the clearance class if the application runs hotter. Lubrication for the pair should be sized against the combined 39.5 mm width and 870 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.Ordering number SKF 30208/DF in SKF catalogue PUB BU/P1 17000 denotes two single-row tapered roller bearings supplied as a matched face-to-face (X) matched pair set for a 40 mm shaft — one order number, one factory setting.On the SKF nameplate, 30208-DF reads as base 30208 in a /DF matched execution — the suffix is part of the order number because a matched set is ground for a specific axial clearance and cannot be assembled from loose single bearings. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 39.5 mm overall width of 30208-DF is the axial space the pair occupies. With a pair mass of 870 g across the 40×80×39.5 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Cross-section geometry: the 20.0 mm half-section ((80−40)/2) places the roller pitch diameter near 60 mm, and the 39.5 mm axial width sets the abutment depth — geometry that fixes the contact angle behaviour of 30208-DF.", "applications": [ "industrial gearbox shafts and reducers", "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles" ], "failure_modes": [ "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "O and X arrangements are not interchangeable by turning the set around: 30208-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "Setting is built into 30208-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Replace 30208-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 130/137 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30208/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30208-DF?", "a": "The SKF 30208/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 40 mm bore, 80 mm outer diameter and 39.5 mm overall width (1.575 × 3.15 × 1.555 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 130 kN, C0 137 kN, fatigue load limit Pu 15.3 kN, reference speed 5,600 r/min, limiting speed 8,500 r/min, mass about 0.87 kg." }, { "q": "What does the /DF suffix on 30208-DF mean?", "a": "The base 30208 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 30208-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 130 kN dynamic and C0 137 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30208 table values." }, { "q": "Can 30208-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 40 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 40 mm bore." } ], "cross_ref": [ { "equiv_sku": "30208-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "30208", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30208-DF" ], "locale_variants": {}, "max_rpm": 8500, "reference_speed_rpm": 5600, "limiting_speed_rpm": 8500 }, { "sku": "31308-DF", "brand": "SKF", "manufacturer_designation": "SKF 31308/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 90, "B_mm": 50.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 156, "static_load_kN": 163, "fatigue_load_limit_kN": 19, "weight_g": 1500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Clamp the assembled pair axially through the cones — never through the rollers — and verify the 50.5 mm overall width against the catalogue value before final torquing of the shaft nut.Ordering number SKF 31308/DF in SKF catalogue PUB BU/P1 17000 denotes two single-row tapered roller bearings supplied as a matched face-to-face (X) matched pair set for a 40 mm shaft — one order number, one factory setting.Digit by digit, 31308-DF reads as the ISO 355 base bearing 31308 supplied as a face-to-face (X) matched pair matched pair (/DF); the 40 mm bore and 90 mm OD are per-bearing, the 50.5 mm width is for the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 31308-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 40 mm bore. Selection arithmetic: the catalogue C 156 kN and C0 163 kN are ratings of the complete pair, not of one bearing — never halve them back to a single-row figure when checking L10 life, and use the pair Pu 19 kN as the fatigue floor. Dimensional interchange map: within its boundary plan the 40×90×50.5 mm envelope of 31308-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Setting note for 31308-DF: the axial clearance is set at the factory by selective spacer grinding for the /DF execution; in service, re-checking end play after the first thermal cycle catches seating relaxation before it becomes roller skid.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "pump and compressor shafts" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "A matched /DF set is ground as one system: never separate the two bearings of 31308-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "Setting is built into 31308-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "O and X arrangements are not interchangeable by turning the set around: 31308-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "The 156/163 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 31308/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 31308-DF?", "a": "The SKF 31308/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 40 mm bore, 90 mm outer diameter and 50.5 mm overall width (1.575 × 3.543 × 1.988 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 156 kN, C0 163 kN, fatigue load limit Pu 19 kN, reference speed 4,500 r/min, limiting speed 7,500 r/min, mass about 1.50 kg." }, { "q": "What does the /DF suffix on 31308-DF mean?", "a": "The base 31308 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 31308-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 156 kN dynamic and C0 163 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 31308 table values." }, { "q": "Can 31308-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 40 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 40 mm bore." } ], "cross_ref": [ { "equiv_sku": "31308", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "31308-DF" ], "locale_variants": {}, "max_rpm": 7500, "reference_speed_rpm": 4500, "limiting_speed_rpm": 7500 }, { "sku": "32009X-DF", "brand": "SKF", "manufacturer_designation": "SKF 32009 X/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 75, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 123, "static_load_kN": 160, "fatigue_load_limit_kN": 17.6, "weight_g": 710, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The rotating cones of 32009X-DF take a k5 seat on the 45 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.In SKF catalogue PUB BU/P1 17000, 32009X-DF appears as SKF 32009 X/DF: a matched face-to-face (X) matched pair pair for a 45 mm shaft, rated as a set at C 123 kN and C0 160 kN.On the SKF nameplate, 32009X-DF reads as base 32009 X in a /DF matched execution — the suffix is part of the order number because a matched set is ground for a specific axial clearance and cannot be assembled from loose single bearings. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 32009X-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 45 mm bore. With a pair mass of 710 g across the 45×75×40 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Cross-section geometry: the 15.0 mm half-section ((75−45)/2) places the roller pitch diameter near 60 mm, and the 40 mm axial width sets the abutment depth — geometry that fixes the contact angle behaviour of 32009X-DF. Inspection shorthand: at overhaul, mark both bearings and the spacer of 32009X-DF before disassembly — the set is a matched system, and re-assembling with one component reversed changes the factory setting.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "belt-driven fan and blower shafts" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Clamp the 32009X-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Clamp the 32009X-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32009X-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "The 123/160 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32009 X/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32009X-DF?", "a": "The SKF 32009 X/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 45 mm bore, 75 mm outer diameter and 40 mm overall width (1.772 × 2.953 × 1.575 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 123 kN, C0 160 kN, fatigue load limit Pu 17.6 kN, reference speed 5,600 r/min, limiting speed 8,500 r/min, mass about 0.71 kg." }, { "q": "What does the /DF suffix on 32009X-DF mean?", "a": "The base 32009 X is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32009X-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 123 kN dynamic and C0 160 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32009 X table values." }, { "q": "Can 32009X-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 45 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 45 mm bore." } ], "cross_ref": [ { "equiv_sku": "32009X", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32009X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32009X-DF" ], "locale_variants": {}, "max_rpm": 8500, "reference_speed_rpm": 5600, "limiting_speed_rpm": 8500 }, { "sku": "32209-DF", "brand": "SKF", "manufacturer_designation": "SKF 32209/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 85, "B_mm": 49.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 169, "static_load_kN": 196, "fatigue_load_limit_kN": 22, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Dimensional interchange map: within its boundary plan the 45×85×49.5 mm envelope of 32209-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. When a matched /DF set like 32209-DF is replaced, replace the whole set: mixing a new bearing with a worn partner from the old set leaves the clearance and load sharing of the pair undefined. Clamp the assembled pair axially through the cones — never through the rollers — and verify the 49.5 mm overall width against the catalogue value before final torquing of the shaft nut.The SKF 32209/DF is a 45×85×49.5 mm matched tapered-roller set — two single-row bearings in face-to-face (X) matched pair arrangement, ground and shipped together with the axial clearance fixed at the factory.Numbering ties the set to its envelope: base 32209 fixes the 45 mm bore and 85 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 49.5 mm width is the combined pair dimension. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 49.5 mm overall width of 32209-DF is the axial space the pair occupies. Catalogue mass 1200 g covers both bearings and the ground spacer of 32209-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "automotive and light-truck wheel hubs" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32209-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Setting is built into 32209-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Setting is built into 32209-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "The 169/196 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32209/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32209-DF?", "a": "The SKF 32209/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 45 mm bore, 85 mm outer diameter and 49.5 mm overall width (1.772 × 3.346 × 1.949 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 169 kN, C0 196 kN, fatigue load limit Pu 22 kN, reference speed 5,300 r/min, limiting speed 8,000 r/min, mass about 1.20 kg." }, { "q": "What does the /DF suffix on 32209-DF mean?", "a": "The base 32209 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32209-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 169 kN dynamic and C0 196 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32209 table values." }, { "q": "Can 32209-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 45 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 45 mm bore." } ], "cross_ref": [ { "equiv_sku": "32209", "equiv_brand": "FAG", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32209-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32209-DF" ], "locale_variants": {}, "max_rpm": 8000, "reference_speed_rpm": 5300, "limiting_speed_rpm": 8000 }, { "sku": "31309-DF", "brand": "SKF", "manufacturer_designation": "SKF 31309/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 100, "B_mm": 54.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 194, "static_load_kN": 204, "fatigue_load_limit_kN": 24.5, "weight_g": 2000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 31309/DF belongs to the SKF matched tapered-roller range — the 45 mm bore entry in face-to-face (X) matched pair arrangement, dimensioned 100 mm OD and 54.5 mm overall width for the pair.The code breaks down as base bearing 31309 plus matched-set suffix /DF: two bearings of the 45 mm bore size, paired face-to-face (X) matched pair, with the 54.5 mm overall width spanning the whole arrangement. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 54.5 mm overall width of 31309-DF is the axial space the pair occupies. Speed planning for the set uses the catalogue pair values: 4,000 r/min thermal reference and 6,700 r/min mechanical limiting speed — a matched pair runs warmer than one bearing because two roller sets share the 54.5 mm space. Operating context for the 45 mm bore: a shaft of this diameter typically runs in the medium-bore band of industrial duty, and the 100 mm OD places the housing shoulder near 108 mm outer abutment. Mounting order matters for 31309-DF: seat the first bearing, fit the ground spacer, then the second bearing, and clamp axially as a unit — the 54.5 mm catalogue width is the assembled result and the gauge for correct assembly. A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 45 mm rotating shaft) and square abutments.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "axle-boxes in material-handling equipment" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Replace 31309-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "Clamp the 31309-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "A matched /DF set is ground as one system: never separate the two bearings of 31309-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "The 194/204 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 31309/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 31309-DF?", "a": "The SKF 31309/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 45 mm bore, 100 mm outer diameter and 54.5 mm overall width (1.772 × 3.937 × 2.146 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 194 kN, C0 204 kN, fatigue load limit Pu 24.5 kN, reference speed 4,000 r/min, limiting speed 6,700 r/min, mass about 2.00 kg." }, { "q": "What does the /DF suffix on 31309-DF mean?", "a": "The base 31309 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 31309-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 194 kN dynamic and C0 204 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 31309 table values." }, { "q": "Can 31309-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 45 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 45 mm bore." } ], "cross_ref": [ { "equiv_sku": "31309", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "31309-DF" ], "locale_variants": {}, "max_rpm": 6700, "reference_speed_rpm": 4000, "limiting_speed_rpm": 6700 }, { "sku": "30309-DF", "brand": "SKF", "manufacturer_designation": "SKF 30309/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 100, "B_mm": 54.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 227, "static_load_kN": 240, "fatigue_load_limit_kN": 28.5, "weight_g": 2000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 30309-DF appears as SKF 30309/DF: a matched face-to-face (X) matched pair pair for a 45 mm shaft, rated as a set at C 227 kN and C0 240 kN.Numbering ties the set to its envelope: base 30309 fixes the 45 mm bore and 100 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 54.5 mm width is the combined pair dimension. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 54.5 mm overall width of 30309-DF is the axial space the pair occupies. The C0/C balance of the pair is about 1.06; combined with the 28.5 kN fatigue limit this frames a set sized for reversing combined load on a 45 mm shaft rather than for pure radial duty. Material and manufacturing detail: the 2000 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class. Mounting order matters for 30309-DF: seat the first bearing, fit the ground spacer, then the second bearing, and clamp axially as a unit — the 54.5 mm catalogue width is the assembled result and the gauge for correct assembly. Lubrication for the pair should be sized against the combined 54.5 mm width and 2000 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "axle-boxes in material-handling equipment" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "O and X arrangements are not interchangeable by turning the set around: 30309-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "Setting is built into 30309-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "O and X arrangements are not interchangeable by turning the set around: 30309-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "The 227/240 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30309/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30309-DF?", "a": "The SKF 30309/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 45 mm bore, 100 mm outer diameter and 54.5 mm overall width (1.772 × 3.937 × 2.146 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 227 kN, C0 240 kN, fatigue load limit Pu 28.5 kN, reference speed 4,500 r/min, limiting speed 7,000 r/min, mass about 2.00 kg." }, { "q": "What does the /DF suffix on 30309-DF mean?", "a": "The base 30309 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 30309-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 227 kN dynamic and C0 240 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30309 table values." }, { "q": "Can 30309-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 45 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 45 mm bore." } ], "cross_ref": [ { "equiv_sku": "30309-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "30309", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30309-DF" ], "locale_variants": {}, "max_rpm": 7000, "reference_speed_rpm": 4500, "limiting_speed_rpm": 7000 }, { "sku": "32010X-DF", "brand": "SKF", "manufacturer_designation": "SKF 32010 X/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 80, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 129, "static_load_kN": 176, "fatigue_load_limit_kN": 19.3, "weight_g": 780, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 32010X-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 50 mm bore. With a pair mass of 780 g across the 50×80×40 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Assembly datum check: verify the 40 mm width against the drawing before clamping — the width is the assembled result and the quickest field check that the correct execution of 32010X-DF is on the shaft. Load sharing in 32010X-DF depends on spacer face parallelism; a cocked spacer concentrates the reversing thrust on one bearing of the pair and shows up as asymmetric raceway wear at overhaul. Lubrication for the pair should be sized against the combined 40 mm width and 780 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.In SKF catalogue PUB BU/P1 17000, 32010X-DF appears as SKF 32010 X/DF: a matched face-to-face (X) matched pair pair for a 50 mm shaft, rated as a set at C 129 kN and C0 176 kN.Numbering ties the set to its envelope: base 32010 X fixes the 50 mm bore and 80 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 40 mm width is the combined pair dimension.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "machine-tool spindles" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32010X-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32010X-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Replace 32010X-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 129/176 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32010 X/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32010X-DF?", "a": "The SKF 32010 X/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 50 mm bore, 80 mm outer diameter and 40 mm overall width (1.969 × 3.15 × 1.575 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 129 kN, C0 176 kN, fatigue load limit Pu 19.3 kN, reference speed 5,300 r/min, limiting speed 8,000 r/min, mass about 0.78 kg." }, { "q": "What does the /DF suffix on 32010X-DF mean?", "a": "The base 32010 X is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32010X-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 129 kN dynamic and C0 176 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32010 X table values." }, { "q": "Can 32010X-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 50 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 50 mm bore." } ], "cross_ref": [ { "equiv_sku": "32010X", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32010X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32010X-DF" ], "locale_variants": {}, "max_rpm": 8000, "reference_speed_rpm": 5300, "limiting_speed_rpm": 8000 }, { "sku": "33010-DF", "brand": "SKF", "manufacturer_designation": "SKF 33010/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 80, "B_mm": 48, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 145, "static_load_kN": 204, "fatigue_load_limit_kN": 22.8, "weight_g": 920, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 33010/DF belongs to the SKF matched tapered-roller range — the 50 mm bore entry in face-to-face (X) matched pair arrangement, dimensioned 80 mm OD and 48 mm overall width for the pair.The code breaks down as base bearing 33010 plus matched-set suffix /DF: two bearings of the 50 mm bore size, paired face-to-face (X) matched pair, with the 48 mm overall width spanning the whole arrangement. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 33010-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 50 mm bore. Dividing the pair C 145 kN by the 50 mm bore gives 2.90 kN per millimetre of journal for the complete arrangement — a density metric that compares matched sets across the face-to-face (X) matched pair family. Dimensional interchange map: within its boundary plan the 50×80×48 mm envelope of 33010-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Thermal behaviour of the pair: heat generated in the 50 mm bore cones flows along the shaft and changes the setting; the /DF clearance class is chosen for the catalogue speed range 5,300–8,000 r/min, so re-select the clearance class if the application runs hotter. Lubrication for the pair should be sized against the combined 48 mm width and 920 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "belt-driven fan and blower shafts" ], "failure_modes": [ "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "hard-particle indentation of the tapered raceway in unfiltered oil", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "O and X arrangements are not interchangeable by turning the set around: 33010-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "Clamp the 33010-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Replace 33010-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 145/204 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33010/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33010-DF?", "a": "The SKF 33010/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 50 mm bore, 80 mm outer diameter and 48 mm overall width (1.969 × 3.15 × 1.89 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 145 kN, C0 204 kN, fatigue load limit Pu 22.8 kN, reference speed 5,300 r/min, limiting speed 8,000 r/min, mass about 0.92 kg." }, { "q": "What does the /DF suffix on 33010-DF mean?", "a": "The base 33010 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33010-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 145 kN dynamic and C0 204 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33010 table values." }, { "q": "Can 33010-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 50 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 50 mm bore." } ], "cross_ref": [ { "equiv_sku": "33010-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "33010", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33010-DF" ], "locale_variants": {}, "max_rpm": 8000, "reference_speed_rpm": 5300, "limiting_speed_rpm": 8000 }, { "sku": "30210-DF", "brand": "SKF", "manufacturer_designation": "SKF 30210/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 90, "B_mm": 43.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 160, "static_load_kN": 183, "fatigue_load_limit_kN": 20.8, "weight_g": 1100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 30210-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 50 mm bore. Dividing the pair C 160 kN by the 50 mm bore gives 3.20 kN per millimetre of journal for the complete arrangement — a density metric that compares matched sets across the face-to-face (X) matched pair family. Operating context for the 50 mm bore: a shaft of this diameter typically runs in the medium-bore band of industrial duty, and the 90 mm OD places the housing shoulder near 98 mm outer abutment. When a matched /DF set like 30210-DF is replaced, replace the whole set: mixing a new bearing with a worn partner from the old set leaves the clearance and load sharing of the pair undefined. A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 50 mm rotating shaft) and square abutments.In SKF catalogue PUB BU/P1 17000, 30210-DF appears as SKF 30210/DF: a matched face-to-face (X) matched pair pair for a 50 mm shaft, rated as a set at C 160 kN and C0 183 kN.On the SKF nameplate, 30210-DF reads as base 30210 in a /DF matched execution — the suffix is part of the order number because a matched set is ground for a specific axial clearance and cannot be assembled from loose single bearings.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "pump and compressor shafts" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 30210-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Setting is built into 30210-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Clamp the 30210-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "The 160/183 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30210/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30210-DF?", "a": "The SKF 30210/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 50 mm bore, 90 mm outer diameter and 43.5 mm overall width (1.969 × 3.543 × 1.713 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 160 kN, C0 183 kN, fatigue load limit Pu 20.8 kN, reference speed 4,800 r/min, limiting speed 7,500 r/min, mass about 1.10 kg." }, { "q": "What does the /DF suffix on 30210-DF mean?", "a": "The base 30210 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 30210-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 160 kN dynamic and C0 183 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30210 table values." }, { "q": "Can 30210-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 50 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 50 mm bore." } ], "cross_ref": [ { "equiv_sku": "30210-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "30210", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30210-DF" ], "locale_variants": {}, "max_rpm": 7500, "reference_speed_rpm": 4800, "limiting_speed_rpm": 7500 }, { "sku": "32210-DF", "brand": "SKF", "manufacturer_designation": "SKF 32210/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 90, "B_mm": 49.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 173, "static_load_kN": 200, "fatigue_load_limit_kN": 22.8, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 32210-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 50 mm bore. Selection arithmetic: the catalogue C 173 kN and C0 200 kN are ratings of the complete pair, not of one bearing — never halve them back to a single-row figure when checking L10 life, and use the pair Pu 22.8 kN as the fatigue floor. Cross-section geometry: the 20.0 mm half-section ((90−50)/2) places the roller pitch diameter near 70 mm, and the 49.5 mm axial width sets the abutment depth — geometry that fixes the contact angle behaviour of 32210-DF. When a matched /DF set like 32210-DF is replaced, replace the whole set: mixing a new bearing with a worn partner from the old set leaves the clearance and load sharing of the pair undefined. The rotating cones of 32210-DF take a k5 seat on the 50 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.Ordering number SKF 32210/DF in SKF catalogue PUB BU/P1 17000 denotes two single-row tapered roller bearings supplied as a matched face-to-face (X) matched pair set for a 50 mm shaft — one order number, one factory setting.Numbering ties the set to its envelope: base 32210 fixes the 50 mm bore and 90 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 49.5 mm width is the combined pair dimension.", "applications": [ "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "pump and compressor shafts" ], "failure_modes": [ "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "Clamp the 32210-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32210-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32210-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "The 173/200 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32210/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32210-DF?", "a": "The SKF 32210/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 50 mm bore, 90 mm outer diameter and 49.5 mm overall width (1.969 × 3.543 × 1.949 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 173 kN, C0 200 kN, fatigue load limit Pu 22.8 kN, reference speed 4,800 r/min, limiting speed 7,500 r/min, mass about 1.30 kg." }, { "q": "What does the /DF suffix on 32210-DF mean?", "a": "The base 32210 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32210-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 173 kN dynamic and C0 200 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32210 table values." }, { "q": "Can 32210-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 50 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 50 mm bore." } ], "cross_ref": [ { "equiv_sku": "32210", "equiv_brand": "FAG", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32210-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32210-DF" ], "locale_variants": {}, "max_rpm": 7500, "reference_speed_rpm": 4800, "limiting_speed_rpm": 7500 }, { "sku": "33210-DF", "brand": "SKF", "manufacturer_designation": "SKF 33210/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 90, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 243, "static_load_kN": 320, "fatigue_load_limit_kN": 36.5, "weight_g": 1750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 33210-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 50 mm bore. The C0/C balance of the pair is about 1.32; combined with the 36.5 kN fatigue limit this frames a set sized for reversing combined load on a 50 mm shaft rather than for pure radial duty. Operating context for the 50 mm bore: a shaft of this diameter typically runs in the medium-bore band of industrial duty, and the 90 mm OD places the housing shoulder near 98 mm outer abutment. Inspection shorthand: at overhaul, mark both bearings and the spacer of 33210-DF before disassembly — the set is a matched system, and re-assembling with one component reversed changes the factory setting. A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 50 mm rotating shaft) and square abutments.SKF 33210/DF belongs to the SKF matched tapered-roller range — the 50 mm bore entry in face-to-face (X) matched pair arrangement, dimensioned 90 mm OD and 64 mm overall width for the pair.The code breaks down as base bearing 33210 plus matched-set suffix /DF: two bearings of the 50 mm bore size, paired face-to-face (X) matched pair, with the 64 mm overall width spanning the whole arrangement.", "applications": [ "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "automotive and light-truck wheel hubs", "differential and pinion drives" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 33210-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 33210-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Clamp the 33210-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "The 243/320 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33210/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33210-DF?", "a": "The SKF 33210/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 50 mm bore, 90 mm outer diameter and 64 mm overall width (1.969 × 3.543 × 2.52 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 243 kN, C0 320 kN, fatigue load limit Pu 36.5 kN, reference speed 4,800 r/min, limiting speed 7,000 r/min, mass about 1.75 kg." }, { "q": "What does the /DF suffix on 33210-DF mean?", "a": "The base 33210 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33210-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 243 kN dynamic and C0 320 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33210 table values." }, { "q": "Can 33210-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 50 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 50 mm bore." } ], "cross_ref": [ { "equiv_sku": "33210-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "33210", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33210-DF" ], "locale_variants": {}, "max_rpm": 7000, "reference_speed_rpm": 4800, "limiting_speed_rpm": 7000 }, { "sku": "31310-DF", "brand": "SKF", "manufacturer_designation": "SKF 31310/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 110, "B_mm": 58.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 224, "static_load_kN": 240, "fatigue_load_limit_kN": 28.5, "weight_g": 2550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Speed planning for the set uses the catalogue pair values: 3,600 r/min thermal reference and 6,000 r/min mechanical limiting speed — a matched pair runs warmer than one bearing because two roller sets share the 58.5 mm space. Journal and housing interface: the 50 mm bore takes a k5 shaft seat and the 110 mm outside diameter pairs with an H7 housing bore; the 58.5 mm width defines shoulder depth and the 2550 g mass is the dead load in thermal-growth calculations. Mounting order matters for 31310-DF: seat the first bearing, fit the ground spacer, then the second bearing, and clamp axially as a unit — the 58.5 mm catalogue width is the assembled result and the gauge for correct assembly. Clamp the assembled pair axially through the cones — never through the rollers — and verify the 58.5 mm overall width against the catalogue value before final torquing of the shaft nut.Ordering number SKF 31310/DF in SKF catalogue PUB BU/P1 17000 denotes two single-row tapered roller bearings supplied as a matched face-to-face (X) matched pair set for a 50 mm shaft — one order number, one factory setting.The code breaks down as base bearing 31310 plus matched-set suffix /DF: two bearings of the 50 mm bore size, paired face-to-face (X) matched pair, with the 58.5 mm overall width spanning the whole arrangement. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 58.5 mm overall width of 31310-DF is the axial space the pair occupies.", "applications": [ "differential and pinion drives", "pump and compressor shafts", "machine-tool spindles", "industrial gearbox shafts and reducers" ], "failure_modes": [ "uneven load sharing in a pair when spacer faces are not parallel to the bore", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "O and X arrangements are not interchangeable by turning the set around: 31310-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "Setting is built into 31310-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "A matched /DF set is ground as one system: never separate the two bearings of 31310-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "The 224/240 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 31310/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 31310-DF?", "a": "The SKF 31310/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 50 mm bore, 110 mm outer diameter and 58.5 mm overall width (1.969 × 4.331 × 2.303 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 224 kN, C0 240 kN, fatigue load limit Pu 28.5 kN, reference speed 3,600 r/min, limiting speed 6,000 r/min, mass about 2.55 kg." }, { "q": "What does the /DF suffix on 31310-DF mean?", "a": "The base 31310 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 31310-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 224 kN dynamic and C0 240 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 31310 table values." }, { "q": "Can 31310-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 50 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 50 mm bore." } ], "cross_ref": [ { "equiv_sku": "31310", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "31310-DF" ], "locale_variants": {}, "max_rpm": 6000, "reference_speed_rpm": 3600, "limiting_speed_rpm": 6000 }, { "sku": "32011X-DF", "brand": "SKF", "manufacturer_designation": "SKF 32011 X/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 90, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 170, "static_load_kN": 232, "fatigue_load_limit_kN": 26, "weight_g": 1150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Dividing the pair C 170 kN by the 55 mm bore gives 3.09 kN per millimetre of journal for the complete arrangement — a density metric that compares matched sets across the face-to-face (X) matched pair family. Cross-section geometry: the 17.5 mm half-section ((90−55)/2) places the roller pitch diameter near 72 mm, and the 46 mm axial width sets the abutment depth — geometry that fixes the contact angle behaviour of 32011X-DF. Thermal behaviour of the pair: heat generated in the 55 mm bore cones flows along the shaft and changes the setting; the /DF clearance class is chosen for the catalogue speed range 4,500–7,000 r/min, so re-select the clearance class if the application runs hotter. Clamp the assembled pair axially through the cones — never through the rollers — and verify the 46 mm overall width against the catalogue value before final torquing of the shaft nut.Ordering number SKF 32011 X/DF in SKF catalogue PUB BU/P1 17000 denotes two single-row tapered roller bearings supplied as a matched face-to-face (X) matched pair set for a 55 mm shaft — one order number, one factory setting.The code breaks down as base bearing 32011 X plus matched-set suffix /DF: two bearings of the 55 mm bore size, paired face-to-face (X) matched pair, with the 46 mm overall width spanning the whole arrangement. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 46 mm overall width of 32011X-DF is the axial space the pair occupies.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "differential and pinion drives" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "Setting is built into 32011X-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Setting is built into 32011X-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32011X-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "The 170/232 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32011 X/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32011X-DF?", "a": "The SKF 32011 X/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 55 mm bore, 90 mm outer diameter and 46 mm overall width (2.165 × 3.543 × 1.811 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 170 kN, C0 232 kN, fatigue load limit Pu 26 kN, reference speed 4,500 r/min, limiting speed 7,000 r/min, mass about 1.15 kg." }, { "q": "What does the /DF suffix on 32011X-DF mean?", "a": "The base 32011 X is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32011X-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 170 kN dynamic and C0 232 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32011 X table values." }, { "q": "Can 32011X-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 55 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 55 mm bore." } ], "cross_ref": [ { "equiv_sku": "32011X", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32011X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32011X-DF" ], "locale_variants": {}, "max_rpm": 7000, "reference_speed_rpm": 4500, "limiting_speed_rpm": 7000 }, { "sku": "33011-DF", "brand": "SKF", "manufacturer_designation": "SKF 33011/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 90, "B_mm": 54, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 191, "static_load_kN": 270, "fatigue_load_limit_kN": 30.5, "weight_g": 1350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The rotating cones of 33011-DF take a k5 seat on the 55 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.33011-DF is a matched pair of single-row tapered roller bearings arranged face-to-face (X) matched pair, supplied by SKF in SKF catalogue PUB BU/P1 17000 as one factory-set unit: the two bearings, spacers and setting are matched together and must not be mixed with other sets.The code breaks down as base bearing 33011 plus matched-set suffix /DF: two bearings of the 55 mm bore size, paired face-to-face (X) matched pair, with the 54 mm overall width spanning the whole arrangement. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 33011-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 55 mm bore. Catalogue mass 1350 g covers both bearings and the ground spacer of 33011-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance. Material and manufacturing detail: the 1350 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class. Spacer discipline: the spacer between the two bearings of 33011-DF is ground to the individual set — it carries a serial link to the pair, so never swap spacers between sets of the same designation.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "industrial gearbox shafts and reducers" ], "failure_modes": [ "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Setting is built into 33011-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 33011-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Replace 33011-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 191/270 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33011/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33011-DF?", "a": "The SKF 33011/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 55 mm bore, 90 mm outer diameter and 54 mm overall width (2.165 × 3.543 × 2.126 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 191 kN, C0 270 kN, fatigue load limit Pu 30.5 kN, reference speed 4,500 r/min, limiting speed 7,000 r/min, mass about 1.35 kg." }, { "q": "What does the /DF suffix on 33011-DF mean?", "a": "The base 33011 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33011-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 191 kN dynamic and C0 270 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33011 table values." }, { "q": "Can 33011-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 55 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 55 mm bore." } ], "cross_ref": [ { "equiv_sku": "33011-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "33011", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33011-DF" ], "locale_variants": {}, "max_rpm": 7000, "reference_speed_rpm": 4500, "limiting_speed_rpm": 7000 }, { "sku": "30211-DF", "brand": "SKF", "manufacturer_designation": "SKF 30211/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 100, "B_mm": 45.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 190, "static_load_kN": 212, "fatigue_load_limit_kN": 24, "weight_g": 1450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Catalogue mass 1450 g covers both bearings and the ground spacer of 30211-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance. Journal and housing interface: the 55 mm bore takes a k5 shaft seat and the 100 mm outside diameter pairs with an H7 housing bore; the 45.5 mm width defines shoulder depth and the 1450 g mass is the dead load in thermal-growth calculations. Setting note for 30211-DF: the axial clearance is set at the factory by selective spacer grinding for the /DF execution; in service, re-checking end play after the first thermal cycle catches seating relaxation before it becomes roller skid. Lubrication for the pair should be sized against the combined 45.5 mm width and 1450 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.The SKF 30211/DF is a 55×100×45.5 mm matched tapered-roller set — two single-row bearings in face-to-face (X) matched pair arrangement, ground and shipped together with the axial clearance fixed at the factory.Digit by digit, 30211-DF reads as the ISO 355 base bearing 30211 supplied as a face-to-face (X) matched pair matched pair (/DF); the 55 mm bore and 100 mm OD are per-bearing, the 45.5 mm width is for the set. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 45.5 mm overall width of 30211-DF is the axial space the pair occupies.", "applications": [ "automotive and light-truck wheel hubs", "industrial gearbox shafts and reducers", "differential and pinion drives", "axle-boxes in material-handling equipment" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Clamp the 30211-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Clamp the 30211-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Setting is built into 30211-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "The 190/212 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30211/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30211-DF?", "a": "The SKF 30211/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 55 mm bore, 100 mm outer diameter and 45.5 mm overall width (2.165 × 3.937 × 1.791 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 190 kN, C0 212 kN, fatigue load limit Pu 24 kN, reference speed 4,500 r/min, limiting speed 6,700 r/min, mass about 1.45 kg." }, { "q": "What does the /DF suffix on 30211-DF mean?", "a": "The base 30211 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 30211-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 190 kN dynamic and C0 212 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30211 table values." }, { "q": "Can 30211-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 55 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 55 mm bore." } ], "cross_ref": [ { "equiv_sku": "30211-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "30211", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30211-DF" ], "locale_variants": {}, "max_rpm": 6700, "reference_speed_rpm": 4500, "limiting_speed_rpm": 6700 }, { "sku": "32211-DF", "brand": "SKF", "manufacturer_designation": "SKF 32211/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 100, "B_mm": 53.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 222, "static_load_kN": 260, "fatigue_load_limit_kN": 30, "weight_g": 1750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Numbering ties the set to its envelope: base 32211 fixes the 55 mm bore and 100 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 53.5 mm width is the combined pair dimension. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 32211-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 55 mm bore. Speed planning for the set uses the catalogue pair values: 4,300 r/min thermal reference and 6,700 r/min mechanical limiting speed — a matched pair runs warmer than one bearing because two roller sets share the 53.5 mm space. Dimensional interchange map: within its boundary plan the 55×100×53.5 mm envelope of 32211-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Setting note for 32211-DF: the axial clearance is set at the factory by selective spacer grinding for the /DF execution; in service, re-checking end play after the first thermal cycle catches seating relaxation before it becomes roller skid. A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 55 mm rotating shaft) and square abutments.The SKF 32211/DF is a 55×100×53.5 mm matched tapered-roller set — two single-row bearings in face-to-face (X) matched pair arrangement, ground and shipped together with the axial clearance fixed at the factory.", "applications": [ "machine-tool spindles", "belt-driven fan and blower shafts", "axle-boxes in material-handling equipment", "axle-boxes in material-handling equipment" ], "failure_modes": [ "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "O and X arrangements are not interchangeable by turning the set around: 32211-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "Setting is built into 32211-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32211-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "The 222/260 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32211/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32211-DF?", "a": "The SKF 32211/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 55 mm bore, 100 mm outer diameter and 53.5 mm overall width (2.165 × 3.937 × 2.106 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 222 kN, C0 260 kN, fatigue load limit Pu 30 kN, reference speed 4,300 r/min, limiting speed 6,700 r/min, mass about 1.75 kg." }, { "q": "What does the /DF suffix on 32211-DF mean?", "a": "The base 32211 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32211-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 222 kN dynamic and C0 260 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32211 table values." }, { "q": "Can 32211-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 55 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 55 mm bore." } ], "cross_ref": [ { "equiv_sku": "32211", "equiv_brand": "FAG", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32211-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32211-DF" ], "locale_variants": {}, "max_rpm": 6700, "reference_speed_rpm": 4300, "limiting_speed_rpm": 6700 }, { "sku": "31311-DF", "brand": "SKF", "manufacturer_designation": "SKF 31311/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 120, "B_mm": 63, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 256, "static_load_kN": 275, "fatigue_load_limit_kN": 33.5, "weight_g": 3250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Material and manufacturing detail: the 3250 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class. Inspection shorthand: at overhaul, mark both bearings and the spacer of 31311-DF before disassembly — the set is a matched system, and re-assembling with one component reversed changes the factory setting. A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 55 mm rotating shaft) and square abutments.SKF 31311/DF belongs to the SKF matched tapered-roller range — the 55 mm bore entry in face-to-face (X) matched pair arrangement, dimensioned 120 mm OD and 63 mm overall width for the pair.Numbering ties the set to its envelope: base 31311 fixes the 55 mm bore and 120 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 63 mm width is the combined pair dimension. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 31311-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 55 mm bore. With a pair mass of 3250 g across the 55×120×63 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "machine-tool spindles" ], "failure_modes": [ "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "A matched /DF set is ground as one system: never separate the two bearings of 31311-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "Clamp the 31311-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Replace 31311-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 256/275 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 31311/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 31311-DF?", "a": "The SKF 31311/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 55 mm bore, 120 mm outer diameter and 63 mm overall width (2.165 × 4.724 × 2.48 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 256 kN, C0 275 kN, fatigue load limit Pu 33.5 kN, reference speed 3,400 r/min, limiting speed 5,600 r/min, mass about 3.25 kg." }, { "q": "What does the /DF suffix on 31311-DF mean?", "a": "The base 31311 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 31311-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 256 kN dynamic and C0 275 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 31311 table values." }, { "q": "Can 31311-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 55 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 55 mm bore." } ], "cross_ref": [ { "equiv_sku": "31311", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "31311-DF" ], "locale_variants": {}, "max_rpm": 5600, "reference_speed_rpm": 3400, "limiting_speed_rpm": 5600 }, { "sku": "30311-DF", "brand": "SKF", "manufacturer_designation": "SKF 30311/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 120, "B_mm": 63, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 302, "static_load_kN": 325, "fatigue_load_limit_kN": 39, "weight_g": 3250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Load system: C 302 kN against C0 325 kN gives a 1.08 balance, and 5.49 kN of dynamic capacity per millimetre of the 55 mm bore is the density figure to compare against neighbouring sizes. Inspection shorthand: at overhaul, mark both bearings and the spacer of 30311-DF before disassembly — the set is a matched system, and re-assembling with one component reversed changes the factory setting. Lubrication for the pair should be sized against the combined 63 mm width and 3250 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.In SKF catalogue PUB BU/P1 17000, 30311-DF appears as SKF 30311/DF: a matched face-to-face (X) matched pair pair for a 55 mm shaft, rated as a set at C 302 kN and C0 325 kN.Reading the designation: 30311 is the ISO 355 single-row base bearing (55 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 55×120×63 mm; the width covers both bearings of the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 30311-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 55 mm bore. Dividing the pair C 302 kN by the 55 mm bore gives 5.49 kN per millimetre of journal for the complete arrangement — a density metric that compares matched sets across the face-to-face (X) matched pair family.", "applications": [ "pump and compressor shafts", "machine-tool spindles", "belt-driven fan and blower shafts", "machine-tool spindles" ], "failure_modes": [ "roller large-end smearing against the cone rib after EP lubricant film failure", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Replace 30311-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "Setting is built into 30311-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "A matched /DF set is ground as one system: never separate the two bearings of 30311-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "The 302/325 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30311/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30311-DF?", "a": "The SKF 30311/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 55 mm bore, 120 mm outer diameter and 63 mm overall width (2.165 × 4.724 × 2.48 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 302 kN, C0 325 kN, fatigue load limit Pu 39 kN, reference speed 3,800 r/min, limiting speed 5,600 r/min, mass about 3.25 kg." }, { "q": "What does the /DF suffix on 30311-DF mean?", "a": "The base 30311 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 30311-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 302 kN dynamic and C0 325 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30311 table values." }, { "q": "Can 30311-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 55 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 55 mm bore." } ], "cross_ref": [ { "equiv_sku": "30311-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "30311", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30311-DF" ], "locale_variants": {}, "max_rpm": 5600, "reference_speed_rpm": 3800, "limiting_speed_rpm": 5600 }, { "sku": "32012X-DF", "brand": "SKF", "manufacturer_designation": "SKF 32012 X/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 95, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 173, "static_load_kN": 245, "fatigue_load_limit_kN": 27, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Assembly datum check: verify the 46 mm width against the drawing before clamping — the width is the assembled result and the quickest field check that the correct execution of 32012X-DF is on the shaft. When a matched /DF set like 32012X-DF is replaced, replace the whole set: mixing a new bearing with a worn partner from the old set leaves the clearance and load sharing of the pair undefined. A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 60 mm rotating shaft) and square abutments.Ordering number SKF 32012 X/DF in SKF catalogue PUB BU/P1 17000 denotes two single-row tapered roller bearings supplied as a matched face-to-face (X) matched pair set for a 60 mm shaft — one order number, one factory setting.Digit by digit, 32012X-DF reads as the ISO 355 base bearing 32012 X supplied as a face-to-face (X) matched pair matched pair (/DF); the 60 mm bore and 95 mm OD are per-bearing, the 46 mm width is for the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 32012X-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 60 mm bore. Selection arithmetic: the catalogue C 173 kN and C0 245 kN are ratings of the complete pair, not of one bearing — never halve them back to a single-row figure when checking L10 life, and use the pair Pu 27 kN as the fatigue floor.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "Clamp the 32012X-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Clamp the 32012X-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Setting is built into 32012X-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "The 173/245 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32012 X/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32012X-DF?", "a": "The SKF 32012 X/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 60 mm bore, 95 mm outer diameter and 46 mm overall width (2.362 × 3.74 × 1.811 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 173 kN, C0 245 kN, fatigue load limit Pu 27 kN, reference speed 4,300 r/min, limiting speed 6,700 r/min, mass about 1.20 kg." }, { "q": "What does the /DF suffix on 32012X-DF mean?", "a": "The base 32012 X is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32012X-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 173 kN dynamic and C0 245 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32012 X table values." }, { "q": "Can 32012X-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 60 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 60 mm bore." } ], "cross_ref": [ { "equiv_sku": "32012X", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32012X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32012X-DF" ], "locale_variants": {}, "max_rpm": 6700, "reference_speed_rpm": 4300, "limiting_speed_rpm": 6700 }, { "sku": "30212-DF", "brand": "SKF", "manufacturer_designation": "SKF 30212/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 110, "B_mm": 47.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 207, "static_load_kN": 228, "fatigue_load_limit_kN": 26.5, "weight_g": 1800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 47.5 mm overall width of 30212-DF is the axial space the pair occupies. Selection arithmetic: the catalogue C 207 kN and C0 228 kN are ratings of the complete pair, not of one bearing — never halve them back to a single-row figure when checking L10 life, and use the pair Pu 26.5 kN as the fatigue floor. Load system: C 207 kN against C0 228 kN gives a 1.10 balance, and 3.45 kN of dynamic capacity per millimetre of the 60 mm bore is the density figure to compare against neighbouring sizes. Mounting order matters for 30212-DF: seat the first bearing, fit the ground spacer, then the second bearing, and clamp axially as a unit — the 47.5 mm catalogue width is the assembled result and the gauge for correct assembly. The rotating cones of 30212-DF take a k5 seat on the 60 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.30212-DF (SKF 30212/DF) is the face-to-face (X) matched pair matched-set choice for a 60 mm shaft: a pair of tapered roller bearings whose combined envelope is 110×47.5 mm, delivered ready to mount with controlled internal clearance.Digit by digit, 30212-DF reads as the ISO 355 base bearing 30212 supplied as a face-to-face (X) matched pair matched pair (/DF); the 60 mm bore and 110 mm OD are per-bearing, the 47.5 mm width is for the set.", "applications": [ "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "rolling-mill auxiliary drives" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "O and X arrangements are not interchangeable by turning the set around: 30212-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 30212-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Setting is built into 30212-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "The 207/228 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30212/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30212-DF?", "a": "The SKF 30212/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 60 mm bore, 110 mm outer diameter and 47.5 mm overall width (2.362 × 4.331 × 1.87 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 207 kN, C0 228 kN, fatigue load limit Pu 26.5 kN, reference speed 4,000 r/min, limiting speed 6,000 r/min, mass about 1.80 kg." }, { "q": "What does the /DF suffix on 30212-DF mean?", "a": "The base 30212 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 30212-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 207 kN dynamic and C0 228 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30212 table values." }, { "q": "Can 30212-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 60 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 60 mm bore." } ], "cross_ref": [ { "equiv_sku": "30212-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "30212", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30212-DF" ], "locale_variants": {}, "max_rpm": 6000, "reference_speed_rpm": 4000, "limiting_speed_rpm": 6000 }, { "sku": "32212-DF", "brand": "SKF", "manufacturer_designation": "SKF 32212/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 110, "B_mm": 59.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 266, "static_load_kN": 320, "fatigue_load_limit_kN": 37.5, "weight_g": 2400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 59.5 mm overall width of 32212-DF is the axial space the pair occupies. Speed planning for the set uses the catalogue pair values: 4,000 r/min thermal reference and 6,000 r/min mechanical limiting speed — a matched pair runs warmer than one bearing because two roller sets share the 59.5 mm space. Material and manufacturing detail: the 2400 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class. Load sharing in 32212-DF depends on spacer face parallelism; a cocked spacer concentrates the reversing thrust on one bearing of the pair and shows up as asymmetric raceway wear at overhaul. Lubrication for the pair should be sized against the combined 59.5 mm width and 2400 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.32212-DF is a matched pair of single-row tapered roller bearings arranged face-to-face (X) matched pair, supplied by SKF in SKF catalogue PUB BU/P1 17000 as one factory-set unit: the two bearings, spacers and setting are matched together and must not be mixed with other sets.Reading the designation: 32212 is the ISO 355 single-row base bearing (60 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 60×110×59.5 mm; the width covers both bearings of the set.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "large process pump and compressor shafts" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "A matched /DF set is ground as one system: never separate the two bearings of 32212-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "Setting is built into 32212-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "O and X arrangements are not interchangeable by turning the set around: 32212-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "The 266/320 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32212/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32212-DF?", "a": "The SKF 32212/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 60 mm bore, 110 mm outer diameter and 59.5 mm overall width (2.362 × 4.331 × 2.343 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 266 kN, C0 320 kN, fatigue load limit Pu 37.5 kN, reference speed 4,000 r/min, limiting speed 6,000 r/min, mass about 2.40 kg." }, { "q": "What does the /DF suffix on 32212-DF mean?", "a": "The base 32212 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32212-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 266 kN dynamic and C0 320 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32212 table values." }, { "q": "Can 32212-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 60 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 60 mm bore." } ], "cross_ref": [ { "equiv_sku": "32212", "equiv_brand": "FAG", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32212-DF" ], "locale_variants": {}, "max_rpm": 6000, "reference_speed_rpm": 4000, "limiting_speed_rpm": 6000 }, { "sku": "33212-DF", "brand": "SKF", "manufacturer_designation": "SKF 33212/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 110, "B_mm": 76, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 354, "static_load_kN": 475, "fatigue_load_limit_kN": 53, "weight_g": 3150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF 33212/DF in SKF catalogue PUB BU/P1 17000 denotes two single-row tapered roller bearings supplied as a matched face-to-face (X) matched pair set for a 60 mm shaft — one order number, one factory setting.The code breaks down as base bearing 33212 plus matched-set suffix /DF: two bearings of the 60 mm bore size, paired face-to-face (X) matched pair, with the 76 mm overall width spanning the whole arrangement. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 33212-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 60 mm bore. Selection arithmetic: the catalogue C 354 kN and C0 475 kN are ratings of the complete pair, not of one bearing — never halve them back to a single-row figure when checking L10 life, and use the pair Pu 53 kN as the fatigue floor. Load system: C 354 kN against C0 475 kN gives a 1.34 balance, and 5.90 kN of dynamic capacity per millimetre of the 60 mm bore is the density figure to compare against neighbouring sizes. Inspection shorthand: at overhaul, mark both bearings and the spacer of 33212-DF before disassembly — the set is a matched system, and re-assembling with one component reversed changes the factory setting. Clamp the assembled pair axially through the cones — never through the rollers — and verify the 76 mm overall width against the catalogue value before final torquing of the shaft nut.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "rolling-mill auxiliary drives" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "Clamp the 33212-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 33212-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Replace 33212-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 354/475 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33212/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33212-DF?", "a": "The SKF 33212/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 60 mm bore, 110 mm outer diameter and 76 mm overall width (2.362 × 4.331 × 2.992 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 354 kN, C0 475 kN, fatigue load limit Pu 53 kN, reference speed 3,800 r/min, limiting speed 6,000 r/min, mass about 3.15 kg." }, { "q": "What does the /DF suffix on 33212-DF mean?", "a": "The base 33212 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33212-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 354 kN dynamic and C0 475 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33212 table values." }, { "q": "Can 33212-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 60 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 60 mm bore." } ], "cross_ref": [ { "equiv_sku": "33212", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33212-DF" ], "locale_variants": {}, "max_rpm": 6000, "reference_speed_rpm": 3800, "limiting_speed_rpm": 6000 }, { "sku": "31312-DF", "brand": "SKF", "manufacturer_designation": "SKF 31312/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 130, "B_mm": 67, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 303, "static_load_kN": 335, "fatigue_load_limit_kN": 40.5, "weight_g": 4050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The C0/C balance of the pair is about 1.11; combined with the 40.5 kN fatigue limit this frames a set sized for reversing combined load on a 60 mm shaft rather than for pure radial duty. Assembly datum check: verify the 67 mm width against the drawing before clamping — the width is the assembled result and the quickest field check that the correct execution of 31312-DF is on the shaft. Load sharing in 31312-DF depends on spacer face parallelism; a cocked spacer concentrates the reversing thrust on one bearing of the pair and shows up as asymmetric raceway wear at overhaul. Do not separate 31312-DF into single-bearing service stock — as individual bearings the components are not interchangeable with catalogue single-row executions because the rings are ground for the set.31312-DF is a matched pair of single-row tapered roller bearings arranged face-to-face (X) matched pair, supplied by SKF in SKF catalogue PUB BU/P1 17000 as one factory-set unit: the two bearings, spacers and setting are matched together and must not be mixed with other sets.Numbering ties the set to its envelope: base 31312 fixes the 60 mm bore and 130 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 67 mm width is the combined pair dimension. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 31312-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 60 mm bore.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 31312-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 31312-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Replace 31312-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 303/335 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 31312/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 31312-DF?", "a": "The SKF 31312/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 60 mm bore, 130 mm outer diameter and 67 mm overall width (2.362 × 5.118 × 2.638 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 303 kN, C0 335 kN, fatigue load limit Pu 40.5 kN, reference speed 3,000 r/min, limiting speed 5,300 r/min, mass about 4.05 kg." }, { "q": "What does the /DF suffix on 31312-DF mean?", "a": "The base 31312 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 31312-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 303 kN dynamic and C0 335 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 31312 table values." }, { "q": "Can 31312-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 60 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 60 mm bore." } ], "cross_ref": [ { "equiv_sku": "31312", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "31312-DF" ], "locale_variants": {}, "max_rpm": 5300, "reference_speed_rpm": 3000, "limiting_speed_rpm": 5300 }, { "sku": "30312-DF", "brand": "SKF", "manufacturer_designation": "SKF 30312/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 130, "B_mm": 67, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 357, "static_load_kN": 390, "fatigue_load_limit_kN": 47.5, "weight_g": 4100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Catalogue mass 4100 g covers both bearings and the ground spacer of 30312-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance. Operating context for the 60 mm bore: a shaft of this diameter typically runs in the large-bore band of industrial duty, and the 130 mm OD places the housing shoulder near 138 mm outer abutment. Load sharing in 30312-DF depends on spacer face parallelism; a cocked spacer concentrates the reversing thrust on one bearing of the pair and shows up as asymmetric raceway wear at overhaul. The rotating cones of 30312-DF take a k5 seat on the 60 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.For a 60 mm shaft carrying reversing axial load, SKF lists 30312-DF under catalogue execution SKF 30312/DF: a factory-matched face-to-face (X) matched pair tapered-roller pair, set and measured as one unit.Reading the designation: 30312 is the ISO 355 single-row base bearing (60 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 60×130×67 mm; the width covers both bearings of the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 30312-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 60 mm bore.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "roller large-end smearing against the cone rib after EP lubricant film failure", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Clamp the 30312-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Clamp the 30312-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "A matched /DF set is ground as one system: never separate the two bearings of 30312-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "The 357/390 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30312/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30312-DF?", "a": "The SKF 30312/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 60 mm bore, 130 mm outer diameter and 67 mm overall width (2.362 × 5.118 × 2.638 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 357 kN, C0 390 kN, fatigue load limit Pu 47.5 kN, reference speed 3,600 r/min, limiting speed 5,300 r/min, mass about 4.10 kg." }, { "q": "What does the /DF suffix on 30312-DF mean?", "a": "The base 30312 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 30312-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 357 kN dynamic and C0 390 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30312 table values." }, { "q": "Can 30312-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 60 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 60 mm bore." } ], "cross_ref": [ { "equiv_sku": "30312", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30312-DF" ], "locale_variants": {}, "max_rpm": 5300, "reference_speed_rpm": 3600, "limiting_speed_rpm": 5300 }, { "sku": "32312-DF", "brand": "SKF", "manufacturer_designation": "SKF 32312/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 130, "B_mm": 97, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 483, "static_load_kN": 585, "fatigue_load_limit_kN": 68, "weight_g": 6050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Speed planning for the set uses the catalogue pair values: 3,200 r/min thermal reference and 5,300 r/min mechanical limiting speed — a matched pair runs warmer than one bearing because two roller sets share the 97 mm space. Operating context for the 60 mm bore: a shaft of this diameter typically runs in the large-bore band of industrial duty, and the 130 mm OD places the housing shoulder near 138 mm outer abutment. Thermal behaviour of the pair: heat generated in the 60 mm bore cones flows along the shaft and changes the setting; the /DF clearance class is chosen for the catalogue speed range 3,200–5,300 r/min, so re-select the clearance class if the application runs hotter. Clamp the assembled pair axially through the cones — never through the rollers — and verify the 97 mm overall width against the catalogue value before final torquing of the shaft nut.For a 60 mm shaft carrying reversing axial load, SKF lists 32312-DF under catalogue execution SKF 32312/DF: a factory-matched face-to-face (X) matched pair tapered-roller pair, set and measured as one unit.The code breaks down as base bearing 32312 plus matched-set suffix /DF: two bearings of the 60 mm bore size, paired face-to-face (X) matched pair, with the 97 mm overall width spanning the whole arrangement. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 32312-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 60 mm bore.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Setting is built into 32312-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Setting is built into 32312-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Clamp the 32312-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "The 483/585 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32312/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32312-DF?", "a": "The SKF 32312/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 60 mm bore, 130 mm outer diameter and 97 mm overall width (2.362 × 5.118 × 3.819 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 483 kN, C0 585 kN, fatigue load limit Pu 68 kN, reference speed 3,200 r/min, limiting speed 5,300 r/min, mass about 6.05 kg." }, { "q": "What does the /DF suffix on 32312-DF mean?", "a": "The base 32312 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32312-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 483 kN dynamic and C0 585 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32312 table values." }, { "q": "Can 32312-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 60 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 60 mm bore." } ], "cross_ref": [ { "equiv_sku": "32312", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32312-DF" ], "locale_variants": {}, "max_rpm": 5300, "reference_speed_rpm": 3200, "limiting_speed_rpm": 5300 }, { "sku": "32013X-DF", "brand": "SKF", "manufacturer_designation": "SKF 32013 X/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 100, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 176, "static_load_kN": 255, "fatigue_load_limit_kN": 28, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Setting note for 32013X-DF: the axial clearance is set at the factory by selective spacer grinding for the /DF execution; in service, re-checking end play after the first thermal cycle catches seating relaxation before it becomes roller skid. The rotating cones of 32013X-DF take a k5 seat on the 65 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.For a 65 mm shaft carrying reversing axial load, SKF lists 32013X-DF under catalogue execution SKF 32013 X/DF: a factory-matched face-to-face (X) matched pair tapered-roller pair, set and measured as one unit.On the SKF nameplate, 32013X-DF reads as base 32013 X in a /DF matched execution — the suffix is part of the order number because a matched set is ground for a specific axial clearance and cannot be assembled from loose single bearings. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 46 mm overall width of 32013X-DF is the axial space the pair occupies. With a pair mass of 1300 g across the 65×100×46 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Cross-section geometry: the 17.5 mm half-section ((100−65)/2) places the roller pitch diameter near 82 mm, and the 46 mm axial width sets the abutment depth — geometry that fixes the contact angle behaviour of 32013X-DF.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32013X-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32013X-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "O and X arrangements are not interchangeable by turning the set around: 32013X-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "The 176/255 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32013 X/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32013X-DF?", "a": "The SKF 32013 X/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 65 mm bore, 100 mm outer diameter and 46 mm overall width (2.559 × 3.937 × 1.811 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 176 kN, C0 255 kN, fatigue load limit Pu 28 kN, reference speed 4,000 r/min, limiting speed 6,000 r/min, mass about 1.30 kg." }, { "q": "What does the /DF suffix on 32013X-DF mean?", "a": "The base 32013 X is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32013X-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 176 kN dynamic and C0 255 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32013 X table values." }, { "q": "Can 32013X-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 65 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 65 mm bore." } ], "cross_ref": [ { "equiv_sku": "32013X", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32013X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32013X-DF" ], "locale_variants": {}, "max_rpm": 6000, "reference_speed_rpm": 4000, "limiting_speed_rpm": 6000 }, { "sku": "33013-DF", "brand": "SKF", "manufacturer_designation": "SKF 33013/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 100, "B_mm": 54, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 204, "static_load_kN": 310, "fatigue_load_limit_kN": 34.5, "weight_g": 1550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Lubrication for the pair should be sized against the combined 54 mm width and 1550 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.SKF 33013/DF belongs to the SKF matched tapered-roller range — the 65 mm bore entry in face-to-face (X) matched pair arrangement, dimensioned 100 mm OD and 54 mm overall width for the pair.Numbering ties the set to its envelope: base 33013 fixes the 65 mm bore and 100 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 54 mm width is the combined pair dimension. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 54 mm overall width of 33013-DF is the axial space the pair occupies. Speed planning for the set uses the catalogue pair values: 4,000 r/min thermal reference and 6,300 r/min mechanical limiting speed — a matched pair runs warmer than one bearing because two roller sets share the 54 mm space. Dimensional interchange map: within its boundary plan the 65×100×54 mm envelope of 33013-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Setting note for 33013-DF: the axial clearance is set at the factory by selective spacer grinding for the /DF execution; in service, re-checking end play after the first thermal cycle catches seating relaxation before it becomes roller skid.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Replace 33013-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "Clamp the 33013-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "O and X arrangements are not interchangeable by turning the set around: 33013-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "The 204/310 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33013/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33013-DF?", "a": "The SKF 33013/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 65 mm bore, 100 mm outer diameter and 54 mm overall width (2.559 × 3.937 × 2.126 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 204 kN, C0 310 kN, fatigue load limit Pu 34.5 kN, reference speed 4,000 r/min, limiting speed 6,300 r/min, mass about 1.55 kg." }, { "q": "What does the /DF suffix on 33013-DF mean?", "a": "The base 33013 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33013-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 204 kN dynamic and C0 310 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33013 table values." }, { "q": "Can 33013-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 65 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 65 mm bore." } ], "cross_ref": [ { "equiv_sku": "33013-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "33013", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33013-DF" ], "locale_variants": {}, "max_rpm": 6300, "reference_speed_rpm": 4000, "limiting_speed_rpm": 6300 }, { "sku": "30213-DF", "brand": "SKF", "manufacturer_designation": "SKF 30213/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 120, "B_mm": 49.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 242, "static_load_kN": 270, "fatigue_load_limit_kN": 32.5, "weight_g": 2300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Catalogue mass 2300 g covers both bearings and the ground spacer of 30213-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance. Material and manufacturing detail: the 2300 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class. Thermal behaviour of the pair: heat generated in the 65 mm bore cones flows along the shaft and changes the setting; the /DF clearance class is chosen for the catalogue speed range 3,600–5,600 r/min, so re-select the clearance class if the application runs hotter. The rotating cones of 30213-DF take a k5 seat on the 65 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.Ordering number SKF 30213/DF in SKF catalogue PUB BU/P1 17000 denotes two single-row tapered roller bearings supplied as a matched face-to-face (X) matched pair set for a 65 mm shaft — one order number, one factory setting.Numbering ties the set to its envelope: base 30213 fixes the 65 mm bore and 120 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 49.5 mm width is the combined pair dimension. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 30213-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 65 mm bore.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "crane sheave and hoist gearboxes" ], "failure_modes": [ "roller large-end smearing against the cone rib after EP lubricant film failure", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 30213-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 30213-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Replace 30213-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 242/270 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30213/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30213-DF?", "a": "The SKF 30213/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 65 mm bore, 120 mm outer diameter and 49.5 mm overall width (2.559 × 4.724 × 1.949 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 242 kN, C0 270 kN, fatigue load limit Pu 32.5 kN, reference speed 3,600 r/min, limiting speed 5,600 r/min, mass about 2.30 kg." }, { "q": "What does the /DF suffix on 30213-DF mean?", "a": "The base 30213 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 30213-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 242 kN dynamic and C0 270 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30213 table values." }, { "q": "Can 30213-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 65 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 65 mm bore." } ], "cross_ref": [ { "equiv_sku": "30213-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "30213", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30213-DF" ], "locale_variants": {}, "max_rpm": 5600, "reference_speed_rpm": 3600, "limiting_speed_rpm": 5600 }, { "sku": "32213-DF", "brand": "SKF", "manufacturer_designation": "SKF 32213/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 120, "B_mm": 65.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 320, "static_load_kN": 390, "fatigue_load_limit_kN": 45.5, "weight_g": 3100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Reading the designation: 32213 is the ISO 355 single-row base bearing (65 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 65×120×65.5 mm; the width covers both bearings of the set. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 65.5 mm overall width of 32213-DF is the axial space the pair occupies. The C0/C balance of the pair is about 1.22; combined with the 45.5 kN fatigue limit this frames a set sized for reversing combined load on a 65 mm shaft rather than for pure radial duty. Cross-section geometry: the 27.5 mm half-section ((120−65)/2) places the roller pitch diameter near 92 mm, and the 65.5 mm axial width sets the abutment depth — geometry that fixes the contact angle behaviour of 32213-DF. Inspection shorthand: at overhaul, mark both bearings and the spacer of 32213-DF before disassembly — the set is a matched system, and re-assembling with one component reversed changes the factory setting. The rotating cones of 32213-DF take a k5 seat on the 65 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.Ordering number SKF 32213/DF in SKF catalogue PUB BU/P1 17000 denotes two single-row tapered roller bearings supplied as a matched face-to-face (X) matched pair set for a 65 mm shaft — one order number, one factory setting.", "applications": [ "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives", "construction machinery drives" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32213-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32213-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Clamp the 32213-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "The 320/390 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32213/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32213-DF?", "a": "The SKF 32213/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 65 mm bore, 120 mm outer diameter and 65.5 mm overall width (2.559 × 4.724 × 2.579 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 320 kN, C0 390 kN, fatigue load limit Pu 45.5 kN, reference speed 3,600 r/min, limiting speed 5,600 r/min, mass about 3.10 kg." }, { "q": "What does the /DF suffix on 32213-DF mean?", "a": "The base 32213 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32213-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 320 kN dynamic and C0 390 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32213 table values." }, { "q": "Can 32213-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 65 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 65 mm bore." } ], "cross_ref": [ { "equiv_sku": "32213", "equiv_brand": "FAG", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32213-DF" ], "locale_variants": {}, "max_rpm": 5600, "reference_speed_rpm": 3600, "limiting_speed_rpm": 5600 }, { "sku": "31313-DF", "brand": "SKF", "manufacturer_designation": "SKF 31313/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 140, "B_mm": 72, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 348, "static_load_kN": 380, "fatigue_load_limit_kN": 47.5, "weight_g": 5000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 31313-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 65 mm bore. Dividing the pair C 348 kN by the 65 mm bore gives 5.35 kN per millimetre of journal for the complete arrangement — a density metric that compares matched sets across the face-to-face (X) matched pair family. Journal and housing interface: the 65 mm bore takes a k5 shaft seat and the 140 mm outside diameter pairs with an H7 housing bore; the 72 mm width defines shoulder depth and the 5000 g mass is the dead load in thermal-growth calculations. Thermal behaviour of the pair: heat generated in the 65 mm bore cones flows along the shaft and changes the setting; the /DF clearance class is chosen for the catalogue speed range 2,800–4,800 r/min, so re-select the clearance class if the application runs hotter. Clamp the assembled pair axially through the cones — never through the rollers — and verify the 72 mm overall width against the catalogue value before final torquing of the shaft nut.Ordering number SKF 31313/DF in SKF catalogue PUB BU/P1 17000 denotes two single-row tapered roller bearings supplied as a matched face-to-face (X) matched pair set for a 65 mm shaft — one order number, one factory setting.Numbering ties the set to its envelope: base 31313 fixes the 65 mm bore and 140 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 72 mm width is the combined pair dimension.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "crane sheave and hoist gearboxes" ], "failure_modes": [ "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Replace 31313-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "Setting is built into 31313-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Replace 31313-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 348/380 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 31313/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 31313-DF?", "a": "The SKF 31313/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 65 mm bore, 140 mm outer diameter and 72 mm overall width (2.559 × 5.512 × 2.835 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 348 kN, C0 380 kN, fatigue load limit Pu 47.5 kN, reference speed 2,800 r/min, limiting speed 4,800 r/min, mass about 5.00 kg." }, { "q": "What does the /DF suffix on 31313-DF mean?", "a": "The base 31313 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 31313-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 348 kN dynamic and C0 380 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 31313 table values." }, { "q": "Can 31313-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 65 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 65 mm bore." } ], "cross_ref": [ { "equiv_sku": "31313", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "31313-DF" ], "locale_variants": {}, "max_rpm": 4800, "reference_speed_rpm": 2800, "limiting_speed_rpm": 4800 }, { "sku": "32014X-DF", "brand": "SKF", "manufacturer_designation": "SKF 32014 X/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 110, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 214, "static_load_kN": 305, "fatigue_load_limit_kN": 34.5, "weight_g": 1750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Clamp the assembled pair axially through the cones — never through the rollers — and verify the 50 mm overall width against the catalogue value before final torquing of the shaft nut.For a 70 mm shaft carrying reversing axial load, SKF lists 32014X-DF under catalogue execution SKF 32014 X/DF: a factory-matched face-to-face (X) matched pair tapered-roller pair, set and measured as one unit.Reading the designation: 32014 X is the ISO 355 single-row base bearing (70 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 70×110×50 mm; the width covers both bearings of the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 32014X-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 70 mm bore. Dividing the pair C 214 kN by the 70 mm bore gives 3.06 kN per millimetre of journal for the complete arrangement — a density metric that compares matched sets across the face-to-face (X) matched pair family. Assembly datum check: verify the 50 mm width against the drawing before clamping — the width is the assembled result and the quickest field check that the correct execution of 32014X-DF is on the shaft. Inspection shorthand: at overhaul, mark both bearings and the spacer of 32014X-DF before disassembly — the set is a matched system, and re-assembling with one component reversed changes the factory setting.", "applications": [ "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "crane sheave and hoist gearboxes" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Setting is built into 32014X-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Setting is built into 32014X-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Replace 32014X-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 214/305 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32014 X/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32014X-DF?", "a": "The SKF 32014 X/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 70 mm bore, 110 mm outer diameter and 50 mm overall width (2.756 × 4.331 × 1.969 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 214 kN, C0 305 kN, fatigue load limit Pu 34.5 kN, reference speed 3,800 r/min, limiting speed 5,600 r/min, mass about 1.75 kg." }, { "q": "What does the /DF suffix on 32014X-DF mean?", "a": "The base 32014 X is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32014X-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 214 kN dynamic and C0 305 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32014 X table values." }, { "q": "Can 32014X-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 70 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 70 mm bore." } ], "cross_ref": [ { "equiv_sku": "32014X", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32014X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32014X-DF" ], "locale_variants": {}, "max_rpm": 5600, "reference_speed_rpm": 3800, "limiting_speed_rpm": 5600 }, { "sku": "33014-DF", "brand": "SKF", "manufacturer_designation": "SKF 33014/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 110, "B_mm": 62, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 273, "static_load_kN": 400, "fatigue_load_limit_kN": 45.5, "weight_g": 2200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Mounting order matters for 33014-DF: seat the first bearing, fit the ground spacer, then the second bearing, and clamp axially as a unit — the 62 mm catalogue width is the assembled result and the gauge for correct assembly. The rotating cones of 33014-DF take a k5 seat on the 70 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.33014-DF is a matched pair of single-row tapered roller bearings arranged face-to-face (X) matched pair, supplied by SKF in SKF catalogue PUB BU/P1 17000 as one factory-set unit: the two bearings, spacers and setting are matched together and must not be mixed with other sets.Numbering ties the set to its envelope: base 33014 fixes the 70 mm bore and 110 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 62 mm width is the combined pair dimension. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 62 mm overall width of 33014-DF is the axial space the pair occupies. With a pair mass of 2200 g across the 70×110×62 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Material and manufacturing detail: the 2200 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "Clamp the 33014-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 33014-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "O and X arrangements are not interchangeable by turning the set around: 33014-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "The 273/400 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33014/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33014-DF?", "a": "The SKF 33014/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 70 mm bore, 110 mm outer diameter and 62 mm overall width (2.756 × 4.331 × 2.441 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 273 kN, C0 400 kN, fatigue load limit Pu 45.5 kN, reference speed 3,800 r/min, limiting speed 5,600 r/min, mass about 2.20 kg." }, { "q": "What does the /DF suffix on 33014-DF mean?", "a": "The base 33014 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33014-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 273 kN dynamic and C0 400 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33014 table values." }, { "q": "Can 33014-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 70 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 70 mm bore." } ], "cross_ref": [ { "equiv_sku": "33014-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "33014", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33014-DF" ], "locale_variants": {}, "max_rpm": 5600, "reference_speed_rpm": 3800, "limiting_speed_rpm": 5600 }, { "sku": "33114-DF", "brand": "SKF", "manufacturer_designation": "SKF 33114/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 120, "B_mm": 74, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 361, "static_load_kN": 500, "fatigue_load_limit_kN": 57, "weight_g": 3450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " The rotating cones of 33114-DF take a k5 seat on the 70 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.The SKF 33114/DF is a 70×120×74 mm matched tapered-roller set — two single-row bearings in face-to-face (X) matched pair arrangement, ground and shipped together with the axial clearance fixed at the factory.Digit by digit, 33114-DF reads as the ISO 355 base bearing 33114 supplied as a face-to-face (X) matched pair matched pair (/DF); the 70 mm bore and 120 mm OD are per-bearing, the 74 mm width is for the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 33114-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 70 mm bore. With a pair mass of 3450 g across the 70×120×74 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Cross-section geometry: the 25.0 mm half-section ((120−70)/2) places the roller pitch diameter near 95 mm, and the 74 mm axial width sets the abutment depth — geometry that fixes the contact angle behaviour of 33114-DF. Mounting order matters for 33114-DF: seat the first bearing, fit the ground spacer, then the second bearing, and clamp axially as a unit — the 74 mm catalogue width is the assembled result and the gauge for correct assembly.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "rolling-mill auxiliary drives" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "brinelling from pressing the cone or cup home through the rollers", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "Replace 33114-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 33114-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "O and X arrangements are not interchangeable by turning the set around: 33114-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "The 361/500 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33114/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33114-DF?", "a": "The SKF 33114/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 70 mm bore, 120 mm outer diameter and 74 mm overall width (2.756 × 4.724 × 2.913 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 361 kN, C0 500 kN, fatigue load limit Pu 57 kN, reference speed 3,600 r/min, limiting speed 5,300 r/min, mass about 3.45 kg." }, { "q": "What does the /DF suffix on 33114-DF mean?", "a": "The base 33114 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33114-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 361 kN dynamic and C0 500 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33114 table values." }, { "q": "Can 33114-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 70 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 70 mm bore." } ], "cross_ref": [ { "equiv_sku": "33114", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33114-DF" ], "locale_variants": {}, "max_rpm": 5300, "reference_speed_rpm": 3600, "limiting_speed_rpm": 5300 }, { "sku": "32214-DF", "brand": "SKF", "manufacturer_designation": "SKF 32214/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 125, "B_mm": 66.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 334, "static_load_kN": 415, "fatigue_load_limit_kN": 49, "weight_g": 3300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The SKF 32214/DF is a 70×125×66.5 mm matched tapered-roller set — two single-row bearings in face-to-face (X) matched pair arrangement, ground and shipped together with the axial clearance fixed at the factory.Reading the designation: 32214 is the ISO 355 single-row base bearing (70 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 70×125×66.5 mm; the width covers both bearings of the set. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 66.5 mm overall width of 32214-DF is the axial space the pair occupies. Dividing the pair C 334 kN by the 70 mm bore gives 4.77 kN per millimetre of journal for the complete arrangement — a density metric that compares matched sets across the face-to-face (X) matched pair family. Dimensional interchange map: within its boundary plan the 70×125×66.5 mm envelope of 32214-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Load sharing in 32214-DF depends on spacer face parallelism; a cocked spacer concentrates the reversing thrust on one bearing of the pair and shows up as asymmetric raceway wear at overhaul. A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 70 mm rotating shaft) and square abutments.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "large process pump and compressor shafts" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "Replace 32214-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "Setting is built into 32214-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Clamp the 32214-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "The 334/415 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32214/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32214-DF?", "a": "The SKF 32214/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 70 mm bore, 125 mm outer diameter and 66.5 mm overall width (2.756 × 4.921 × 2.618 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 334 kN, C0 415 kN, fatigue load limit Pu 49 kN, reference speed 3,400 r/min, limiting speed 5,300 r/min, mass about 3.30 kg." }, { "q": "What does the /DF suffix on 32214-DF mean?", "a": "The base 32214 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32214-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 334 kN dynamic and C0 415 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32214 table values." }, { "q": "Can 32214-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 70 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 70 mm bore." } ], "cross_ref": [ { "equiv_sku": "32214", "equiv_brand": "FAG", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32214-DF" ], "locale_variants": {}, "max_rpm": 5300, "reference_speed_rpm": 3400, "limiting_speed_rpm": 5300 }, { "sku": "31314-DF", "brand": "SKF", "manufacturer_designation": "SKF 31314/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 150, "B_mm": 76, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 393, "static_load_kN": 440, "fatigue_load_limit_kN": 54, "weight_g": 6100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Catalogue mass 6100 g covers both bearings and the ground spacer of 31314-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance. Material and manufacturing detail: the 6100 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class. Spacer discipline: the spacer between the two bearings of 31314-DF is ground to the individual set — it carries a serial link to the pair, so never swap spacers between sets of the same designation. A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 70 mm rotating shaft) and square abutments.SKF 31314/DF belongs to the SKF matched tapered-roller range — the 70 mm bore entry in face-to-face (X) matched pair arrangement, dimensioned 150 mm OD and 76 mm overall width for the pair.Reading the designation: 31314 is the ISO 355 single-row base bearing (70 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 70×150×76 mm; the width covers both bearings of the set. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 76 mm overall width of 31314-DF is the axial space the pair occupies.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "marine deck machinery shafts" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "O and X arrangements are not interchangeable by turning the set around: 31314-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "Clamp the 31314-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "O and X arrangements are not interchangeable by turning the set around: 31314-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "The 393/440 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 31314/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 31314-DF?", "a": "The SKF 31314/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 70 mm bore, 150 mm outer diameter and 76 mm overall width (2.756 × 5.906 × 2.992 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 393 kN, C0 440 kN, fatigue load limit Pu 54 kN, reference speed 2,600 r/min, limiting speed 4,500 r/min, mass about 6.10 kg." }, { "q": "What does the /DF suffix on 31314-DF mean?", "a": "The base 31314 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 31314-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 393 kN dynamic and C0 440 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 31314 table values." }, { "q": "Can 31314-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 70 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 70 mm bore." } ], "cross_ref": [ { "equiv_sku": "31314", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "31314-DF" ], "locale_variants": {}, "max_rpm": 4500, "reference_speed_rpm": 2600, "limiting_speed_rpm": 4500 }, { "sku": "33015-DF", "brand": "SKF", "manufacturer_designation": "SKF 33015/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 115, "B_mm": 62, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 286, "static_load_kN": 455, "fatigue_load_limit_kN": 52, "weight_g": 2400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Clamp the assembled pair axially through the cones — never through the rollers — and verify the 62 mm overall width against the catalogue value before final torquing of the shaft nut.For a 75 mm shaft carrying reversing axial load, SKF lists 33015-DF under catalogue execution SKF 33015/DF: a factory-matched face-to-face (X) matched pair tapered-roller pair, set and measured as one unit.Reading the designation: 33015 is the ISO 355 single-row base bearing (75 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 75×115×62 mm; the width covers both bearings of the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 33015-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 75 mm bore. The C0/C balance of the pair is about 1.59; combined with the 52 kN fatigue limit this frames a set sized for reversing combined load on a 75 mm shaft rather than for pure radial duty. Cross-section geometry: the 20.0 mm half-section ((115−75)/2) places the roller pitch diameter near 95 mm, and the 62 mm axial width sets the abutment depth — geometry that fixes the contact angle behaviour of 33015-DF. Inspection shorthand: at overhaul, mark both bearings and the spacer of 33015-DF before disassembly — the set is a matched system, and re-assembling with one component reversed changes the factory setting.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "marine deck machinery shafts" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "Setting is built into 33015-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Setting is built into 33015-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "A matched /DF set is ground as one system: never separate the two bearings of 33015-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "The 286/455 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33015/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33015-DF?", "a": "The SKF 33015/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 75 mm bore, 115 mm outer diameter and 62 mm overall width (2.953 × 4.528 × 2.441 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 286 kN, C0 455 kN, fatigue load limit Pu 52 kN, reference speed 3,600 r/min, limiting speed 5,300 r/min, mass about 2.40 kg." }, { "q": "What does the /DF suffix on 33015-DF mean?", "a": "The base 33015 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33015-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 286 kN dynamic and C0 455 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33015 table values." }, { "q": "Can 33015-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 75 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 75 mm bore." } ], "cross_ref": [ { "equiv_sku": "33015", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33015-DF" ], "locale_variants": {}, "max_rpm": 5300, "reference_speed_rpm": 3600, "limiting_speed_rpm": 5300 }, { "sku": "33015-DFC240", "brand": "SKF", "manufacturer_designation": "SKF 33015/DFC240", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 115, "B_mm": 62, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 286, "static_load_kN": 455, "fatigue_load_limit_kN": 52, "weight_g": 2400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Lubrication for the pair should be sized against the combined 62 mm width and 2400 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.33015-DFC240 (SKF 33015/DFC240) is the face-to-face (X) matched pair matched-set choice for a 75 mm shaft: a pair of tapered roller bearings whose combined envelope is 115×62 mm, delivered ready to mount with controlled internal clearance.Digit by digit, 33015-DFC240 reads as the ISO 355 base bearing 33015 supplied as a face-to-face (X) matched pair matched pair (/DFC240); the 75 mm bore and 115 mm OD are per-bearing, the 62 mm width is for the set. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 62 mm overall width of 33015-DFC240 is the axial space the pair occupies. With a pair mass of 2400 g across the 75×115×62 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Assembly datum check: verify the 62 mm width against the drawing before clamping — the width is the assembled result and the quickest field check that the correct execution of 33015-DFC240 is on the shaft. Mounting order matters for 33015-DFC240: seat the first bearing, fit the ground spacer, then the second bearing, and clamp axially as a unit — the 62 mm catalogue width is the assembled result and the gauge for correct assembly.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "marine deck machinery shafts" ], "failure_modes": [ "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 33015-DFC240 concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Clamp the 33015-DFC240 pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Clamp the 33015-DFC240 pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "The 286/455 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33015/DFC240 designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33015-DFC240?", "a": "The SKF 33015/DFC240 is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 75 mm bore, 115 mm outer diameter and 62 mm overall width (2.953 × 4.528 × 2.441 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 286 kN, C0 455 kN, fatigue load limit Pu 52 kN, reference speed 3,600 r/min, limiting speed 5,300 r/min, mass about 2.40 kg." }, { "q": "What does the /DFC240 suffix on 33015-DFC240 mean?", "a": "The base 33015 is the ISO 355 single-row bearing; the /DFC240 suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33015-DFC240 for one bearing or the pair?", "a": "They are for the complete matched pair: C 286 kN dynamic and C0 455 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33015 table values." }, { "q": "Can 33015-DFC240 be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 75 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 75 mm bore." } ], "cross_ref": [ { "equiv_sku": "33015", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33015-DFC240" ], "locale_variants": {}, "max_rpm": 5300, "reference_speed_rpm": 3600, "limiting_speed_rpm": 5300 }, { "sku": "33115-DF", "brand": "SKF", "manufacturer_designation": "SKF 33115/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 125, "B_mm": 74, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 370, "static_load_kN": 530, "fatigue_load_limit_kN": 60, "weight_g": 3650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33115-DF is a matched pair of single-row tapered roller bearings arranged face-to-face (X) matched pair, supplied by SKF in SKF catalogue PUB BU/P1 17000 as one factory-set unit: the two bearings, spacers and setting are matched together and must not be mixed with other sets.The code breaks down as base bearing 33115 plus matched-set suffix /DF: two bearings of the 75 mm bore size, paired face-to-face (X) matched pair, with the 74 mm overall width spanning the whole arrangement. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 74 mm overall width of 33115-DF is the axial space the pair occupies. With a pair mass of 3650 g across the 75×125×74 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Dimensional interchange map: within its boundary plan the 75×125×74 mm envelope of 33115-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Thermal behaviour of the pair: heat generated in the 75 mm bore cones flows along the shaft and changes the setting; the /DF clearance class is chosen for the catalogue speed range 3,400–5,000 r/min, so re-select the clearance class if the application runs hotter. Clamp the assembled pair axially through the cones — never through the rollers — and verify the 74 mm overall width against the catalogue value before final torquing of the shaft nut.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "paper-machine and printing rolls" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "O and X arrangements are not interchangeable by turning the set around: 33115-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 33115-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 33115-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "The 370/530 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33115/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33115-DF?", "a": "The SKF 33115/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 75 mm bore, 125 mm outer diameter and 74 mm overall width (2.953 × 4.921 × 2.913 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 370 kN, C0 530 kN, fatigue load limit Pu 60 kN, reference speed 3,400 r/min, limiting speed 5,000 r/min, mass about 3.65 kg." }, { "q": "What does the /DF suffix on 33115-DF mean?", "a": "The base 33115 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33115-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 370 kN dynamic and C0 530 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33115 table values." }, { "q": "Can 33115-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 75 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 75 mm bore." } ], "cross_ref": [ { "equiv_sku": "33115", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33115-DF" ], "locale_variants": {}, "max_rpm": 5000, "reference_speed_rpm": 3400, "limiting_speed_rpm": 5000 }, { "sku": "30215-DF", "brand": "SKF", "manufacturer_designation": "SKF 30215/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 130, "B_mm": 54.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 293, "static_load_kN": 355, "fatigue_load_limit_kN": 41.5, "weight_g": 2850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Numbering ties the set to its envelope: base 30215 fixes the 75 mm bore and 130 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 54.5 mm width is the combined pair dimension. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 30215-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 75 mm bore. With a pair mass of 2850 g across the 75×130×54.5 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Dimensional interchange map: within its boundary plan the 75×130×54.5 mm envelope of 30215-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Thermal behaviour of the pair: heat generated in the 75 mm bore cones flows along the shaft and changes the setting; the /DF clearance class is chosen for the catalogue speed range 3,400–5,000 r/min, so re-select the clearance class if the application runs hotter. Do not separate 30215-DF into single-bearing service stock — as individual bearings the components are not interchangeable with catalogue single-row executions because the rings are ground for the set.30215-DF (SKF 30215/DF) is the face-to-face (X) matched pair matched-set choice for a 75 mm shaft: a pair of tapered roller bearings whose combined envelope is 130×54.5 mm, delivered ready to mount with controlled internal clearance.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "crane sheave and hoist gearboxes" ], "failure_modes": [ "roller large-end smearing against the cone rib after EP lubricant film failure", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "Clamp the 30215-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 30215-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 30215-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "The 293/355 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30215/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30215-DF?", "a": "The SKF 30215/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 75 mm bore, 130 mm outer diameter and 54.5 mm overall width (2.953 × 5.118 × 2.146 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 293 kN, C0 355 kN, fatigue load limit Pu 41.5 kN, reference speed 3,400 r/min, limiting speed 5,000 r/min, mass about 2.85 kg." }, { "q": "What does the /DF suffix on 30215-DF mean?", "a": "The base 30215 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 30215-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 293 kN dynamic and C0 355 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30215 table values." }, { "q": "Can 30215-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 75 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 75 mm bore." } ], "cross_ref": [ { "equiv_sku": "30215-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "30215", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30215-DF" ], "locale_variants": {}, "max_rpm": 5000, "reference_speed_rpm": 3400, "limiting_speed_rpm": 5000 }, { "sku": "32215-DF", "brand": "SKF", "manufacturer_designation": "SKF 32215/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 130, "B_mm": 66.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 337, "static_load_kN": 425, "fatigue_load_limit_kN": 49, "weight_g": 3400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "On the SKF nameplate, 32215-DF reads as base 32215 in a /DF matched execution — the suffix is part of the order number because a matched set is ground for a specific axial clearance and cannot be assembled from loose single bearings. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 32215-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 75 mm bore. Catalogue mass 3400 g covers both bearings and the ground spacer of 32215-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance. Operating context for the 75 mm bore: a shaft of this diameter typically runs in the large-bore band of industrial duty, and the 130 mm OD places the housing shoulder near 138 mm outer abutment. Thermal behaviour of the pair: heat generated in the 75 mm bore cones flows along the shaft and changes the setting; the /DF clearance class is chosen for the catalogue speed range 3,200–5,000 r/min, so re-select the clearance class if the application runs hotter. Lubrication for the pair should be sized against the combined 66.5 mm width and 3400 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.32215-DF is a matched pair of single-row tapered roller bearings arranged face-to-face (X) matched pair, supplied by SKF in SKF catalogue PUB BU/P1 17000 as one factory-set unit: the two bearings, spacers and setting are matched together and must not be mixed with other sets.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "paper-machine and printing rolls" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "O and X arrangements are not interchangeable by turning the set around: 32215-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "Clamp the 32215-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Setting is built into 32215-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "The 337/425 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32215/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32215-DF?", "a": "The SKF 32215/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 75 mm bore, 130 mm outer diameter and 66.5 mm overall width (2.953 × 5.118 × 2.618 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 337 kN, C0 425 kN, fatigue load limit Pu 49 kN, reference speed 3,200 r/min, limiting speed 5,000 r/min, mass about 3.40 kg." }, { "q": "What does the /DF suffix on 32215-DF mean?", "a": "The base 32215 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32215-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 337 kN dynamic and C0 425 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32215 table values." }, { "q": "Can 32215-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 75 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 75 mm bore." } ], "cross_ref": [ { "equiv_sku": "32215", "equiv_brand": "FAG", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32215-DF" ], "locale_variants": {}, "max_rpm": 5000, "reference_speed_rpm": 3200, "limiting_speed_rpm": 5000 }, { "sku": "33215-DF", "brand": "SKF", "manufacturer_designation": "SKF 33215/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 130, "B_mm": 82, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 436, "static_load_kN": 600, "fatigue_load_limit_kN": 68, "weight_g": 4500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Reading the designation: 33215 is the ISO 355 single-row base bearing (75 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 75×130×82 mm; the width covers both bearings of the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 33215-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 75 mm bore. With a pair mass of 4500 g across the 75×130×82 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Load system: C 436 kN against C0 600 kN gives a 1.38 balance, and 5.81 kN of dynamic capacity per millimetre of the 75 mm bore is the density figure to compare against neighbouring sizes. Setting note for 33215-DF: the axial clearance is set at the factory by selective spacer grinding for the /DF execution; in service, re-checking end play after the first thermal cycle catches seating relaxation before it becomes roller skid. The rotating cones of 33215-DF take a k5 seat on the 75 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.For a 75 mm shaft carrying reversing axial load, SKF lists 33215-DF under catalogue execution SKF 33215/DF: a factory-matched face-to-face (X) matched pair tapered-roller pair, set and measured as one unit.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "crane sheave and hoist gearboxes" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "Replace 33215-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "Clamp the 33215-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 33215-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "The 436/600 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33215/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33215-DF?", "a": "The SKF 33215/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 75 mm bore, 130 mm outer diameter and 82 mm overall width (2.953 × 5.118 × 3.228 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 436 kN, C0 600 kN, fatigue load limit Pu 68 kN, reference speed 3,200 r/min, limiting speed 4,800 r/min, mass about 4.50 kg." }, { "q": "What does the /DF suffix on 33215-DF mean?", "a": "The base 33215 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33215-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 436 kN dynamic and C0 600 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33215 table values." }, { "q": "Can 33215-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 75 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 75 mm bore." } ], "cross_ref": [ { "equiv_sku": "33215", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33215-DF" ], "locale_variants": {}, "max_rpm": 4800, "reference_speed_rpm": 3200, "limiting_speed_rpm": 4800 }, { "sku": "31315-DF", "brand": "SKF", "manufacturer_designation": "SKF 31315/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 160, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 438, "static_load_kN": 490, "fatigue_load_limit_kN": 58.5, "weight_g": 7150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 80 mm overall width of 31315-DF is the axial space the pair occupies. Selection arithmetic: the catalogue C 438 kN and C0 490 kN are ratings of the complete pair, not of one bearing — never halve them back to a single-row figure when checking L10 life, and use the pair Pu 58.5 kN as the fatigue floor. Assembly datum check: verify the 80 mm width against the drawing before clamping — the width is the assembled result and the quickest field check that the correct execution of 31315-DF is on the shaft. When a matched /DF set like 31315-DF is replaced, replace the whole set: mixing a new bearing with a worn partner from the old set leaves the clearance and load sharing of the pair undefined. Do not separate 31315-DF into single-bearing service stock — as individual bearings the components are not interchangeable with catalogue single-row executions because the rings are ground for the set.31315-DF is a matched pair of single-row tapered roller bearings arranged face-to-face (X) matched pair, supplied by SKF in SKF catalogue PUB BU/P1 17000 as one factory-set unit: the two bearings, spacers and setting are matched together and must not be mixed with other sets.Reading the designation: 31315 is the ISO 355 single-row base bearing (75 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 75×160×80 mm; the width covers both bearings of the set.", "applications": [ "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "rolling-mill auxiliary drives" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "Setting is built into 31315-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 31315-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "O and X arrangements are not interchangeable by turning the set around: 31315-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "The 438/490 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 31315/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 31315-DF?", "a": "The SKF 31315/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 75 mm bore, 160 mm outer diameter and 80 mm overall width (2.953 × 6.299 × 3.15 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 438 kN, C0 490 kN, fatigue load limit Pu 58.5 kN, reference speed 2,400 r/min, limiting speed 4,300 r/min, mass about 7.15 kg." }, { "q": "What does the /DF suffix on 31315-DF mean?", "a": "The base 31315 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 31315-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 438 kN dynamic and C0 490 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 31315 table values." }, { "q": "Can 31315-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 75 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 75 mm bore." } ], "cross_ref": [ { "equiv_sku": "31315", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "31315-DF" ], "locale_variants": {}, "max_rpm": 4300, "reference_speed_rpm": 2400, "limiting_speed_rpm": 4300 }, { "sku": "32315-DF", "brand": "SKF", "manufacturer_designation": "SKF 32315/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 160, "B_mm": 116, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 713, "static_load_kN": 880, "fatigue_load_limit_kN": 102, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 116 mm overall width of 32315-DF is the axial space the pair occupies. Dividing the pair C 713 kN by the 75 mm bore gives 9.51 kN per millimetre of journal for the complete arrangement — a density metric that compares matched sets across the face-to-face (X) matched pair family. Operating context for the 75 mm bore: a shaft of this diameter typically runs in the large-bore band of industrial duty, and the 160 mm OD places the housing shoulder near 168 mm outer abutment. Setting note for 32315-DF: the axial clearance is set at the factory by selective spacer grinding for the /DF execution; in service, re-checking end play after the first thermal cycle catches seating relaxation before it becomes roller skid. Clamp the assembled pair axially through the cones — never through the rollers — and verify the 116 mm overall width against the catalogue value before final torquing of the shaft nut.For a 75 mm shaft carrying reversing axial load, SKF lists 32315-DF under catalogue execution SKF 32315/DF: a factory-matched face-to-face (X) matched pair tapered-roller pair, set and measured as one unit.Numbering ties the set to its envelope: base 32315 fixes the 75 mm bore and 160 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 116 mm width is the combined pair dimension.", "applications": [ "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "rolling-mill auxiliary drives" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Clamp the 32315-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Setting is built into 32315-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Setting is built into 32315-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "The 713/880 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32315/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32315-DF?", "a": "The SKF 32315/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 75 mm bore, 160 mm outer diameter and 116 mm overall width (2.953 × 6.299 × 4.567 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 713 kN, C0 880 kN, fatigue load limit Pu 102 kN, reference speed 2,600 r/min, limiting speed 4,300 r/min, mass about 11.00 kg." }, { "q": "What does the /DF suffix on 32315-DF mean?", "a": "The base 32315 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32315-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 713 kN dynamic and C0 880 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32315 table values." }, { "q": "Can 32315-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 75 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 75 mm bore." } ], "cross_ref": [ { "equiv_sku": "32315", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32315-DF" ], "locale_variants": {}, "max_rpm": 4300, "reference_speed_rpm": 2600, "limiting_speed_rpm": 4300 }, { "sku": "32016X-DF", "brand": "SKF", "manufacturer_designation": "SKF 32016 X/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 125, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 288, "static_load_kN": 430, "fatigue_load_limit_kN": 49, "weight_g": 2650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Digit by digit, 32016X-DF reads as the ISO 355 base bearing 32016 X supplied as a face-to-face (X) matched pair matched pair (/DF); the 80 mm bore and 125 mm OD are per-bearing, the 58 mm width is for the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 32016X-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 80 mm bore. The C0/C balance of the pair is about 1.49; combined with the 49 kN fatigue limit this frames a set sized for reversing combined load on a 80 mm shaft rather than for pure radial duty. Dimensional interchange map: within its boundary plan the 80×125×58 mm envelope of 32016X-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Thermal behaviour of the pair: heat generated in the 80 mm bore cones flows along the shaft and changes the setting; the /DF clearance class is chosen for the catalogue speed range 3,200–5,000 r/min, so re-select the clearance class if the application runs hotter. Lubrication for the pair should be sized against the combined 58 mm width and 2650 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.SKF 32016 X/DF belongs to the SKF matched tapered-roller range — the 80 mm bore entry in face-to-face (X) matched pair arrangement, dimensioned 125 mm OD and 58 mm overall width for the pair.", "applications": [ "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "uneven load sharing in a pair when spacer faces are not parallel to the bore", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "A matched /DF set is ground as one system: never separate the two bearings of 32016X-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32016X-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "A matched /DF set is ground as one system: never separate the two bearings of 32016X-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "The 288/430 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32016 X/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32016X-DF?", "a": "The SKF 32016 X/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 80 mm bore, 125 mm outer diameter and 58 mm overall width (3.15 × 4.921 × 2.283 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 288 kN, C0 430 kN, fatigue load limit Pu 49 kN, reference speed 3,200 r/min, limiting speed 5,000 r/min, mass about 2.65 kg." }, { "q": "What does the /DF suffix on 32016X-DF mean?", "a": "The base 32016 X is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32016X-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 288 kN dynamic and C0 430 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32016 X table values." }, { "q": "Can 32016X-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 80 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 80 mm bore." } ], "cross_ref": [ { "equiv_sku": "32016X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32016X-DF" ], "locale_variants": {}, "max_rpm": 5000, "reference_speed_rpm": 3200, "limiting_speed_rpm": 5000 }, { "sku": "33116-DF", "brand": "SKF", "manufacturer_designation": "SKF 33116/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 130, "B_mm": 74, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 379, "static_load_kN": 560, "fatigue_load_limit_kN": 62, "weight_g": 3800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Lubrication for the pair should be sized against the combined 74 mm width and 3800 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.Ordering number SKF 33116/DF in SKF catalogue PUB BU/P1 17000 denotes two single-row tapered roller bearings supplied as a matched face-to-face (X) matched pair set for a 80 mm shaft — one order number, one factory setting.The code breaks down as base bearing 33116 plus matched-set suffix /DF: two bearings of the 80 mm bore size, paired face-to-face (X) matched pair, with the 74 mm overall width spanning the whole arrangement. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 74 mm overall width of 33116-DF is the axial space the pair occupies. The C0/C balance of the pair is about 1.48; combined with the 62 kN fatigue limit this frames a set sized for reversing combined load on a 80 mm shaft rather than for pure radial duty. Material and manufacturing detail: the 3800 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class. Spacer discipline: the spacer between the two bearings of 33116-DF is ground to the individual set — it carries a serial link to the pair, so never swap spacers between sets of the same designation.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Setting is built into 33116-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Setting is built into 33116-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 33116-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "The 379/560 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33116/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33116-DF?", "a": "The SKF 33116/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 80 mm bore, 130 mm outer diameter and 74 mm overall width (3.15 × 5.118 × 2.913 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 379 kN, C0 560 kN, fatigue load limit Pu 62 kN, reference speed 3,200 r/min, limiting speed 4,800 r/min, mass about 3.80 kg." }, { "q": "What does the /DF suffix on 33116-DF mean?", "a": "The base 33116 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33116-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 379 kN dynamic and C0 560 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33116 table values." }, { "q": "Can 33116-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 80 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 80 mm bore." } ], "cross_ref": [ { "equiv_sku": "33116", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33116-DF" ], "locale_variants": {}, "max_rpm": 4800, "reference_speed_rpm": 3200, "limiting_speed_rpm": 4800 }, { "sku": "32216-DF", "brand": "SKF", "manufacturer_designation": "SKF 32216/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 140, "B_mm": 70.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 391, "static_load_kN": 490, "fatigue_load_limit_kN": 57, "weight_g": 4250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Ordering number SKF 32216/DF in SKF catalogue PUB BU/P1 17000 denotes two single-row tapered roller bearings supplied as a matched face-to-face (X) matched pair set for a 80 mm shaft — one order number, one factory setting.Digit by digit, 32216-DF reads as the ISO 355 base bearing 32216 supplied as a face-to-face (X) matched pair matched pair (/DF); the 80 mm bore and 140 mm OD are per-bearing, the 70.5 mm width is for the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 32216-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 80 mm bore. Catalogue mass 4250 g covers both bearings and the ground spacer of 32216-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance. Assembly datum check: verify the 70.5 mm width against the drawing before clamping — the width is the assembled result and the quickest field check that the correct execution of 32216-DF is on the shaft. Spacer discipline: the spacer between the two bearings of 32216-DF is ground to the individual set — it carries a serial link to the pair, so never swap spacers between sets of the same designation. Do not separate 32216-DF into single-bearing service stock — as individual bearings the components are not interchangeable with catalogue single-row executions because the rings are ground for the set.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "marine deck machinery shafts" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "hard-particle indentation of the tapered raceway in unfiltered oil", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "A matched /DF set is ground as one system: never separate the two bearings of 32216-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32216-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Setting is built into 32216-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "The 391/490 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32216/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32216-DF?", "a": "The SKF 32216/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 80 mm bore, 140 mm outer diameter and 70.5 mm overall width (3.15 × 5.512 × 2.776 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 391 kN, C0 490 kN, fatigue load limit Pu 57 kN, reference speed 3,000 r/min, limiting speed 4,500 r/min, mass about 4.25 kg." }, { "q": "What does the /DF suffix on 32216-DF mean?", "a": "The base 32216 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32216-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 391 kN dynamic and C0 490 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32216 table values." }, { "q": "Can 32216-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 80 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 80 mm bore." } ], "cross_ref": [ { "equiv_sku": "32216", "equiv_brand": "FAG", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32216-DF" ], "locale_variants": {}, "max_rpm": 4500, "reference_speed_rpm": 3000, "limiting_speed_rpm": 4500 }, { "sku": "33216-DF", "brand": "SKF", "manufacturer_designation": "SKF 33216/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 140, "B_mm": 92, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 527, "static_load_kN": 750, "fatigue_load_limit_kN": 83, "weight_g": 5950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "SKF 33216/DF belongs to the SKF matched tapered-roller range — the 80 mm bore entry in face-to-face (X) matched pair arrangement, dimensioned 140 mm OD and 92 mm overall width for the pair.Reading the designation: 33216 is the ISO 355 single-row base bearing (80 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 80×140×92 mm; the width covers both bearings of the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 33216-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 80 mm bore. Dividing the pair C 527 kN by the 80 mm bore gives 6.59 kN per millimetre of journal for the complete arrangement — a density metric that compares matched sets across the face-to-face (X) matched pair family. Assembly datum check: verify the 92 mm width against the drawing before clamping — the width is the assembled result and the quickest field check that the correct execution of 33216-DF is on the shaft. When a matched /DF set like 33216-DF is replaced, replace the whole set: mixing a new bearing with a worn partner from the old set leaves the clearance and load sharing of the pair undefined. A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 80 mm rotating shaft) and square abutments.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "brinelling from pressing the cone or cup home through the rollers", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "Clamp the 33216-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Setting is built into 33216-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "A matched /DF set is ground as one system: never separate the two bearings of 33216-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "The 527/750 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33216/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33216-DF?", "a": "The SKF 33216/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 80 mm bore, 140 mm outer diameter and 92 mm overall width (3.15 × 5.512 × 3.622 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 527 kN, C0 750 kN, fatigue load limit Pu 83 kN, reference speed 3,000 r/min, limiting speed 4,500 r/min, mass about 5.95 kg." }, { "q": "What does the /DF suffix on 33216-DF mean?", "a": "The base 33216 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33216-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 527 kN dynamic and C0 750 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33216 table values." }, { "q": "Can 33216-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 80 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 80 mm bore." } ], "cross_ref": [ { "equiv_sku": "33216", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33216-DF" ], "locale_variants": {}, "max_rpm": 4500, "reference_speed_rpm": 3000, "limiting_speed_rpm": 4500 }, { "sku": "31316-DF", "brand": "SKF", "manufacturer_designation": "SKF 31316/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 170, "B_mm": 85, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 473, "static_load_kN": 530, "fatigue_load_limit_kN": 61, "weight_g": 8650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Reading the designation: 31316 is the ISO 355 single-row base bearing (80 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 80×170×85 mm; the width covers both bearings of the set. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 85 mm overall width of 31316-DF is the axial space the pair occupies. With a pair mass of 8650 g across the 80×170×85 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Dimensional interchange map: within its boundary plan the 80×170×85 mm envelope of 31316-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Spacer discipline: the spacer between the two bearings of 31316-DF is ground to the individual set — it carries a serial link to the pair, so never swap spacers between sets of the same designation. Clamp the assembled pair axially through the cones — never through the rollers — and verify the 85 mm overall width against the catalogue value before final torquing of the shaft nut.Ordering number SKF 31316/DF in SKF catalogue PUB BU/P1 17000 denotes two single-row tapered roller bearings supplied as a matched face-to-face (X) matched pair set for a 80 mm shaft — one order number, one factory setting.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "marine deck machinery shafts" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "A matched /DF set is ground as one system: never separate the two bearings of 31316-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "Clamp the 31316-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Clamp the 31316-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "The 473/530 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 31316/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 31316-DF?", "a": "The SKF 31316/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 80 mm bore, 170 mm outer diameter and 85 mm overall width (3.15 × 6.693 × 3.346 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 473 kN, C0 530 kN, fatigue load limit Pu 61 kN, reference speed 2,400 r/min, limiting speed 4,000 r/min, mass about 8.65 kg." }, { "q": "What does the /DF suffix on 31316-DF mean?", "a": "The base 31316 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 31316-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 473 kN dynamic and C0 530 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 31316 table values." }, { "q": "Can 31316-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 80 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 80 mm bore." } ], "cross_ref": [ { "equiv_sku": "31316", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "31316-DF" ], "locale_variants": {}, "max_rpm": 4000, "reference_speed_rpm": 2400, "limiting_speed_rpm": 4000 }, { "sku": "32316-DF", "brand": "SKF", "manufacturer_designation": "SKF 32316/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 170, "B_mm": 123, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 693, "static_load_kN": 1000, "fatigue_load_limit_kN": 112, "weight_g": 13000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Numbering ties the set to its envelope: base 32316 fixes the 80 mm bore and 170 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 123 mm width is the combined pair dimension. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 123 mm overall width of 32316-DF is the axial space the pair occupies. Catalogue mass 13000 g covers both bearings and the ground spacer of 32316-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance. Cross-section geometry: the 45.0 mm half-section ((170−80)/2) places the roller pitch diameter near 125 mm, and the 123 mm axial width sets the abutment depth — geometry that fixes the contact angle behaviour of 32316-DF. Mounting order matters for 32316-DF: seat the first bearing, fit the ground spacer, then the second bearing, and clamp axially as a unit — the 123 mm catalogue width is the assembled result and the gauge for correct assembly. Lubrication for the pair should be sized against the combined 123 mm width and 13000 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.SKF 32316/DF belongs to the SKF matched tapered-roller range — the 80 mm bore entry in face-to-face (X) matched pair arrangement, dimensioned 170 mm OD and 123 mm overall width for the pair.", "applications": [ "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives", "construction machinery drives" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "edge loading from shaft deflection or housing misalignment", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "O and X arrangements are not interchangeable by turning the set around: 32316-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "Clamp the 32316-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Setting is built into 32316-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "The 693/1000 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32316/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32316-DF?", "a": "The SKF 32316/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 80 mm bore, 170 mm outer diameter and 123 mm overall width (3.15 × 6.693 × 4.843 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 693 kN, C0 1000 kN, fatigue load limit Pu 112 kN, reference speed 2,600 r/min, limiting speed 4,000 r/min, mass about 13.00 kg." }, { "q": "What does the /DF suffix on 32316-DF mean?", "a": "The base 32316 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32316-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 693 kN dynamic and C0 1000 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32316 table values." }, { "q": "Can 32316-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 80 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 80 mm bore." } ], "cross_ref": [ { "equiv_sku": "32316", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32316-DF" ], "locale_variants": {}, "max_rpm": 4000, "reference_speed_rpm": 2600, "limiting_speed_rpm": 4000 }, { "sku": "32017X-DF", "brand": "SKF", "manufacturer_designation": "SKF 32017 X/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 130, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 293, "static_load_kN": 450, "fatigue_load_limit_kN": 51, "weight_g": 2800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 58 mm overall width of 32017X-DF is the axial space the pair occupies. Catalogue mass 2800 g covers both bearings and the ground spacer of 32017X-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance. Journal and housing interface: the 85 mm bore takes a k5 shaft seat and the 130 mm outside diameter pairs with an H7 housing bore; the 58 mm width defines shoulder depth and the 2800 g mass is the dead load in thermal-growth calculations. When a matched /DF set like 32017X-DF is replaced, replace the whole set: mixing a new bearing with a worn partner from the old set leaves the clearance and load sharing of the pair undefined. Do not separate 32017X-DF into single-bearing service stock — as individual bearings the components are not interchangeable with catalogue single-row executions because the rings are ground for the set.SKF 32017 X/DF belongs to the SKF matched tapered-roller range — the 85 mm bore entry in face-to-face (X) matched pair arrangement, dimensioned 130 mm OD and 58 mm overall width for the pair.On the SKF nameplate, 32017X-DF reads as base 32017 X in a /DF matched execution — the suffix is part of the order number because a matched set is ground for a specific axial clearance and cannot be assembled from loose single bearings.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "construction machinery drives" ], "failure_modes": [ "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "grease degradation after long shelf storage without rotation or re-greasing" ], "pitfalls": [ "O and X arrangements are not interchangeable by turning the set around: 32017X-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "Setting is built into 32017X-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "O and X arrangements are not interchangeable by turning the set around: 32017X-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "The 293/450 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32017 X/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32017X-DF?", "a": "The SKF 32017 X/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 85 mm bore, 130 mm outer diameter and 58 mm overall width (3.346 × 5.118 × 2.283 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 293 kN, C0 450 kN, fatigue load limit Pu 51 kN, reference speed 3,200 r/min, limiting speed 4,800 r/min, mass about 2.80 kg." }, { "q": "What does the /DF suffix on 32017X-DF mean?", "a": "The base 32017 X is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32017X-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 293 kN dynamic and C0 450 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32017 X table values." }, { "q": "Can 32017X-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 85 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 85 mm bore." } ], "cross_ref": [ { "equiv_sku": "32017X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32017X-DF" ], "locale_variants": {}, "max_rpm": 4800, "reference_speed_rpm": 3200, "limiting_speed_rpm": 4800 }, { "sku": "33017-DF", "brand": "SKF", "manufacturer_designation": "SKF 33017/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 130, "B_mm": 72, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 382, "static_load_kN": 620, "fatigue_load_limit_kN": 69.5, "weight_g": 3500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Material and manufacturing detail: the 3500 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class. Thermal behaviour of the pair: heat generated in the 85 mm bore cones flows along the shaft and changes the setting; the /DF clearance class is chosen for the catalogue speed range 3,200–4,800 r/min, so re-select the clearance class if the application runs hotter. The rotating cones of 33017-DF take a k5 seat on the 85 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.33017-DF is a matched pair of single-row tapered roller bearings arranged face-to-face (X) matched pair, supplied by SKF in SKF catalogue PUB BU/P1 17000 as one factory-set unit: the two bearings, spacers and setting are matched together and must not be mixed with other sets.Reading the designation: 33017 is the ISO 355 single-row base bearing (85 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 85×130×72 mm; the width covers both bearings of the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 33017-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 85 mm bore. Catalogue mass 3500 g covers both bearings and the ground spacer of 33017-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "construction machinery drives" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 33017-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 33017-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "A matched /DF set is ground as one system: never separate the two bearings of 33017-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "The 382/620 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33017/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33017-DF?", "a": "The SKF 33017/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 85 mm bore, 130 mm outer diameter and 72 mm overall width (3.346 × 5.118 × 2.835 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 382 kN, C0 620 kN, fatigue load limit Pu 69.5 kN, reference speed 3,200 r/min, limiting speed 4,800 r/min, mass about 3.50 kg." }, { "q": "What does the /DF suffix on 33017-DF mean?", "a": "The base 33017 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33017-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 382 kN dynamic and C0 620 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33017 table values." }, { "q": "Can 33017-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 85 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 85 mm bore." } ], "cross_ref": [ { "equiv_sku": "33017", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33017-DF" ], "locale_variants": {}, "max_rpm": 4800, "reference_speed_rpm": 3200, "limiting_speed_rpm": 4800 }, { "sku": "30217-DF", "brand": "SKF", "manufacturer_designation": "SKF 30217/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 150, "B_mm": 61, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 370, "static_load_kN": 440, "fatigue_load_limit_kN": 51, "weight_g": 4250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Reading the designation: 30217 is the ISO 355 single-row base bearing (85 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 85×150×61 mm; the width covers both bearings of the set. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 61 mm overall width of 30217-DF is the axial space the pair occupies. Dividing the pair C 370 kN by the 85 mm bore gives 4.35 kN per millimetre of journal for the complete arrangement — a density metric that compares matched sets across the face-to-face (X) matched pair family. Cross-section geometry: the 32.5 mm half-section ((150−85)/2) places the roller pitch diameter near 117 mm, and the 61 mm axial width sets the abutment depth — geometry that fixes the contact angle behaviour of 30217-DF. When a matched /DF set like 30217-DF is replaced, replace the whole set: mixing a new bearing with a worn partner from the old set leaves the clearance and load sharing of the pair undefined. A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 85 mm rotating shaft) and square abutments.The SKF 30217/DF is a 85×150×61 mm matched tapered-roller set — two single-row bearings in face-to-face (X) matched pair arrangement, ground and shipped together with the axial clearance fixed at the factory.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "rolling-mill auxiliary drives" ], "failure_modes": [ "uneven load sharing in a pair when spacer faces are not parallel to the bore", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "A matched /DF set is ground as one system: never separate the two bearings of 30217-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "Clamp the 30217-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Clamp the 30217-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "The 370/440 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30217/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30217-DF?", "a": "The SKF 30217/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 85 mm bore, 150 mm outer diameter and 61 mm overall width (3.346 × 5.906 × 2.402 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 370 kN, C0 440 kN, fatigue load limit Pu 51 kN, reference speed 3,000 r/min, limiting speed 4,300 r/min, mass about 4.25 kg." }, { "q": "What does the /DF suffix on 30217-DF mean?", "a": "The base 30217 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 30217-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 370 kN dynamic and C0 440 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30217 table values." }, { "q": "Can 30217-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 85 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 85 mm bore." } ], "cross_ref": [ { "equiv_sku": "30217", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30217-DF" ], "locale_variants": {}, "max_rpm": 4300, "reference_speed_rpm": 3000, "limiting_speed_rpm": 4300 }, { "sku": "32217-DF", "brand": "SKF", "manufacturer_designation": "SKF 32217/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 150, "B_mm": 77, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 451, "static_load_kN": 570, "fatigue_load_limit_kN": 65.5, "weight_g": 5400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The code breaks down as base bearing 32217 plus matched-set suffix /DF: two bearings of the 85 mm bore size, paired face-to-face (X) matched pair, with the 77 mm overall width spanning the whole arrangement. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 77 mm overall width of 32217-DF is the axial space the pair occupies. Catalogue mass 5400 g covers both bearings and the ground spacer of 32217-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance. Journal and housing interface: the 85 mm bore takes a k5 shaft seat and the 150 mm outside diameter pairs with an H7 housing bore; the 77 mm width defines shoulder depth and the 5400 g mass is the dead load in thermal-growth calculations. Mounting order matters for 32217-DF: seat the first bearing, fit the ground spacer, then the second bearing, and clamp axially as a unit — the 77 mm catalogue width is the assembled result and the gauge for correct assembly. The rotating cones of 32217-DF take a k5 seat on the 85 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.SKF 32217/DF belongs to the SKF matched tapered-roller range — the 85 mm bore entry in face-to-face (X) matched pair arrangement, dimensioned 150 mm OD and 77 mm overall width for the pair.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "large process pump and compressor shafts" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "Replace 32217-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32217-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Replace 32217-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 451/570 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32217/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32217-DF?", "a": "The SKF 32217/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 85 mm bore, 150 mm outer diameter and 77 mm overall width (3.346 × 5.906 × 3.031 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 451 kN, C0 570 kN, fatigue load limit Pu 65.5 kN, reference speed 2,800 r/min, limiting speed 4,300 r/min, mass about 5.40 kg." }, { "q": "What does the /DF suffix on 32217-DF mean?", "a": "The base 32217 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32217-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 451 kN dynamic and C0 570 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32217 table values." }, { "q": "Can 32217-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 85 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 85 mm bore." } ], "cross_ref": [ { "equiv_sku": "32217", "equiv_brand": "FAG", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32217-DF" ], "locale_variants": {}, "max_rpm": 4300, "reference_speed_rpm": 2800, "limiting_speed_rpm": 4300 }, { "sku": "33217-DF", "brand": "SKF", "manufacturer_designation": "SKF 33217/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 150, "B_mm": 98, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 606, "static_load_kN": 850, "fatigue_load_limit_kN": 96.5, "weight_g": 7300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Lubrication for the pair should be sized against the combined 98 mm width and 7300 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.33217-DF is a matched pair of single-row tapered roller bearings arranged face-to-face (X) matched pair, supplied by SKF in SKF catalogue PUB BU/P1 17000 as one factory-set unit: the two bearings, spacers and setting are matched together and must not be mixed with other sets.On the SKF nameplate, 33217-DF reads as base 33217 in a /DF matched execution — the suffix is part of the order number because a matched set is ground for a specific axial clearance and cannot be assembled from loose single bearings. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 33217-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 85 mm bore. Dividing the pair C 606 kN by the 85 mm bore gives 7.13 kN per millimetre of journal for the complete arrangement — a density metric that compares matched sets across the face-to-face (X) matched pair family. Cross-section geometry: the 32.5 mm half-section ((150−85)/2) places the roller pitch diameter near 117 mm, and the 98 mm axial width sets the abutment depth — geometry that fixes the contact angle behaviour of 33217-DF. Setting note for 33217-DF: the axial clearance is set at the factory by selective spacer grinding for the /DF execution; in service, re-checking end play after the first thermal cycle catches seating relaxation before it becomes roller skid.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "rolling-mill auxiliary drives" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "edge loading from shaft deflection or housing misalignment", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Setting is built into 33217-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Clamp the 33217-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "A matched /DF set is ground as one system: never separate the two bearings of 33217-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "The 606/850 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33217/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33217-DF?", "a": "The SKF 33217/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 85 mm bore, 150 mm outer diameter and 98 mm overall width (3.346 × 5.906 × 3.858 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 606 kN, C0 850 kN, fatigue load limit Pu 96.5 kN, reference speed 2,800 r/min, limiting speed 4,300 r/min, mass about 7.30 kg." }, { "q": "What does the /DF suffix on 33217-DF mean?", "a": "The base 33217 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33217-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 606 kN dynamic and C0 850 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33217 table values." }, { "q": "Can 33217-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 85 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 85 mm bore." } ], "cross_ref": [ { "equiv_sku": "33217", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33217-DF" ], "locale_variants": {}, "max_rpm": 4300, "reference_speed_rpm": 2800, "limiting_speed_rpm": 4300 }, { "sku": "31317-DF", "brand": "SKF", "manufacturer_designation": "SKF 31317/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 180, "B_mm": 89, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 510, "static_load_kN": 570, "fatigue_load_limit_kN": 64, "weight_g": 9900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 31317-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 85 mm bore. With a pair mass of 9900 g across the 85×180×89 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Material and manufacturing detail: the 9900 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class. Mounting order matters for 31317-DF: seat the first bearing, fit the ground spacer, then the second bearing, and clamp axially as a unit — the 89 mm catalogue width is the assembled result and the gauge for correct assembly. A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 85 mm rotating shaft) and square abutments.SKF 31317/DF belongs to the SKF matched tapered-roller range — the 85 mm bore entry in face-to-face (X) matched pair arrangement, dimensioned 180 mm OD and 89 mm overall width for the pair.On the SKF nameplate, 31317-DF reads as base 31317 in a /DF matched execution — the suffix is part of the order number because a matched set is ground for a specific axial clearance and cannot be assembled from loose single bearings.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "large process pump and compressor shafts" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "mounting score marks when the cone is cocked over the shaft keyway or a burr", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Replace 31317-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "Clamp the 31317-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "A matched /DF set is ground as one system: never separate the two bearings of 31317-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "The 510/570 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 31317/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 31317-DF?", "a": "The SKF 31317/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 85 mm bore, 180 mm outer diameter and 89 mm overall width (3.346 × 7.087 × 3.504 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 510 kN, C0 570 kN, fatigue load limit Pu 64 kN, reference speed 2,200 r/min, limiting speed 3,800 r/min, mass about 9.90 kg." }, { "q": "What does the /DF suffix on 31317-DF mean?", "a": "The base 31317 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 31317-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 510 kN dynamic and C0 570 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 31317 table values." }, { "q": "Can 31317-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 85 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 85 mm bore." } ], "cross_ref": [ { "equiv_sku": "31317", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "31317-DF" ], "locale_variants": {}, "max_rpm": 3800, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3800 }, { "sku": "32018X-DF", "brand": "SKF", "manufacturer_designation": "SKF 32018 X/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 140, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 356, "static_load_kN": 540, "fatigue_load_limit_kN": 62, "weight_g": 3650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Speed planning for the set uses the catalogue pair values: 3,000 r/min thermal reference and 4,300 r/min mechanical limiting speed — a matched pair runs warmer than one bearing because two roller sets share the 64 mm space. Dimensional interchange map: within its boundary plan the 90×140×64 mm envelope of 32018X-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Setting note for 32018X-DF: the axial clearance is set at the factory by selective spacer grinding for the /DF execution; in service, re-checking end play after the first thermal cycle catches seating relaxation before it becomes roller skid. A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 90 mm rotating shaft) and square abutments.32018X-DF (SKF 32018 X/DF) is the face-to-face (X) matched pair matched-set choice for a 90 mm shaft: a pair of tapered roller bearings whose combined envelope is 140×64 mm, delivered ready to mount with controlled internal clearance.Reading the designation: 32018 X is the ISO 355 single-row base bearing (90 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 90×140×64 mm; the width covers both bearings of the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 32018X-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 90 mm bore.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "crane sheave and hoist gearboxes" ], "failure_modes": [ "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "Replace 32018X-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "Clamp the 32018X-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Clamp the 32018X-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "The 356/540 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32018 X/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32018X-DF?", "a": "The SKF 32018 X/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 90 mm bore, 140 mm outer diameter and 64 mm overall width (3.543 × 5.512 × 2.52 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 356 kN, C0 540 kN, fatigue load limit Pu 62 kN, reference speed 3,000 r/min, limiting speed 4,300 r/min, mass about 3.65 kg." }, { "q": "What does the /DF suffix on 32018X-DF mean?", "a": "The base 32018 X is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32018X-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 356 kN dynamic and C0 540 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32018 X table values." }, { "q": "Can 32018X-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 90 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 90 mm bore." } ], "cross_ref": [ { "equiv_sku": "32018X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32018X-DF" ], "locale_variants": {}, "max_rpm": 4300, "reference_speed_rpm": 3000, "limiting_speed_rpm": 4300 }, { "sku": "33018-DF", "brand": "SKF", "manufacturer_designation": "SKF 33018/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 140, "B_mm": 78, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 457, "static_load_kN": 710, "fatigue_load_limit_kN": 78, "weight_g": 4500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Spacer discipline: the spacer between the two bearings of 33018-DF is ground to the individual set — it carries a serial link to the pair, so never swap spacers between sets of the same designation. The rotating cones of 33018-DF take a k5 seat on the 90 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.For a 90 mm shaft carrying reversing axial load, SKF lists 33018-DF under catalogue execution SKF 33018/DF: a factory-matched face-to-face (X) matched pair tapered-roller pair, set and measured as one unit.Digit by digit, 33018-DF reads as the ISO 355 base bearing 33018 supplied as a face-to-face (X) matched pair matched pair (/DF); the 90 mm bore and 140 mm OD are per-bearing, the 78 mm width is for the set. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 78 mm overall width of 33018-DF is the axial space the pair occupies. Catalogue mass 4500 g covers both bearings and the ground spacer of 33018-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance. Assembly datum check: verify the 78 mm width against the drawing before clamping — the width is the assembled result and the quickest field check that the correct execution of 33018-DF is on the shaft.", "applications": [ "paper-machine and printing rolls", "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "O and X arrangements are not interchangeable by turning the set around: 33018-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "Setting is built into 33018-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Replace 33018-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 457/710 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33018/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33018-DF?", "a": "The SKF 33018/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 90 mm bore, 140 mm outer diameter and 78 mm overall width (3.543 × 5.512 × 3.071 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 457 kN, C0 710 kN, fatigue load limit Pu 78 kN, reference speed 3,000 r/min, limiting speed 4,500 r/min, mass about 4.50 kg." }, { "q": "What does the /DF suffix on 33018-DF mean?", "a": "The base 33018 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33018-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 457 kN dynamic and C0 710 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33018 table values." }, { "q": "Can 33018-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 90 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 90 mm bore." } ], "cross_ref": [ { "equiv_sku": "33018", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33018-DF" ], "locale_variants": {}, "max_rpm": 4500, "reference_speed_rpm": 3000, "limiting_speed_rpm": 4500 }, { "sku": "30218-DF", "brand": "SKF", "manufacturer_designation": "SKF 30218/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 160, "B_mm": 65, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 411, "static_load_kN": 490, "fatigue_load_limit_kN": 57, "weight_g": 5200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30218-DF (SKF 30218/DF) is the face-to-face (X) matched pair matched-set choice for a 90 mm shaft: a pair of tapered roller bearings whose combined envelope is 160×65 mm, delivered ready to mount with controlled internal clearance.Reading the designation: 30218 is the ISO 355 single-row base bearing (90 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 90×160×65 mm; the width covers both bearings of the set. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 65 mm overall width of 30218-DF is the axial space the pair occupies. Catalogue mass 5200 g covers both bearings and the ground spacer of 30218-DF; keep the set complete — substituting one bearing or a non-ground spacer destroys the factory clearance. Dimensional interchange map: within its boundary plan the 90×160×65 mm envelope of 30218-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Setting note for 30218-DF: the axial clearance is set at the factory by selective spacer grinding for the /DF execution; in service, re-checking end play after the first thermal cycle catches seating relaxation before it becomes roller skid. Do not separate 30218-DF into single-bearing service stock — as individual bearings the components are not interchangeable with catalogue single-row executions because the rings are ground for the set.", "applications": [ "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "construction machinery drives" ], "failure_modes": [ "uneven load sharing in a pair when spacer faces are not parallel to the bore", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rib-roller contact scoring from loss of the EP additive film", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 30218-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 30218-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Clamp the 30218-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "The 411/490 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30218/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30218-DF?", "a": "The SKF 30218/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 90 mm bore, 160 mm outer diameter and 65 mm overall width (3.543 × 6.299 × 2.559 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 411 kN, C0 490 kN, fatigue load limit Pu 57 kN, reference speed 2,800 r/min, limiting speed 4,000 r/min, mass about 5.20 kg." }, { "q": "What does the /DF suffix on 30218-DF mean?", "a": "The base 30218 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 30218-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 411 kN dynamic and C0 490 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30218 table values." }, { "q": "Can 30218-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 90 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 90 mm bore." } ], "cross_ref": [ { "equiv_sku": "30218", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30218-DF" ], "locale_variants": {}, "max_rpm": 4000, "reference_speed_rpm": 2800, "limiting_speed_rpm": 4000 }, { "sku": "32218-DF", "brand": "SKF", "manufacturer_designation": "SKF 32218/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 160, "B_mm": 85, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 529, "static_load_kN": 680, "fatigue_load_limit_kN": 76.5, "weight_g": 6850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32218-DF is a matched pair of single-row tapered roller bearings arranged face-to-face (X) matched pair, supplied by SKF in SKF catalogue PUB BU/P1 17000 as one factory-set unit: the two bearings, spacers and setting are matched together and must not be mixed with other sets.The code breaks down as base bearing 32218 plus matched-set suffix /DF: two bearings of the 90 mm bore size, paired face-to-face (X) matched pair, with the 85 mm overall width spanning the whole arrangement. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 85 mm overall width of 32218-DF is the axial space the pair occupies. Speed planning for the set uses the catalogue pair values: 2,600 r/min thermal reference and 4,000 r/min mechanical limiting speed — a matched pair runs warmer than one bearing because two roller sets share the 85 mm space. Material and manufacturing detail: the 6850 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class. Setting note for 32218-DF: the axial clearance is set at the factory by selective spacer grinding for the /DF execution; in service, re-checking end play after the first thermal cycle catches seating relaxation before it becomes roller skid. A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 90 mm rotating shaft) and square abutments.", "applications": [ "construction machinery drives", "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "construction machinery drives" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Clamp the 32218-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Clamp the 32218-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32218-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "The 529/680 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32218/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32218-DF?", "a": "The SKF 32218/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 90 mm bore, 160 mm outer diameter and 85 mm overall width (3.543 × 6.299 × 3.346 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 529 kN, C0 680 kN, fatigue load limit Pu 76.5 kN, reference speed 2,600 r/min, limiting speed 4,000 r/min, mass about 6.85 kg." }, { "q": "What does the /DF suffix on 32218-DF mean?", "a": "The base 32218 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32218-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 529 kN dynamic and C0 680 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32218 table values." }, { "q": "Can 32218-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 90 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 90 mm bore." } ], "cross_ref": [ { "equiv_sku": "32218", "equiv_brand": "FAG", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32218-DF" ], "locale_variants": {}, "max_rpm": 4000, "reference_speed_rpm": 2600, "limiting_speed_rpm": 4000 }, { "sku": "31318-DF", "brand": "SKF", "manufacturer_designation": "SKF 31318/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 190, "B_mm": 93, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 486, "static_load_kN": 630, "fatigue_load_limit_kN": 71, "weight_g": 11500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "On the SKF nameplate, 31318-DF reads as base 31318 in a /DF matched execution — the suffix is part of the order number because a matched set is ground for a specific axial clearance and cannot be assembled from loose single bearings. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 31318-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 90 mm bore. The C0/C balance of the pair is about 1.30; combined with the 71 kN fatigue limit this frames a set sized for reversing combined load on a 90 mm shaft rather than for pure radial duty. Assembly datum check: verify the 93 mm width against the drawing before clamping — the width is the assembled result and the quickest field check that the correct execution of 31318-DF is on the shaft. Inspection shorthand: at overhaul, mark both bearings and the spacer of 31318-DF before disassembly — the set is a matched system, and re-assembling with one component reversed changes the factory setting. Do not separate 31318-DF into single-bearing service stock — as individual bearings the components are not interchangeable with catalogue single-row executions because the rings are ground for the set.31318-DF is a matched pair of single-row tapered roller bearings arranged face-to-face (X) matched pair, supplied by SKF in SKF catalogue PUB BU/P1 17000 as one factory-set unit: the two bearings, spacers and setting are matched together and must not be mixed with other sets.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "paper-machine and printing rolls" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "Clamp the 31318-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 31318-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "A matched /DF set is ground as one system: never separate the two bearings of 31318-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "The 486/630 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 31318/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 31318-DF?", "a": "The SKF 31318/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 90 mm bore, 190 mm outer diameter and 93 mm overall width (3.543 × 7.48 × 3.661 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 486 kN, C0 630 kN, fatigue load limit Pu 71 kN, reference speed 1,900 r/min, limiting speed 3,400 r/min, mass about 11.50 kg." }, { "q": "What does the /DF suffix on 31318-DF mean?", "a": "The base 31318 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 31318-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 486 kN dynamic and C0 630 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 31318 table values." }, { "q": "Can 31318-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 90 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 90 mm bore." } ], "cross_ref": [ { "equiv_sku": "31318", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "31318-DF" ], "locale_variants": {}, "max_rpm": 3400, "reference_speed_rpm": 1900, "limiting_speed_rpm": 3400 }, { "sku": "32318-DF", "brand": "SKF", "manufacturer_designation": "SKF 32318/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 190, "B_mm": 135, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 835, "static_load_kN": 1220, "fatigue_load_limit_kN": 132, "weight_g": 17500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "Reading the designation: 32318 is the ISO 355 single-row base bearing (90 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 90×190×135 mm; the width covers both bearings of the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 32318-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 90 mm bore. Speed planning for the set uses the catalogue pair values: 2,200 r/min thermal reference and 3,600 r/min mechanical limiting speed — a matched pair runs warmer than one bearing because two roller sets share the 135 mm space. Operating context for the 90 mm bore: a shaft of this diameter typically runs in the large-bore band of industrial duty, and the 190 mm OD places the housing shoulder near 198 mm outer abutment. Load sharing in 32318-DF depends on spacer face parallelism; a cocked spacer concentrates the reversing thrust on one bearing of the pair and shows up as asymmetric raceway wear at overhaul. Clamp the assembled pair axially through the cones — never through the rollers — and verify the 135 mm overall width against the catalogue value before final torquing of the shaft nut.For a 90 mm shaft carrying reversing axial load, SKF lists 32318-DF under catalogue execution SKF 32318/DF: a factory-matched face-to-face (X) matched pair tapered-roller pair, set and measured as one unit.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "paper-machine and printing rolls" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "hard-particle indentation of the tapered raceway in unfiltered oil", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32318-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Setting is built into 32318-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32318-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "The 835/1220 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32318/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32318-DF?", "a": "The SKF 32318/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 90 mm bore, 190 mm outer diameter and 135 mm overall width (3.543 × 7.48 × 5.315 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 835 kN, C0 1220 kN, fatigue load limit Pu 132 kN, reference speed 2,200 r/min, limiting speed 3,600 r/min, mass about 17.50 kg." }, { "q": "What does the /DF suffix on 32318-DF mean?", "a": "The base 32318 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32318-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 835 kN dynamic and C0 1220 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32318 table values." }, { "q": "Can 32318-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 90 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 90 mm bore." } ], "cross_ref": [ { "equiv_sku": "32318", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32318-DF" ], "locale_variants": {}, "max_rpm": 3600, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3600 }, { "sku": "32019X-DF", "brand": "SKF", "manufacturer_designation": "SKF 32019 X/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 95, "D_mm": 145, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 353, "static_load_kN": 540, "fatigue_load_limit_kN": 61, "weight_g": 3800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Journal and housing interface: the 95 mm bore takes a k5 shaft seat and the 145 mm outside diameter pairs with an H7 housing bore; the 64 mm width defines shoulder depth and the 3800 g mass is the dead load in thermal-growth calculations. Inspection shorthand: at overhaul, mark both bearings and the spacer of 32019X-DF before disassembly — the set is a matched system, and re-assembling with one component reversed changes the factory setting. Lubrication for the pair should be sized against the combined 64 mm width and 3800 g mass: two roller sets sweep twice the contact area of a single bearing of the same bore.32019X-DF (SKF 32019 X/DF) is the face-to-face (X) matched pair matched-set choice for a 95 mm shaft: a pair of tapered roller bearings whose combined envelope is 145×64 mm, delivered ready to mount with controlled internal clearance.Numbering ties the set to its envelope: base 32019 X fixes the 95 mm bore and 145 mm OD of each bearing, the /DF suffix fixes the arrangement and setting, and the catalogue 64 mm width is the combined pair dimension. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 64 mm overall width of 32019X-DF is the axial space the pair occupies. The C0/C balance of the pair is about 1.53; combined with the 61 kN fatigue limit this frames a set sized for reversing combined load on a 95 mm shaft rather than for pure radial duty.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "large process pump and compressor shafts" ], "failure_modes": [ "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "A matched /DF set is ground as one system: never separate the two bearings of 32019X-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32019X-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32019X-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "The 353/540 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32019 X/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32019X-DF?", "a": "The SKF 32019 X/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 95 mm bore, 145 mm outer diameter and 64 mm overall width (3.74 × 5.709 × 2.52 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 353 kN, C0 540 kN, fatigue load limit Pu 61 kN, reference speed 2,800 r/min, limiting speed 4,300 r/min, mass about 3.80 kg." }, { "q": "What does the /DF suffix on 32019X-DF mean?", "a": "The base 32019 X is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32019X-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 353 kN dynamic and C0 540 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32019 X table values." }, { "q": "Can 32019X-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 95 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 95 mm bore." } ], "cross_ref": [ { "equiv_sku": "32019X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32019X-DF" ], "locale_variants": {}, "max_rpm": 4300, "reference_speed_rpm": 2800, "limiting_speed_rpm": 4300 }, { "sku": "33019-DF", "brand": "SKF", "manufacturer_designation": "SKF 33019/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 95, "D_mm": 145, "B_mm": 78, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 467, "static_load_kN": 735, "fatigue_load_limit_kN": 81.5, "weight_g": 4700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Journal and housing interface: the 95 mm bore takes a k5 shaft seat and the 145 mm outside diameter pairs with an H7 housing bore; the 78 mm width defines shoulder depth and the 4700 g mass is the dead load in thermal-growth calculations. When a matched /DF set like 33019-DF is replaced, replace the whole set: mixing a new bearing with a worn partner from the old set leaves the clearance and load sharing of the pair undefined. A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 95 mm rotating shaft) and square abutments.SKF 33019/DF belongs to the SKF matched tapered-roller range — the 95 mm bore entry in face-to-face (X) matched pair arrangement, dimensioned 145 mm OD and 78 mm overall width for the pair.Digit by digit, 33019-DF reads as the ISO 355 base bearing 33019 supplied as a face-to-face (X) matched pair matched pair (/DF); the 95 mm bore and 145 mm OD are per-bearing, the 78 mm width is for the set. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 78 mm overall width of 33019-DF is the axial space the pair occupies. Selection arithmetic: the catalogue C 467 kN and C0 735 kN are ratings of the complete pair, not of one bearing — never halve them back to a single-row figure when checking L10 life, and use the pair Pu 81.5 kN as the fatigue floor.", "applications": [ "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "crane sheave and hoist gearboxes" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "roller large-end smearing against the cone rib after EP lubricant film failure", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "grease degradation after long shelf storage without rotation or re-greasing", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "Setting is built into 33019-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Clamp the 33019-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Replace 33019-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 467/735 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 33019/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 33019-DF?", "a": "The SKF 33019/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 95 mm bore, 145 mm outer diameter and 78 mm overall width (3.74 × 5.709 × 3.071 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 467 kN, C0 735 kN, fatigue load limit Pu 81.5 kN, reference speed 2,800 r/min, limiting speed 4,300 r/min, mass about 4.70 kg." }, { "q": "What does the /DF suffix on 33019-DF mean?", "a": "The base 33019 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 33019-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 467 kN dynamic and C0 735 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 33019 table values." }, { "q": "Can 33019-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 95 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 95 mm bore." } ], "cross_ref": [ { "equiv_sku": "33019", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "33019-DF" ], "locale_variants": {}, "max_rpm": 4300, "reference_speed_rpm": 2800, "limiting_speed_rpm": 4300 }, { "sku": "32219-DF", "brand": "SKF", "manufacturer_designation": "SKF 32219/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 95, "D_mm": 170, "B_mm": 91, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 597, "static_load_kN": 780, "fatigue_load_limit_kN": 86.5, "weight_g": 8400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Do not separate 32219-DF into single-bearing service stock — as individual bearings the components are not interchangeable with catalogue single-row executions because the rings are ground for the set.Ordering number SKF 32219/DF in SKF catalogue PUB BU/P1 17000 denotes two single-row tapered roller bearings supplied as a matched face-to-face (X) matched pair set for a 95 mm shaft — one order number, one factory setting.The code breaks down as base bearing 32219 plus matched-set suffix /DF: two bearings of the 95 mm bore size, paired face-to-face (X) matched pair, with the 91 mm overall width spanning the whole arrangement. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 91 mm overall width of 32219-DF is the axial space the pair occupies. With a pair mass of 8400 g across the 95×170×91 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Assembly datum check: verify the 91 mm width against the drawing before clamping — the width is the assembled result and the quickest field check that the correct execution of 32219-DF is on the shaft. Mounting order matters for 32219-DF: seat the first bearing, fit the ground spacer, then the second bearing, and clamp axially as a unit — the 91 mm catalogue width is the assembled result and the gauge for correct assembly.", "applications": [ "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives", "large process pump and compressor shafts" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "roller large-end smearing against the cone rib after EP lubricant film failure", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "O and X arrangements are not interchangeable by turning the set around: 32219-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32219-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32219-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "The 597/780 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32219/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32219-DF?", "a": "The SKF 32219/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 95 mm bore, 170 mm outer diameter and 91 mm overall width (3.74 × 6.693 × 3.583 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 597 kN, C0 780 kN, fatigue load limit Pu 86.5 kN, reference speed 2,600 r/min, limiting speed 3,800 r/min, mass about 8.40 kg." }, { "q": "What does the /DF suffix on 32219-DF mean?", "a": "The base 32219 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32219-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 597 kN dynamic and C0 780 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32219 table values." }, { "q": "Can 32219-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 95 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 95 mm bore." } ], "cross_ref": [ { "equiv_sku": "32219", "equiv_brand": "FAG", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32219-DF" ], "locale_variants": {}, "max_rpm": 3800, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3800 }, { "sku": "31319-DF", "brand": "SKF", "manufacturer_designation": "SKF 31319/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 95, "D_mm": 200, "B_mm": 99, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 539, "static_load_kN": 710, "fatigue_load_limit_kN": 78, "weight_g": 13500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 99 mm overall width of 31319-DF is the axial space the pair occupies. Dividing the pair C 539 kN by the 95 mm bore gives 5.67 kN per millimetre of journal for the complete arrangement — a density metric that compares matched sets across the face-to-face (X) matched pair family. Dimensional interchange map: within its boundary plan the 95×200×99 mm envelope of 31319-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Load sharing in 31319-DF depends on spacer face parallelism; a cocked spacer concentrates the reversing thrust on one bearing of the pair and shows up as asymmetric raceway wear at overhaul. The rotating cones of 31319-DF take a k5 seat on the 95 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.For a 95 mm shaft carrying reversing axial load, SKF lists 31319-DF under catalogue execution SKF 31319/DF: a factory-matched face-to-face (X) matched pair tapered-roller pair, set and measured as one unit.Digit by digit, 31319-DF reads as the ISO 355 base bearing 31319 supplied as a face-to-face (X) matched pair matched pair (/DF); the 95 mm bore and 200 mm OD are per-bearing, the 99 mm width is for the set.", "applications": [ "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "hard-particle indentation of the tapered raceway in unfiltered oil" ], "pitfalls": [ "Setting is built into 31319-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Setting is built into 31319-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Replace 31319-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 539/710 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 31319/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 31319-DF?", "a": "The SKF 31319/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 95 mm bore, 200 mm outer diameter and 99 mm overall width (3.74 × 7.874 × 3.898 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 539 kN, C0 710 kN, fatigue load limit Pu 78 kN, reference speed 1,800 r/min, limiting speed 3,400 r/min, mass about 13.50 kg." }, { "q": "What does the /DF suffix on 31319-DF mean?", "a": "The base 31319 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 31319-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 539 kN dynamic and C0 710 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 31319 table values." }, { "q": "Can 31319-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 95 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 95 mm bore." } ], "cross_ref": [ { "equiv_sku": "31319", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "31319-DF" ], "locale_variants": {}, "max_rpm": 3400, "reference_speed_rpm": 1800, "limiting_speed_rpm": 3400 }, { "sku": "32920-DF", "brand": "SKF", "manufacturer_designation": "SKF 32920/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 140, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 252, "static_load_kN": 405, "fatigue_load_limit_kN": 45, "weight_g": 2350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Load system: C 252 kN against C0 405 kN gives a 1.61 balance, and 2.52 kN of dynamic capacity per millimetre of the 100 mm bore is the density figure to compare against neighbouring sizes. Setting note for 32920-DF: the axial clearance is set at the factory by selective spacer grinding for the /DF execution; in service, re-checking end play after the first thermal cycle catches seating relaxation before it becomes roller skid. The rotating cones of 32920-DF take a k5 seat on the 100 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.The SKF 32920/DF is a 100×140×50 mm matched tapered-roller set — two single-row bearings in face-to-face (X) matched pair arrangement, ground and shipped together with the axial clearance fixed at the factory.On the SKF nameplate, 32920-DF reads as base 32920 in a /DF matched execution — the suffix is part of the order number because a matched set is ground for a specific axial clearance and cannot be assembled from loose single bearings. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 50 mm overall width of 32920-DF is the axial space the pair occupies. Speed planning for the set uses the catalogue pair values: 2,800 r/min thermal reference and 4,300 r/min mechanical limiting speed — a matched pair runs warmer than one bearing because two roller sets share the 50 mm space.", "applications": [ "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes", "rolling-mill auxiliary drives" ], "failure_modes": [ "roller large-end smearing against the cone rib after EP lubricant film failure", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rib-roller contact scoring from loss of the EP additive film", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Replace 32920-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 32920-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Setting is built into 32920-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "The 252/405 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32920/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32920-DF?", "a": "The SKF 32920/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 100 mm bore, 140 mm outer diameter and 50 mm overall width (3.937 × 5.512 × 1.969 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 252 kN, C0 405 kN, fatigue load limit Pu 45 kN, reference speed 2,800 r/min, limiting speed 4,300 r/min, mass about 2.35 kg." }, { "q": "What does the /DF suffix on 32920-DF mean?", "a": "The base 32920 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32920-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 252 kN dynamic and C0 405 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32920 table values." }, { "q": "Can 32920-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 100 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 100 mm bore." } ], "cross_ref": [ { "equiv_sku": "32920-NTN", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32920", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32920-DF" ], "locale_variants": {}, "max_rpm": 4300, "reference_speed_rpm": 2800, "limiting_speed_rpm": 4300 }, { "sku": "32020X-DF", "brand": "SKF", "manufacturer_designation": "SKF 32020 X/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 150, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 359, "static_load_kN": 560, "fatigue_load_limit_kN": 62, "weight_g": 3900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 32020X-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 100 mm bore. The C0/C balance of the pair is about 1.56; combined with the 62 kN fatigue limit this frames a set sized for reversing combined load on a 100 mm shaft rather than for pure radial duty. Load system: C 359 kN against C0 560 kN gives a 1.56 balance, and 3.59 kN of dynamic capacity per millimetre of the 100 mm bore is the density figure to compare against neighbouring sizes. Inspection shorthand: at overhaul, mark both bearings and the spacer of 32020X-DF before disassembly — the set is a matched system, and re-assembling with one component reversed changes the factory setting. A matched /DF set needs no setting adjustment at mounting: the clearance is built in; the assembler's job is clean seats, correct fits (k5 on a 100 mm rotating shaft) and square abutments.In SKF catalogue PUB BU/P1 17000, 32020X-DF appears as SKF 32020 X/DF: a matched face-to-face (X) matched pair pair for a 100 mm shaft, rated as a set at C 359 kN and C0 560 kN.The code breaks down as base bearing 32020 X plus matched-set suffix /DF: two bearings of the 100 mm bore size, paired face-to-face (X) matched pair, with the 64 mm overall width spanning the whole arrangement.", "applications": [ "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives", "heavy industrial gearboxes and speed reducers" ], "failure_modes": [ "false brinelling on idle paired sets exposed to machine vibration", "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "fretting corrosion on a loose rotating shaft seat", "edge loading from shaft deflection or housing misalignment" ], "pitfalls": [ "Setting is built into 32020X-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Setting is built into 32020X-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Setting is built into 32020X-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "The 359/560 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32020 X/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32020X-DF?", "a": "The SKF 32020 X/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 100 mm bore, 150 mm outer diameter and 64 mm overall width (3.937 × 5.906 × 2.52 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 359 kN, C0 560 kN, fatigue load limit Pu 62 kN, reference speed 2,600 r/min, limiting speed 4,000 r/min, mass about 3.90 kg." }, { "q": "What does the /DF suffix on 32020X-DF mean?", "a": "The base 32020 X is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32020X-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 359 kN dynamic and C0 560 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32020 X table values." }, { "q": "Can 32020X-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 100 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 100 mm bore." } ], "cross_ref": [ { "equiv_sku": "32020X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32020X-DF" ], "locale_variants": {}, "max_rpm": 4000, "reference_speed_rpm": 2600, "limiting_speed_rpm": 4000 }, { "sku": "30220-DF", "brand": "SKF", "manufacturer_designation": "SKF 30220/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 180, "B_mm": 74, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 521, "static_load_kN": 640, "fatigue_load_limit_kN": 72, "weight_g": 7500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Dimensional interchange map: within its boundary plan the 100×180×74 mm envelope of 30220-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Mounting order matters for 30220-DF: seat the first bearing, fit the ground spacer, then the second bearing, and clamp axially as a unit — the 74 mm catalogue width is the assembled result and the gauge for correct assembly. The rotating cones of 30220-DF take a k5 seat on the 100 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.30220-DF (SKF 30220/DF) is the face-to-face (X) matched pair matched-set choice for a 100 mm shaft: a pair of tapered roller bearings whose combined envelope is 180×74 mm, delivered ready to mount with controlled internal clearance.Reading the designation: 30220 is the ISO 355 single-row base bearing (100 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 100×180×74 mm; the width covers both bearings of the set. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 30220-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 100 mm bore. Speed planning for the set uses the catalogue pair values: 2,400 r/min thermal reference and 3,600 r/min mechanical limiting speed — a matched pair runs warmer than one bearing because two roller sets share the 74 mm space.", "applications": [ "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives", "paper-machine and printing rolls" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "grease degradation after long shelf storage without rotation or re-greasing", "brinelling from pressing the cone or cup home through the rollers" ], "pitfalls": [ "O and X arrangements are not interchangeable by turning the set around: 30220-DF in face-to-face (X) matched pair arrangement has its load-line geometry fixed — specify the arrangement from the shaft thermal and stiffness analysis.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 30220-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Setting is built into 30220-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "The 521/640 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30220/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30220-DF?", "a": "The SKF 30220/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 100 mm bore, 180 mm outer diameter and 74 mm overall width (3.937 × 7.087 × 2.913 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 521 kN, C0 640 kN, fatigue load limit Pu 72 kN, reference speed 2,400 r/min, limiting speed 3,600 r/min, mass about 7.50 kg." }, { "q": "What does the /DF suffix on 30220-DF mean?", "a": "The base 30220 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 30220-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 521 kN dynamic and C0 640 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30220 table values." }, { "q": "Can 30220-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 100 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 100 mm bore." } ], "cross_ref": [ { "equiv_sku": "30220", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30220-DF" ], "locale_variants": {}, "max_rpm": 3600, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3600 }, { "sku": "32220-DF", "brand": "SKF", "manufacturer_designation": "SKF 32220/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 180, "B_mm": 98, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 668, "static_load_kN": 880, "fatigue_load_limit_kN": 96.5, "weight_g": 10000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Dimensional interchange map: within its boundary plan the 100×180×98 mm envelope of 32220-DF is fixed, so shoulder, spacer and seal drawings can be dimensioned straight from the catalogue table. Inspection shorthand: at overhaul, mark both bearings and the spacer of 32220-DF before disassembly — the set is a matched system, and re-assembling with one component reversed changes the factory setting. Clamp the assembled pair axially through the cones — never through the rollers — and verify the 98 mm overall width against the catalogue value before final torquing of the shaft nut.32220-DF (SKF 32220/DF) is the face-to-face (X) matched pair matched-set choice for a 100 mm shaft: a pair of tapered roller bearings whose combined envelope is 180×98 mm, delivered ready to mount with controlled internal clearance.The code breaks down as base bearing 32220 plus matched-set suffix /DF: two bearings of the 100 mm bore size, paired face-to-face (X) matched pair, with the 98 mm overall width spanning the whole arrangement. Face-to-face matching puts the small rib ends outward, so the pressure cones cross inside the pair; 32220-DF therefore runs cooler where the shaft expands axially, at the price of lower moment stiffness than an O-arrangement of the same 100 mm bore. The C0/C balance of the pair is about 1.32; combined with the 96.5 kN fatigue limit this frames a set sized for reversing combined load on a 100 mm shaft rather than for pure radial duty.", "applications": [ "crane sheave and hoist gearboxes", "paper-machine and printing rolls", "construction machinery drives", "paper-machine and printing rolls" ], "failure_modes": [ "uneven load sharing in a pair when spacer faces are not parallel to the bore", "false brinelling on idle paired sets exposed to machine vibration", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "A matched /DF set is ground as one system: never separate the two bearings of 32220-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "Clamp the 32220-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Replace 32220-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "The 668/880 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32220/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32220-DF?", "a": "The SKF 32220/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 100 mm bore, 180 mm outer diameter and 98 mm overall width (3.937 × 7.087 × 3.858 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 668 kN, C0 880 kN, fatigue load limit Pu 96.5 kN, reference speed 2,400 r/min, limiting speed 3,600 r/min, mass about 10.00 kg." }, { "q": "What does the /DF suffix on 32220-DF mean?", "a": "The base 32220 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32220-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 668 kN dynamic and C0 880 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32220 table values." }, { "q": "Can 32220-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 100 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 100 mm bore." } ], "cross_ref": [ { "equiv_sku": "32220", "equiv_brand": "FAG", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32220-DF" ], "locale_variants": {}, "max_rpm": 3600, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3600 }, { "sku": "30320-DF", "brand": "SKF", "manufacturer_designation": "SKF 30320/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 215, "B_mm": 103, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 739, "static_load_kN": 980, "fatigue_load_limit_kN": 106, "weight_g": 17000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Mounting order matters for 30320-DF: seat the first bearing, fit the ground spacer, then the second bearing, and clamp axially as a unit — the 103 mm catalogue width is the assembled result and the gauge for correct assembly. The rotating cones of 30320-DF take a k5 seat on the 100 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.For a 100 mm shaft carrying reversing axial load, SKF lists 30320-DF under catalogue execution SKF 30320/DF: a factory-matched face-to-face (X) matched pair tapered-roller pair, set and measured as one unit.The code breaks down as base bearing 30320 plus matched-set suffix /DF: two bearings of the 100 mm bore size, paired face-to-face (X) matched pair, with the 103 mm overall width spanning the whole arrangement. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 103 mm overall width of 30320-DF is the axial space the pair occupies. Speed planning for the set uses the catalogue pair values: 1,900 r/min thermal reference and 3,200 r/min mechanical limiting speed — a matched pair runs warmer than one bearing because two roller sets share the 103 mm space. Operating context for the 100 mm bore: a shaft of this diameter typically runs in the large-bore band of industrial duty, and the 215 mm OD places the housing shoulder near 223 mm outer abutment.", "applications": [ "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives", "crane sheave and hoist gearboxes" ], "failure_modes": [ "preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways", "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr", "fretting corrosion on a loose rotating shaft seat" ], "pitfalls": [ "Clamp the 30320-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 30320-DF concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.", "Setting is built into 30320-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "The 739/980 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 30320/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 30320-DF?", "a": "The SKF 30320/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 100 mm bore, 215 mm outer diameter and 103 mm overall width (3.937 × 8.465 × 4.055 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 739 kN, C0 980 kN, fatigue load limit Pu 106 kN, reference speed 1,900 r/min, limiting speed 3,200 r/min, mass about 17.00 kg." }, { "q": "What does the /DF suffix on 30320-DF mean?", "a": "The base 30320 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 30320-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 739 kN dynamic and C0 980 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30320 table values." }, { "q": "Can 30320-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 100 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 100 mm bore." } ], "cross_ref": [ { "equiv_sku": "30320", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "30320-DF" ], "locale_variants": {}, "max_rpm": 3200, "reference_speed_rpm": 1900, "limiting_speed_rpm": 3200 }, { "sku": "31320X-DF", "brand": "SKF", "manufacturer_designation": "SKF 31320 X/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 215, "B_mm": 113, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 685, "static_load_kN": 930, "fatigue_load_limit_kN": 102, "weight_g": 18500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Clamp the assembled pair axially through the cones — never through the rollers — and verify the 113 mm overall width against the catalogue value before final torquing of the shaft nut.31320X-DF (SKF 31320 X/DF) is the face-to-face (X) matched pair matched-set choice for a 100 mm shaft: a pair of tapered roller bearings whose combined envelope is 215×113 mm, delivered ready to mount with controlled internal clearance.Reading the designation: 31320 X is the ISO 355 single-row base bearing (100 mm bore), and the suffix /DF marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 100×215×113 mm; the width covers both bearings of the set. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 113 mm overall width of 31320X-DF is the axial space the pair occupies. With a pair mass of 18500 g across the 100×215×113 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Journal and housing interface: the 100 mm bore takes a k5 shaft seat and the 215 mm outside diameter pairs with an H7 housing bore; the 113 mm width defines shoulder depth and the 18500 g mass is the dead load in thermal-growth calculations. Spacer discipline: the spacer between the two bearings of 31320X-DF is ground to the individual set — it carries a serial link to the pair, so never swap spacers between sets of the same designation.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "paper-machine and printing rolls" ], "failure_modes": [ "thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting", "uneven load sharing in a pair when spacer faces are not parallel to the bore", "pressed-steel cage wear or fracture after prolonged running above the limiting speed", "electrical pitting on VFD-driven shafts without grounding protection", "rib-roller contact scoring from loss of the EP additive film" ], "pitfalls": [ "Replace 31320X-DF as a complete set: pairing a new bearing with a worn partner leaves the clearance undefined even when the designation matches.", "Clamp the 31320X-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "A matched /DF set is ground as one system: never separate the two bearings of 31320X-DF or swap the spacer — the factory clearance is lost the moment the set is broken.", "The 685/930 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 31320 X/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 31320X-DF?", "a": "The SKF 31320 X/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 100 mm bore, 215 mm outer diameter and 113 mm overall width (3.937 × 8.465 × 4.449 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 685 kN, C0 930 kN, fatigue load limit Pu 102 kN, reference speed 1,700 r/min, limiting speed 3,000 r/min, mass about 18.50 kg." }, { "q": "What does the /DF suffix on 31320X-DF mean?", "a": "The base 31320 X is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 31320X-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 685 kN dynamic and C0 930 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 31320 X table values." }, { "q": "Can 31320X-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 100 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 100 mm bore." } ], "cross_ref": [ { "equiv_sku": "31320X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "31320X-DF" ], "locale_variants": {}, "max_rpm": 3000, "reference_speed_rpm": 1700, "limiting_speed_rpm": 3000 }, { "sku": "32320-DF", "brand": "SKF", "manufacturer_designation": "SKF 32320/DF", "series": "matched-df-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 215, "B_mm": 155, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 1057, "static_load_kN": 1560, "fatigue_load_limit_kN": 166, "weight_g": 26000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": " Thermal behaviour of the pair: heat generated in the 100 mm bore cones flows along the shaft and changes the setting; the /DF clearance class is chosen for the catalogue speed range 1,900–3,200 r/min, so re-select the clearance class if the application runs hotter. Clamp the assembled pair axially through the cones — never through the rollers — and verify the 155 mm overall width against the catalogue value before final torquing of the shaft nut.For a 100 mm shaft carrying reversing axial load, SKF lists 32320-DF under catalogue execution SKF 32320/DF: a factory-matched face-to-face (X) matched pair tapered-roller pair, set and measured as one unit.On the SKF nameplate, 32320-DF reads as base 32320 in a /DF matched execution — the suffix is part of the order number because a matched set is ground for a specific axial clearance and cannot be assembled from loose single bearings. In the face-to-face (X) arrangement the load lines of the two bearings converge toward the shaft axis: the set tolerates shaft deflection and thermal growth better than a back-to-back pair, but is less stiff against overturning moments. The 155 mm overall width of 32320-DF is the axial space the pair occupies. With a pair mass of 26000 g across the 100×215×155 mm envelope, the set replaces what would otherwise be two separate bearings plus spacer grinding work — the factory setting is the engineering value being purchased. Material and manufacturing detail: the 26000 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class.", "applications": [ "marine deck machinery shafts", "heavy industrial gearboxes and speed reducers", "large process pump and compressor shafts", "rolling-mill auxiliary drives" ], "failure_modes": [ "axial overload spalling at the roller-rib contact beyond the single-row thrust rating", "false brinelling on idle paired sets exposed to machine vibration", "cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity", "mounting score marks when the cone is cocked over the shaft keyway or a burr", "mounting score marks when the cone is cocked over the shaft keyway or a burr" ], "pitfalls": [ "Setting is built into 32320-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Setting is built into 32320-DF; the classic field error is re-adjusting a matched pair as if it were two loose single bearings, which destroys the /DF clearance class.", "Clamp the 32320-DF pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.", "The 1057/1560 kN ratings are SKF catalogue 17000 values for this execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.", "Quote the full SKF 32320/DF designation when purchasing — base-number-only orders are ambiguous across executions and variants." ], "faq": [ { "q": "What are the dimensions and catalogue data of 32320-DF?", "a": "The SKF 32320/DF is a matched pair of single-row tapered roller bearings in face-to-face (X) matched pair arrangement with 100 mm bore, 215 mm outer diameter and 155 mm overall width (3.937 × 8.465 × 6.102 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 1057 kN, C0 1560 kN, fatigue load limit Pu 166 kN, reference speed 1,900 r/min, limiting speed 3,200 r/min, mass about 26.00 kg." }, { "q": "What does the /DF suffix on 32320-DF mean?", "a": "The base 32320 is the ISO 355 single-row bearing; the /DF suffix marks the matched-set execution — the arrangement (face-to-face (X)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering." }, { "q": "Are the C and C0 ratings of 32320-DF for one bearing or the pair?", "a": "They are for the complete matched pair: C 1057 kN dynamic and C0 1560 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 32320 table values." }, { "q": "Can 32320-DF be adjusted like two loose tapered bearings?", "a": "No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 100 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class." }, { "q": "When should a face-to-face (X) matched set be chosen?", "a": "Choose the face-to-face (X) set where the shaft grows thermally or alignment is imperfect — the converging load lines tolerate deflection. It is the default choice for wheel hubs and general gearbox shafts at the 100 mm bore." } ], "cross_ref": [ { "equiv_sku": "32320", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://cdn.skfmediahub.skf.com/api/public/0901d196802809de/pdf_preview_medium/0901d196802809de_pdf_preview_medium.pdf", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants", "extracted_at": "2026-09-29", "last_verified": "2026-09-29", "confidence_score": 0.7, "status": "published", "aliases": [ "32320-DF" ], "locale_variants": {}, "max_rpm": 3200, "reference_speed_rpm": 1900, "limiting_speed_rpm": 3200 } ]